src/services/utilities.ts (2,525 lines of code) (raw):
/* @internal */ // Don't expose that we use this
// Based on lib.es6.d.ts
interface PromiseConstructor {
new <T>(executor: (resolve: (value?: T | PromiseLike<T>) => void, reject: (reason?: any) => void) => void): Promise<T>;
reject(reason: any): Promise<never>;
all<T>(values: (T | PromiseLike<T>)[]): Promise<T[]>;
}
/* @internal */
declare var Promise: PromiseConstructor; // eslint-disable-line no-var
/* @internal */
namespace ts {
// These utilities are common to multiple language service features.
//#region
export const scanner: Scanner = createScanner(ScriptTarget.Latest, /*skipTrivia*/ true);
export const enum SemanticMeaning {
None = 0x0,
Value = 0x1,
Type = 0x2,
Namespace = 0x4,
All = Value | Type | Namespace
}
export function getMeaningFromDeclaration(node: Node): SemanticMeaning {
switch (node.kind) {
case SyntaxKind.VariableDeclaration:
return isInJSFile(node) && getJSDocEnumTag(node) ? SemanticMeaning.All : SemanticMeaning.Value;
case SyntaxKind.Parameter:
case SyntaxKind.BindingElement:
case SyntaxKind.PropertyDeclaration:
case SyntaxKind.PropertySignature:
case SyntaxKind.PropertyAssignment:
case SyntaxKind.ShorthandPropertyAssignment:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.CatchClause:
case SyntaxKind.JsxAttribute:
return SemanticMeaning.Value;
case SyntaxKind.TypeParameter:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.TypeAliasDeclaration:
case SyntaxKind.TypeLiteral:
return SemanticMeaning.Type;
case SyntaxKind.JSDocTypedefTag:
// If it has no name node, it shares the name with the value declaration below it.
return (node as JSDocTypedefTag).name === undefined ? SemanticMeaning.Value | SemanticMeaning.Type : SemanticMeaning.Type;
case SyntaxKind.EnumMember:
case SyntaxKind.ClassDeclaration:
return SemanticMeaning.Value | SemanticMeaning.Type;
case SyntaxKind.ModuleDeclaration:
if (isAmbientModule(node as ModuleDeclaration)) {
return SemanticMeaning.Namespace | SemanticMeaning.Value;
}
else if (getModuleInstanceState(node as ModuleDeclaration) === ModuleInstanceState.Instantiated) {
return SemanticMeaning.Namespace | SemanticMeaning.Value;
}
else {
return SemanticMeaning.Namespace;
}
case SyntaxKind.EnumDeclaration:
case SyntaxKind.NamedImports:
case SyntaxKind.ImportSpecifier:
case SyntaxKind.ImportEqualsDeclaration:
case SyntaxKind.ImportDeclaration:
case SyntaxKind.ExportAssignment:
case SyntaxKind.ExportDeclaration:
return SemanticMeaning.All;
// An external module can be a Value
case SyntaxKind.SourceFile:
return SemanticMeaning.Namespace | SemanticMeaning.Value;
}
return SemanticMeaning.All;
}
export function getMeaningFromLocation(node: Node): SemanticMeaning {
node = getAdjustedReferenceLocation(node);
const parent = node.parent;
if (node.kind === SyntaxKind.SourceFile) {
return SemanticMeaning.Value;
}
else if (isExportAssignment(parent)
|| isExportSpecifier(parent)
|| isExternalModuleReference(parent)
|| isImportSpecifier(parent)
|| isImportClause(parent)
|| isImportEqualsDeclaration(parent) && node === parent.name) {
return SemanticMeaning.All;
}
else if (isInRightSideOfInternalImportEqualsDeclaration(node)) {
return getMeaningFromRightHandSideOfImportEquals(node as Identifier);
}
else if (isDeclarationName(node)) {
return getMeaningFromDeclaration(parent);
}
else if (isEntityName(node) && findAncestor(node, or(isJSDocNameReference, isJSDocLinkLike, isJSDocMemberName))) {
return SemanticMeaning.All;
}
else if (isTypeReference(node)) {
return SemanticMeaning.Type;
}
else if (isNamespaceReference(node)) {
return SemanticMeaning.Namespace;
}
else if (isTypeParameterDeclaration(parent)) {
Debug.assert(isJSDocTemplateTag(parent.parent)); // Else would be handled by isDeclarationName
return SemanticMeaning.Type;
}
else if (isLiteralTypeNode(parent)) {
// This might be T["name"], which is actually referencing a property and not a type. So allow both meanings.
return SemanticMeaning.Type | SemanticMeaning.Value;
}
else {
return SemanticMeaning.Value;
}
}
function getMeaningFromRightHandSideOfImportEquals(node: Node): SemanticMeaning {
// import a = |b|; // Namespace
// import a = |b.c|; // Value, type, namespace
// import a = |b.c|.d; // Namespace
const name = node.kind === SyntaxKind.QualifiedName ? node : isQualifiedName(node.parent) && node.parent.right === node ? node.parent : undefined;
return name && name.parent.kind === SyntaxKind.ImportEqualsDeclaration ? SemanticMeaning.All : SemanticMeaning.Namespace;
}
export function isInRightSideOfInternalImportEqualsDeclaration(node: Node) {
while (node.parent.kind === SyntaxKind.QualifiedName) {
node = node.parent;
}
return isInternalModuleImportEqualsDeclaration(node.parent) && node.parent.moduleReference === node;
}
function isNamespaceReference(node: Node): boolean {
return isQualifiedNameNamespaceReference(node) || isPropertyAccessNamespaceReference(node);
}
function isQualifiedNameNamespaceReference(node: Node): boolean {
let root = node;
let isLastClause = true;
if (root.parent.kind === SyntaxKind.QualifiedName) {
while (root.parent && root.parent.kind === SyntaxKind.QualifiedName) {
root = root.parent;
}
isLastClause = (root as QualifiedName).right === node;
}
return root.parent.kind === SyntaxKind.TypeReference && !isLastClause;
}
function isPropertyAccessNamespaceReference(node: Node): boolean {
let root = node;
let isLastClause = true;
if (root.parent.kind === SyntaxKind.PropertyAccessExpression) {
while (root.parent && root.parent.kind === SyntaxKind.PropertyAccessExpression) {
root = root.parent;
}
isLastClause = (root as PropertyAccessExpression).name === node;
}
if (!isLastClause && root.parent.kind === SyntaxKind.ExpressionWithTypeArguments && root.parent.parent.kind === SyntaxKind.HeritageClause) {
const decl = root.parent.parent.parent;
return (decl.kind === SyntaxKind.ClassDeclaration && (root.parent.parent as HeritageClause).token === SyntaxKind.ImplementsKeyword) ||
(decl.kind === SyntaxKind.InterfaceDeclaration && (root.parent.parent as HeritageClause).token === SyntaxKind.ExtendsKeyword);
}
return false;
}
function isTypeReference(node: Node): boolean {
if (isRightSideOfQualifiedNameOrPropertyAccess(node)) {
node = node.parent;
}
switch (node.kind) {
case SyntaxKind.ThisKeyword:
return !isExpressionNode(node);
case SyntaxKind.ThisType:
return true;
}
switch (node.parent.kind) {
case SyntaxKind.TypeReference:
return true;
case SyntaxKind.ImportType:
return !(node.parent as ImportTypeNode).isTypeOf;
case SyntaxKind.ExpressionWithTypeArguments:
return !isExpressionWithTypeArgumentsInClassExtendsClause(node.parent as ExpressionWithTypeArguments);
}
return false;
}
export function isCallExpressionTarget(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isCallExpression, selectExpressionOfCallOrNewExpressionOrDecorator, includeElementAccess, skipPastOuterExpressions);
}
export function isNewExpressionTarget(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isNewExpression, selectExpressionOfCallOrNewExpressionOrDecorator, includeElementAccess, skipPastOuterExpressions);
}
export function isCallOrNewExpressionTarget(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isCallOrNewExpression, selectExpressionOfCallOrNewExpressionOrDecorator, includeElementAccess, skipPastOuterExpressions);
}
export function isTaggedTemplateTag(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isTaggedTemplateExpression, selectTagOfTaggedTemplateExpression, includeElementAccess, skipPastOuterExpressions);
}
export function isDecoratorTarget(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isDecorator, selectExpressionOfCallOrNewExpressionOrDecorator, includeElementAccess, skipPastOuterExpressions);
}
export function isJsxOpeningLikeElementTagName(node: Node, includeElementAccess = false, skipPastOuterExpressions = false): boolean {
return isCalleeWorker(node, isJsxOpeningLikeElement, selectTagNameOfJsxOpeningLikeElement, includeElementAccess, skipPastOuterExpressions);
}
function selectExpressionOfCallOrNewExpressionOrDecorator(node: CallExpression | NewExpression | Decorator) {
return node.expression;
}
function selectTagOfTaggedTemplateExpression(node: TaggedTemplateExpression) {
return node.tag;
}
function selectTagNameOfJsxOpeningLikeElement(node: JsxOpeningLikeElement) {
return node.tagName;
}
function isCalleeWorker<T extends CallExpression | NewExpression | TaggedTemplateExpression | Decorator | JsxOpeningLikeElement>(node: Node, pred: (node: Node) => node is T, calleeSelector: (node: T) => Expression, includeElementAccess: boolean, skipPastOuterExpressions: boolean) {
let target = includeElementAccess ? climbPastPropertyOrElementAccess(node) : climbPastPropertyAccess(node);
if (skipPastOuterExpressions) {
target = skipOuterExpressions(target);
}
return !!target && !!target.parent && pred(target.parent) && calleeSelector(target.parent) === target;
}
export function climbPastPropertyAccess(node: Node) {
return isRightSideOfPropertyAccess(node) ? node.parent : node;
}
export function climbPastPropertyOrElementAccess(node: Node) {
return isRightSideOfPropertyAccess(node) || isArgumentExpressionOfElementAccess(node) ? node.parent : node;
}
export function getTargetLabel(referenceNode: Node, labelName: string): Identifier | undefined {
while (referenceNode) {
if (referenceNode.kind === SyntaxKind.LabeledStatement && (referenceNode as LabeledStatement).label.escapedText === labelName) {
return (referenceNode as LabeledStatement).label;
}
referenceNode = referenceNode.parent;
}
return undefined;
}
export function hasPropertyAccessExpressionWithName(node: CallExpression, funcName: string): boolean {
if (!isPropertyAccessExpression(node.expression)) {
return false;
}
return node.expression.name.text === funcName;
}
export function isJumpStatementTarget(node: Node): node is Identifier & { parent: BreakOrContinueStatement } {
return isIdentifier(node) && tryCast(node.parent, isBreakOrContinueStatement)?.label === node;
}
export function isLabelOfLabeledStatement(node: Node): node is Identifier {
return isIdentifier(node) && tryCast(node.parent, isLabeledStatement)?.label === node;
}
export function isLabelName(node: Node): boolean {
return isLabelOfLabeledStatement(node) || isJumpStatementTarget(node);
}
export function isTagName(node: Node): boolean {
return tryCast(node.parent, isJSDocTag)?.tagName === node;
}
export function isRightSideOfQualifiedName(node: Node) {
return tryCast(node.parent, isQualifiedName)?.right === node;
}
export function isRightSideOfPropertyAccess(node: Node) {
return tryCast(node.parent, isPropertyAccessExpression)?.name === node;
}
export function isArgumentExpressionOfElementAccess(node: Node) {
return tryCast(node.parent, isElementAccessExpression)?.argumentExpression === node;
}
export function isNameOfModuleDeclaration(node: Node) {
return tryCast(node.parent, isModuleDeclaration)?.name === node;
}
export function isNameOfFunctionDeclaration(node: Node): boolean {
return isIdentifier(node) && tryCast(node.parent, isFunctionLike)?.name === node;
}
export function isLiteralNameOfPropertyDeclarationOrIndexAccess(node: StringLiteral | NumericLiteral | NoSubstitutionTemplateLiteral): boolean {
switch (node.parent.kind) {
case SyntaxKind.PropertyDeclaration:
case SyntaxKind.PropertySignature:
case SyntaxKind.PropertyAssignment:
case SyntaxKind.EnumMember:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.ModuleDeclaration:
return getNameOfDeclaration(node.parent as Declaration) === node;
case SyntaxKind.ElementAccessExpression:
return (node.parent as ElementAccessExpression).argumentExpression === node;
case SyntaxKind.ComputedPropertyName:
return true;
case SyntaxKind.LiteralType:
return node.parent.parent.kind === SyntaxKind.IndexedAccessType;
default:
return false;
}
}
export function isExpressionOfExternalModuleImportEqualsDeclaration(node: Node) {
return isExternalModuleImportEqualsDeclaration(node.parent.parent) &&
getExternalModuleImportEqualsDeclarationExpression(node.parent.parent) === node;
}
export function getContainerNode(node: Node): Declaration | undefined {
if (isJSDocTypeAlias(node)) {
// This doesn't just apply to the node immediately under the comment, but to everything in its parent's scope.
// node.parent = the JSDoc comment, node.parent.parent = the node having the comment.
// Then we get parent again in the loop.
node = node.parent.parent;
}
while (true) {
node = node.parent;
if (!node) {
return undefined;
}
switch (node.kind) {
case SyntaxKind.SourceFile:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.ModuleDeclaration:
return node as Declaration;
}
}
}
export function getNodeKind(node: Node): ScriptElementKind {
switch (node.kind) {
case SyntaxKind.SourceFile:
return isExternalModule(node as SourceFile) ? ScriptElementKind.moduleElement : ScriptElementKind.scriptElement;
case SyntaxKind.ModuleDeclaration:
return ScriptElementKind.moduleElement;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.ClassExpression:
return ScriptElementKind.classElement;
case SyntaxKind.InterfaceDeclaration: return ScriptElementKind.interfaceElement;
case SyntaxKind.TypeAliasDeclaration:
case SyntaxKind.JSDocCallbackTag:
case SyntaxKind.JSDocTypedefTag:
return ScriptElementKind.typeElement;
case SyntaxKind.EnumDeclaration: return ScriptElementKind.enumElement;
case SyntaxKind.VariableDeclaration:
return getKindOfVariableDeclaration(node as VariableDeclaration);
case SyntaxKind.BindingElement:
return getKindOfVariableDeclaration(getRootDeclaration(node) as VariableDeclaration);
case SyntaxKind.ArrowFunction:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
return ScriptElementKind.functionElement;
case SyntaxKind.GetAccessor: return ScriptElementKind.memberGetAccessorElement;
case SyntaxKind.SetAccessor: return ScriptElementKind.memberSetAccessorElement;
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
return ScriptElementKind.memberFunctionElement;
case SyntaxKind.PropertyAssignment:
const { initializer } = node as PropertyAssignment;
return isFunctionLike(initializer) ? ScriptElementKind.memberFunctionElement : ScriptElementKind.memberVariableElement;
case SyntaxKind.PropertyDeclaration:
case SyntaxKind.PropertySignature:
case SyntaxKind.ShorthandPropertyAssignment:
case SyntaxKind.SpreadAssignment:
return ScriptElementKind.memberVariableElement;
case SyntaxKind.IndexSignature: return ScriptElementKind.indexSignatureElement;
case SyntaxKind.ConstructSignature: return ScriptElementKind.constructSignatureElement;
case SyntaxKind.CallSignature: return ScriptElementKind.callSignatureElement;
case SyntaxKind.Constructor:
case SyntaxKind.ClassStaticBlockDeclaration:
return ScriptElementKind.constructorImplementationElement;
case SyntaxKind.TypeParameter: return ScriptElementKind.typeParameterElement;
case SyntaxKind.EnumMember: return ScriptElementKind.enumMemberElement;
case SyntaxKind.Parameter: return hasSyntacticModifier(node, ModifierFlags.ParameterPropertyModifier) ? ScriptElementKind.memberVariableElement : ScriptElementKind.parameterElement;
case SyntaxKind.ImportEqualsDeclaration:
case SyntaxKind.ImportSpecifier:
case SyntaxKind.ExportSpecifier:
case SyntaxKind.NamespaceImport:
case SyntaxKind.NamespaceExport:
return ScriptElementKind.alias;
case SyntaxKind.BinaryExpression:
const kind = getAssignmentDeclarationKind(node as BinaryExpression);
const { right } = node as BinaryExpression;
switch (kind) {
case AssignmentDeclarationKind.ObjectDefinePropertyValue:
case AssignmentDeclarationKind.ObjectDefinePropertyExports:
case AssignmentDeclarationKind.ObjectDefinePrototypeProperty:
case AssignmentDeclarationKind.None:
return ScriptElementKind.unknown;
case AssignmentDeclarationKind.ExportsProperty:
case AssignmentDeclarationKind.ModuleExports:
const rightKind = getNodeKind(right);
return rightKind === ScriptElementKind.unknown ? ScriptElementKind.constElement : rightKind;
case AssignmentDeclarationKind.PrototypeProperty:
return isFunctionExpression(right) ? ScriptElementKind.memberFunctionElement : ScriptElementKind.memberVariableElement;
case AssignmentDeclarationKind.ThisProperty:
return ScriptElementKind.memberVariableElement; // property
case AssignmentDeclarationKind.Property:
// static method / property
return isFunctionExpression(right) ? ScriptElementKind.memberFunctionElement : ScriptElementKind.memberVariableElement;
case AssignmentDeclarationKind.Prototype:
return ScriptElementKind.localClassElement;
default: {
assertType<never>(kind);
return ScriptElementKind.unknown;
}
}
case SyntaxKind.Identifier:
return isImportClause(node.parent) ? ScriptElementKind.alias : ScriptElementKind.unknown;
case SyntaxKind.ExportAssignment:
const scriptKind = getNodeKind((node as ExportAssignment).expression);
// If the expression didn't come back with something (like it does for an identifiers)
return scriptKind === ScriptElementKind.unknown ? ScriptElementKind.constElement : scriptKind;
default:
return ScriptElementKind.unknown;
}
function getKindOfVariableDeclaration(v: VariableDeclaration): ScriptElementKind {
return isVarConst(v)
? ScriptElementKind.constElement
: isLet(v)
? ScriptElementKind.letElement
: ScriptElementKind.variableElement;
}
}
export function isThis(node: Node): boolean {
switch (node.kind) {
case SyntaxKind.ThisKeyword:
// case SyntaxKind.ThisType: TODO: GH#9267
return true;
case SyntaxKind.Identifier:
// 'this' as a parameter
return identifierIsThisKeyword(node as Identifier) && node.parent.kind === SyntaxKind.Parameter;
default:
return false;
}
}
// Matches the beginning of a triple slash directive
const tripleSlashDirectivePrefixRegex = /^\/\/\/\s*</;
export interface ListItemInfo {
listItemIndex: number;
list: Node;
}
export function getLineStartPositionForPosition(position: number, sourceFile: SourceFileLike): number {
const lineStarts = getLineStarts(sourceFile);
const line = sourceFile.getLineAndCharacterOfPosition(position).line;
return lineStarts[line];
}
export function rangeContainsRange(r1: TextRange, r2: TextRange): boolean {
return startEndContainsRange(r1.pos, r1.end, r2);
}
export function rangeContainsRangeExclusive(r1: TextRange, r2: TextRange): boolean {
return rangeContainsPositionExclusive(r1, r2.pos) && rangeContainsPositionExclusive(r1, r2.end);
}
export function rangeContainsPosition(r: TextRange, pos: number): boolean {
return r.pos <= pos && pos <= r.end;
}
export function rangeContainsPositionExclusive(r: TextRange, pos: number) {
return r.pos < pos && pos < r.end;
}
export function startEndContainsRange(start: number, end: number, range: TextRange): boolean {
return start <= range.pos && end >= range.end;
}
export function rangeContainsStartEnd(range: TextRange, start: number, end: number): boolean {
return range.pos <= start && range.end >= end;
}
export function rangeOverlapsWithStartEnd(r1: TextRange, start: number, end: number) {
return startEndOverlapsWithStartEnd(r1.pos, r1.end, start, end);
}
export function nodeOverlapsWithStartEnd(node: Node, sourceFile: SourceFile, start: number, end: number) {
return startEndOverlapsWithStartEnd(node.getStart(sourceFile), node.end, start, end);
}
export function startEndOverlapsWithStartEnd(start1: number, end1: number, start2: number, end2: number) {
const start = Math.max(start1, start2);
const end = Math.min(end1, end2);
return start < end;
}
/**
* Assumes `candidate.start <= position` holds.
*/
export function positionBelongsToNode(candidate: Node, position: number, sourceFile: SourceFile): boolean {
Debug.assert(candidate.pos <= position);
return position < candidate.end || !isCompletedNode(candidate, sourceFile);
}
function isCompletedNode(n: Node | undefined, sourceFile: SourceFile): boolean {
if (n === undefined || nodeIsMissing(n)) {
return false;
}
switch (n.kind) {
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.ObjectBindingPattern:
case SyntaxKind.TypeLiteral:
case SyntaxKind.Block:
case SyntaxKind.ModuleBlock:
case SyntaxKind.CaseBlock:
case SyntaxKind.NamedImports:
case SyntaxKind.NamedExports:
return nodeEndsWith(n, SyntaxKind.CloseBraceToken, sourceFile);
case SyntaxKind.CatchClause:
return isCompletedNode((n as CatchClause).block, sourceFile);
case SyntaxKind.NewExpression:
if (!(n as NewExpression).arguments) {
return true;
}
// falls through
case SyntaxKind.CallExpression:
case SyntaxKind.ParenthesizedExpression:
case SyntaxKind.ParenthesizedType:
return nodeEndsWith(n, SyntaxKind.CloseParenToken, sourceFile);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
return isCompletedNode((n as SignatureDeclaration).type, sourceFile);
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.CallSignature:
case SyntaxKind.ArrowFunction:
if ((n as FunctionLikeDeclaration).body) {
return isCompletedNode((n as FunctionLikeDeclaration).body, sourceFile);
}
if ((n as FunctionLikeDeclaration).type) {
return isCompletedNode((n as FunctionLikeDeclaration).type, sourceFile);
}
// Even though type parameters can be unclosed, we can get away with
// having at least a closing paren.
return hasChildOfKind(n, SyntaxKind.CloseParenToken, sourceFile);
case SyntaxKind.ModuleDeclaration:
return !!(n as ModuleDeclaration).body && isCompletedNode((n as ModuleDeclaration).body, sourceFile);
case SyntaxKind.IfStatement:
if ((n as IfStatement).elseStatement) {
return isCompletedNode((n as IfStatement).elseStatement, sourceFile);
}
return isCompletedNode((n as IfStatement).thenStatement, sourceFile);
case SyntaxKind.ExpressionStatement:
return isCompletedNode((n as ExpressionStatement).expression, sourceFile) ||
hasChildOfKind(n, SyntaxKind.SemicolonToken, sourceFile);
case SyntaxKind.ArrayLiteralExpression:
case SyntaxKind.ArrayBindingPattern:
case SyntaxKind.ElementAccessExpression:
case SyntaxKind.ComputedPropertyName:
case SyntaxKind.TupleType:
return nodeEndsWith(n, SyntaxKind.CloseBracketToken, sourceFile);
case SyntaxKind.IndexSignature:
if ((n as IndexSignatureDeclaration).type) {
return isCompletedNode((n as IndexSignatureDeclaration).type, sourceFile);
}
return hasChildOfKind(n, SyntaxKind.CloseBracketToken, sourceFile);
case SyntaxKind.CaseClause:
case SyntaxKind.DefaultClause:
// there is no such thing as terminator token for CaseClause/DefaultClause so for simplicity always consider them non-completed
return false;
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
case SyntaxKind.ForOfStatement:
case SyntaxKind.WhileStatement:
return isCompletedNode((n as IterationStatement).statement, sourceFile);
case SyntaxKind.DoStatement:
// rough approximation: if DoStatement has While keyword - then if node is completed is checking the presence of ')';
return hasChildOfKind(n, SyntaxKind.WhileKeyword, sourceFile)
? nodeEndsWith(n, SyntaxKind.CloseParenToken, sourceFile)
: isCompletedNode((n as DoStatement).statement, sourceFile);
case SyntaxKind.TypeQuery:
return isCompletedNode((n as TypeQueryNode).exprName, sourceFile);
case SyntaxKind.TypeOfExpression:
case SyntaxKind.DeleteExpression:
case SyntaxKind.VoidExpression:
case SyntaxKind.YieldExpression:
case SyntaxKind.SpreadElement:
const unaryWordExpression = n as (TypeOfExpression | DeleteExpression | VoidExpression | YieldExpression | SpreadElement);
return isCompletedNode(unaryWordExpression.expression, sourceFile);
case SyntaxKind.TaggedTemplateExpression:
return isCompletedNode((n as TaggedTemplateExpression).template, sourceFile);
case SyntaxKind.TemplateExpression:
const lastSpan = lastOrUndefined((n as TemplateExpression).templateSpans);
return isCompletedNode(lastSpan, sourceFile);
case SyntaxKind.TemplateSpan:
return nodeIsPresent((n as TemplateSpan).literal);
case SyntaxKind.ExportDeclaration:
case SyntaxKind.ImportDeclaration:
return nodeIsPresent((n as ExportDeclaration | ImportDeclaration).moduleSpecifier);
case SyntaxKind.PrefixUnaryExpression:
return isCompletedNode((n as PrefixUnaryExpression).operand, sourceFile);
case SyntaxKind.BinaryExpression:
return isCompletedNode((n as BinaryExpression).right, sourceFile);
case SyntaxKind.ConditionalExpression:
return isCompletedNode((n as ConditionalExpression).whenFalse, sourceFile);
default:
return true;
}
}
/*
* Checks if node ends with 'expectedLastToken'.
* If child at position 'length - 1' is 'SemicolonToken' it is skipped and 'expectedLastToken' is compared with child at position 'length - 2'.
*/
function nodeEndsWith(n: Node, expectedLastToken: SyntaxKind, sourceFile: SourceFile): boolean {
const children = n.getChildren(sourceFile);
if (children.length) {
const lastChild = last(children);
if (lastChild.kind === expectedLastToken) {
return true;
}
else if (lastChild.kind === SyntaxKind.SemicolonToken && children.length !== 1) {
return children[children.length - 2].kind === expectedLastToken;
}
}
return false;
}
export function findListItemInfo(node: Node): ListItemInfo | undefined {
const list = findContainingList(node);
// It is possible at this point for syntaxList to be undefined, either if
// node.parent had no list child, or if none of its list children contained
// the span of node. If this happens, return undefined. The caller should
// handle this case.
if (!list) {
return undefined;
}
const children = list.getChildren();
const listItemIndex = indexOfNode(children, node);
return {
listItemIndex,
list
};
}
export function hasChildOfKind(n: Node, kind: SyntaxKind, sourceFile: SourceFile): boolean {
return !!findChildOfKind(n, kind, sourceFile);
}
export function findChildOfKind<T extends Node>(n: Node, kind: T["kind"], sourceFile: SourceFileLike): T | undefined {
return find(n.getChildren(sourceFile), (c): c is T => c.kind === kind);
}
export function findContainingList(node: Node): SyntaxList | undefined {
// The node might be a list element (nonsynthetic) or a comma (synthetic). Either way, it will
// be parented by the container of the SyntaxList, not the SyntaxList itself.
// In order to find the list item index, we first need to locate SyntaxList itself and then search
// for the position of the relevant node (or comma).
const syntaxList = find(node.parent.getChildren(), (c): c is SyntaxList => isSyntaxList(c) && rangeContainsRange(c, node));
// Either we didn't find an appropriate list, or the list must contain us.
Debug.assert(!syntaxList || contains(syntaxList.getChildren(), node));
return syntaxList;
}
function isDefaultModifier(node: Node) {
return node.kind === SyntaxKind.DefaultKeyword;
}
function isClassKeyword(node: Node) {
return node.kind === SyntaxKind.ClassKeyword;
}
function isFunctionKeyword(node: Node) {
return node.kind === SyntaxKind.FunctionKeyword;
}
function getAdjustedLocationForClass(node: ClassDeclaration | ClassExpression) {
if (isNamedDeclaration(node)) {
return node.name;
}
if (isClassDeclaration(node)) {
// for class and function declarations, use the `default` modifier
// when the declaration is unnamed.
const defaultModifier = node.modifiers && find(node.modifiers, isDefaultModifier);
if (defaultModifier) return defaultModifier;
}
if (isClassExpression(node)) {
// for class expressions, use the `class` keyword when the class is unnamed
const classKeyword = find(node.getChildren(), isClassKeyword);
if (classKeyword) return classKeyword;
}
}
function getAdjustedLocationForFunction(node: FunctionDeclaration | FunctionExpression) {
if (isNamedDeclaration(node)) {
return node.name;
}
if (isFunctionDeclaration(node)) {
// for class and function declarations, use the `default` modifier
// when the declaration is unnamed.
const defaultModifier = find(node.modifiers!, isDefaultModifier);
if (defaultModifier) return defaultModifier;
}
if (isFunctionExpression(node)) {
// for function expressions, use the `function` keyword when the function is unnamed
const functionKeyword = find(node.getChildren(), isFunctionKeyword);
if (functionKeyword) return functionKeyword;
}
}
function getAncestorTypeNode(node: Node) {
let lastTypeNode: TypeNode | undefined;
findAncestor(node, a => {
if (isTypeNode(a)) {
lastTypeNode = a;
}
return !isQualifiedName(a.parent) && !isTypeNode(a.parent) && !isTypeElement(a.parent);
});
return lastTypeNode;
}
export function getContextualTypeFromParentOrAncestorTypeNode(node: Expression, checker: TypeChecker): Type | undefined {
const contextualType = getContextualTypeFromParent(node, checker);
if (contextualType) return contextualType;
const ancestorTypeNode = getAncestorTypeNode(node);
return ancestorTypeNode && checker.getTypeAtLocation(ancestorTypeNode);
}
function getAdjustedLocationForDeclaration(node: Node, forRename: boolean) {
if (!forRename) {
switch (node.kind) {
case SyntaxKind.ClassDeclaration:
case SyntaxKind.ClassExpression:
return getAdjustedLocationForClass(node as ClassDeclaration | ClassExpression);
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
return getAdjustedLocationForFunction(node as FunctionDeclaration | FunctionExpression);
}
}
if (isNamedDeclaration(node)) {
return node.name;
}
}
function getAdjustedLocationForImportDeclaration(node: ImportDeclaration, forRename: boolean) {
if (node.importClause) {
if (node.importClause.name && node.importClause.namedBindings) {
// do not adjust if we have both a name and named bindings
return;
}
// /**/import [|name|] from ...;
// import /**/type [|name|] from ...;
if (node.importClause.name) {
return node.importClause.name;
}
// /**/import { [|name|] } from ...;
// /**/import { propertyName as [|name|] } from ...;
// /**/import * as [|name|] from ...;
// import /**/type { [|name|] } from ...;
// import /**/type { propertyName as [|name|] } from ...;
// import /**/type * as [|name|] from ...;
if (node.importClause.namedBindings) {
if (isNamedImports(node.importClause.namedBindings)) {
// do nothing if there is more than one binding
const onlyBinding = singleOrUndefined(node.importClause.namedBindings.elements);
if (!onlyBinding) {
return;
}
return onlyBinding.name;
}
else if (isNamespaceImport(node.importClause.namedBindings)) {
return node.importClause.namedBindings.name;
}
}
}
if (!forRename) {
// /**/import "[|module|]";
// /**/import ... from "[|module|]";
// import /**/type ... from "[|module|]";
return node.moduleSpecifier;
}
}
function getAdjustedLocationForExportDeclaration(node: ExportDeclaration, forRename: boolean) {
if (node.exportClause) {
// /**/export { [|name|] } ...
// /**/export { propertyName as [|name|] } ...
// /**/export * as [|name|] ...
// export /**/type { [|name|] } from ...
// export /**/type { propertyName as [|name|] } from ...
// export /**/type * as [|name|] ...
if (isNamedExports(node.exportClause)) {
// do nothing if there is more than one binding
const onlyBinding = singleOrUndefined(node.exportClause.elements);
if (!onlyBinding) {
return;
}
return node.exportClause.elements[0].name;
}
else if (isNamespaceExport(node.exportClause)) {
return node.exportClause.name;
}
}
if (!forRename) {
// /**/export * from "[|module|]";
// export /**/type * from "[|module|]";
return node.moduleSpecifier;
}
}
function getAdjustedLocationForHeritageClause(node: HeritageClause) {
// /**/extends [|name|]
// /**/implements [|name|]
if (node.types.length === 1) {
return node.types[0].expression;
}
// /**/extends name1, name2 ...
// /**/implements name1, name2 ...
}
function getAdjustedLocation(node: Node, forRename: boolean): Node {
const { parent } = node;
// /**/<modifier> [|name|] ...
// /**/<modifier> <class|interface|type|enum|module|namespace|function|get|set> [|name|] ...
// /**/<class|interface|type|enum|module|namespace|function|get|set> [|name|] ...
// /**/import [|name|] = ...
//
// NOTE: If the node is a modifier, we don't adjust its location if it is the `default` modifier as that is handled
// specially by `getSymbolAtLocation`.
if (isModifier(node) && (forRename || node.kind !== SyntaxKind.DefaultKeyword) ? contains(parent.modifiers, node) :
node.kind === SyntaxKind.ClassKeyword ? isClassDeclaration(parent) || isClassExpression(node) :
node.kind === SyntaxKind.FunctionKeyword ? isFunctionDeclaration(parent) || isFunctionExpression(node) :
node.kind === SyntaxKind.InterfaceKeyword ? isInterfaceDeclaration(parent) :
node.kind === SyntaxKind.EnumKeyword ? isEnumDeclaration(parent) :
node.kind === SyntaxKind.TypeKeyword ? isTypeAliasDeclaration(parent) :
node.kind === SyntaxKind.NamespaceKeyword || node.kind === SyntaxKind.ModuleKeyword ? isModuleDeclaration(parent) :
node.kind === SyntaxKind.ImportKeyword ? isImportEqualsDeclaration(parent) :
node.kind === SyntaxKind.GetKeyword ? isGetAccessorDeclaration(parent) :
node.kind === SyntaxKind.SetKeyword && isSetAccessorDeclaration(parent)) {
const location = getAdjustedLocationForDeclaration(parent, forRename);
if (location) {
return location;
}
}
// /**/<var|let|const> [|name|] ...
if ((node.kind === SyntaxKind.VarKeyword || node.kind === SyntaxKind.ConstKeyword || node.kind === SyntaxKind.LetKeyword) &&
isVariableDeclarationList(parent) && parent.declarations.length === 1) {
const decl = parent.declarations[0];
if (isIdentifier(decl.name)) {
return decl.name;
}
}
if (node.kind === SyntaxKind.TypeKeyword) {
// import /**/type [|name|] from ...;
// import /**/type { [|name|] } from ...;
// import /**/type { propertyName as [|name|] } from ...;
// import /**/type ... from "[|module|]";
if (isImportClause(parent) && parent.isTypeOnly) {
const location = getAdjustedLocationForImportDeclaration(parent.parent, forRename);
if (location) {
return location;
}
}
// export /**/type { [|name|] } from ...;
// export /**/type { propertyName as [|name|] } from ...;
// export /**/type * from "[|module|]";
// export /**/type * as ... from "[|module|]";
if (isExportDeclaration(parent) && parent.isTypeOnly) {
const location = getAdjustedLocationForExportDeclaration(parent, forRename);
if (location) {
return location;
}
}
}
// import { propertyName /**/as [|name|] } ...
// import * /**/as [|name|] ...
// export { propertyName /**/as [|name|] } ...
// export * /**/as [|name|] ...
if (node.kind === SyntaxKind.AsKeyword) {
if (isImportSpecifier(parent) && parent.propertyName ||
isExportSpecifier(parent) && parent.propertyName ||
isNamespaceImport(parent) ||
isNamespaceExport(parent)) {
return parent.name;
}
if (isExportDeclaration(parent) && parent.exportClause && isNamespaceExport(parent.exportClause)) {
return parent.exportClause.name;
}
}
// /**/import [|name|] from ...;
// /**/import { [|name|] } from ...;
// /**/import { propertyName as [|name|] } from ...;
// /**/import ... from "[|module|]";
// /**/import "[|module|]";
if (node.kind === SyntaxKind.ImportKeyword && isImportDeclaration(parent)) {
const location = getAdjustedLocationForImportDeclaration(parent, forRename);
if (location) {
return location;
}
}
if (node.kind === SyntaxKind.ExportKeyword) {
// /**/export { [|name|] } ...;
// /**/export { propertyName as [|name|] } ...;
// /**/export * from "[|module|]";
// /**/export * as ... from "[|module|]";
if (isExportDeclaration(parent)) {
const location = getAdjustedLocationForExportDeclaration(parent, forRename);
if (location) {
return location;
}
}
// NOTE: We don't adjust the location of the `default` keyword as that is handled specially by `getSymbolAtLocation`.
// /**/export default [|name|];
// /**/export = [|name|];
if (isExportAssignment(parent)) {
return skipOuterExpressions(parent.expression);
}
}
// import name = /**/require("[|module|]");
if (node.kind === SyntaxKind.RequireKeyword && isExternalModuleReference(parent)) {
return parent.expression;
}
// import ... /**/from "[|module|]";
// export ... /**/from "[|module|]";
if (node.kind === SyntaxKind.FromKeyword && (isImportDeclaration(parent) || isExportDeclaration(parent)) && parent.moduleSpecifier) {
return parent.moduleSpecifier;
}
// class ... /**/extends [|name|] ...
// class ... /**/implements [|name|] ...
// class ... /**/implements name1, name2 ...
// interface ... /**/extends [|name|] ...
// interface ... /**/extends name1, name2 ...
if ((node.kind === SyntaxKind.ExtendsKeyword || node.kind === SyntaxKind.ImplementsKeyword) && isHeritageClause(parent) && parent.token === node.kind) {
const location = getAdjustedLocationForHeritageClause(parent);
if (location) {
return location;
}
}
if (node.kind === SyntaxKind.ExtendsKeyword) {
// ... <T /**/extends [|U|]> ...
if (isTypeParameterDeclaration(parent) && parent.constraint && isTypeReferenceNode(parent.constraint)) {
return parent.constraint.typeName;
}
// ... T /**/extends [|U|] ? ...
if (isConditionalTypeNode(parent) && isTypeReferenceNode(parent.extendsType)) {
return parent.extendsType.typeName;
}
}
// ... T extends /**/infer [|U|] ? ...
if (node.kind === SyntaxKind.InferKeyword && isInferTypeNode(parent)) {
return parent.typeParameter.name;
}
// { [ [|K|] /**/in keyof T]: ... }
if (node.kind === SyntaxKind.InKeyword && isTypeParameterDeclaration(parent) && isMappedTypeNode(parent.parent)) {
return parent.name;
}
// /**/keyof [|T|]
if (node.kind === SyntaxKind.KeyOfKeyword && isTypeOperatorNode(parent) && parent.operator === SyntaxKind.KeyOfKeyword &&
isTypeReferenceNode(parent.type)) {
return parent.type.typeName;
}
// /**/readonly [|name|][]
if (node.kind === SyntaxKind.ReadonlyKeyword && isTypeOperatorNode(parent) && parent.operator === SyntaxKind.ReadonlyKeyword &&
isArrayTypeNode(parent.type) && isTypeReferenceNode(parent.type.elementType)) {
return parent.type.elementType.typeName;
}
if (!forRename) {
// /**/new [|name|]
// /**/void [|name|]
// /**/void obj.[|name|]
// /**/typeof [|name|]
// /**/typeof obj.[|name|]
// /**/await [|name|]
// /**/await obj.[|name|]
// /**/yield [|name|]
// /**/yield obj.[|name|]
// /**/delete obj.[|name|]
if (node.kind === SyntaxKind.NewKeyword && isNewExpression(parent) ||
node.kind === SyntaxKind.VoidKeyword && isVoidExpression(parent) ||
node.kind === SyntaxKind.TypeOfKeyword && isTypeOfExpression(parent) ||
node.kind === SyntaxKind.AwaitKeyword && isAwaitExpression(parent) ||
node.kind === SyntaxKind.YieldKeyword && isYieldExpression(parent) ||
node.kind === SyntaxKind.DeleteKeyword && isDeleteExpression(parent)) {
if (parent.expression) {
return skipOuterExpressions(parent.expression);
}
}
// left /**/in [|name|]
// left /**/instanceof [|name|]
if ((node.kind === SyntaxKind.InKeyword || node.kind === SyntaxKind.InstanceOfKeyword) && isBinaryExpression(parent) && parent.operatorToken === node) {
return skipOuterExpressions(parent.right);
}
// left /**/as [|name|]
if (node.kind === SyntaxKind.AsKeyword && isAsExpression(parent) && isTypeReferenceNode(parent.type)) {
return parent.type.typeName;
}
// for (... /**/in [|name|])
// for (... /**/of [|name|])
if (node.kind === SyntaxKind.InKeyword && isForInStatement(parent) ||
node.kind === SyntaxKind.OfKeyword && isForOfStatement(parent)) {
return skipOuterExpressions(parent.expression);
}
}
return node;
}
/**
* Adjusts the location used for "find references" and "go to definition" when the cursor was not
* on a property name.
*/
export function getAdjustedReferenceLocation(node: Node): Node {
return getAdjustedLocation(node, /*forRename*/ false);
}
/**
* Adjusts the location used for "rename" when the cursor was not on a property name.
*/
export function getAdjustedRenameLocation(node: Node): Node {
return getAdjustedLocation(node, /*forRename*/ true);
}
/**
* Gets the token whose text has range [start, end) and
* position >= start and (position < end or (position === end && token is literal or keyword or identifier))
*/
export function getTouchingPropertyName(sourceFile: SourceFile, position: number): Node {
return getTouchingToken(sourceFile, position, n => isPropertyNameLiteral(n) || isKeyword(n.kind) || isPrivateIdentifier(n));
}
/**
* Returns the token if position is in [start, end).
* If position === end, returns the preceding token if includeItemAtEndPosition(previousToken) === true
*/
export function getTouchingToken(sourceFile: SourceFile, position: number, includePrecedingTokenAtEndPosition?: (n: Node) => boolean): Node {
return getTokenAtPositionWorker(sourceFile, position, /*allowPositionInLeadingTrivia*/ false, includePrecedingTokenAtEndPosition, /*includeEndPosition*/ false);
}
/** Returns a token if position is in [start-of-leading-trivia, end) */
export function getTokenAtPosition(sourceFile: SourceFile, position: number): Node {
return getTokenAtPositionWorker(sourceFile, position, /*allowPositionInLeadingTrivia*/ true, /*includePrecedingTokenAtEndPosition*/ undefined, /*includeEndPosition*/ false);
}
/** Get the token whose text contains the position */
function getTokenAtPositionWorker(sourceFile: SourceFile, position: number, allowPositionInLeadingTrivia: boolean, includePrecedingTokenAtEndPosition: ((n: Node) => boolean) | undefined, includeEndPosition: boolean): Node {
let current: Node = sourceFile;
let foundToken: Node | undefined;
outer: while (true) {
// find the child that contains 'position'
const children = current.getChildren(sourceFile);
const i = binarySearchKey(children, position, (_, i) => i, (middle, _) => {
// This last callback is more of a selector than a comparator -
// `EqualTo` causes the `middle` result to be returned
// `GreaterThan` causes recursion on the left of the middle
// `LessThan` causes recursion on the right of the middle
// Let's say you have 3 nodes, spanning positons
// pos: 1, end: 3
// pos: 3, end: 3
// pos: 3, end: 5
// and you're looking for the token at positon 3 - all 3 of these nodes are overlapping with position 3.
// In fact, there's a _good argument_ that node 2 shouldn't even be allowed to exist - depending on if
// the start or end of the ranges are considered inclusive, it's either wholly subsumed by the first or the last node.
// Unfortunately, such nodes do exist. :( - See fourslash/completionsImport_tsx.tsx - empty jsx attributes create
// a zero-length node.
// What also you may not expect is that which node we return depends on the includePrecedingTokenAtEndPosition flag.
// Specifically, if includePrecedingTokenAtEndPosition is set, we return the 1-3 node, while if it's unset, we
// return the 3-5 node. (The zero length node is never correct.) This is because the includePrecedingTokenAtEndPosition
// flag causes us to return the first node whose end position matches the position and which produces and acceptable token
// kind. Meanwhile, if includePrecedingTokenAtEndPosition is unset, we look for the first node whose start is <= the
// position and whose end is greater than the position.
const start = allowPositionInLeadingTrivia ? children[middle].getFullStart() : children[middle].getStart(sourceFile, /*includeJsDoc*/ true);
if (start > position) {
return Comparison.GreaterThan;
}
// first element whose start position is before the input and whose end position is after or equal to the input
if (nodeContainsPosition(children[middle])) {
if (children[middle - 1]) {
// we want the _first_ element that contains the position, so left-recur if the prior node also contains the position
if (nodeContainsPosition(children[middle - 1])) {
return Comparison.GreaterThan;
}
}
return Comparison.EqualTo;
}
// this complex condition makes us left-recur around a zero-length node when includePrecedingTokenAtEndPosition is set, rather than right-recur on it
if (includePrecedingTokenAtEndPosition && start === position && children[middle - 1] && children[middle - 1].getEnd() === position && nodeContainsPosition(children[middle - 1])) {
return Comparison.GreaterThan;
}
return Comparison.LessThan;
});
if (foundToken) {
return foundToken;
}
if (i >= 0 && children[i]) {
current = children[i];
continue outer;
}
return current;
}
function nodeContainsPosition(node: Node) {
const start = allowPositionInLeadingTrivia ? node.getFullStart() : node.getStart(sourceFile, /*includeJsDoc*/ true);
if (start > position) {
// If this child begins after position, then all subsequent children will as well.
return false;
}
const end = node.getEnd();
if (position < end || (position === end && (node.kind === SyntaxKind.EndOfFileToken || includeEndPosition))) {
return true;
}
else if (includePrecedingTokenAtEndPosition && end === position) {
const previousToken = findPrecedingToken(position, sourceFile, node);
if (previousToken && includePrecedingTokenAtEndPosition(previousToken)) {
foundToken = previousToken;
return true;
}
}
return false;
}
}
/**
* Returns the first token where position is in [start, end),
* excluding `JsxText` tokens containing only whitespace.
*/
export function findFirstNonJsxWhitespaceToken(sourceFile: SourceFile, position: number): Node | undefined {
let tokenAtPosition = getTokenAtPosition(sourceFile, position);
while (isWhiteSpaceOnlyJsxText(tokenAtPosition)) {
const nextToken = findNextToken(tokenAtPosition, tokenAtPosition.parent, sourceFile);
if (!nextToken) return;
tokenAtPosition = nextToken;
}
return tokenAtPosition;
}
/**
* The token on the left of the position is the token that strictly includes the position
* or sits to the left of the cursor if it is on a boundary. For example
*
* fo|o -> will return foo
* foo <comment> |bar -> will return foo
*
*/
export function findTokenOnLeftOfPosition(file: SourceFile, position: number): Node | undefined {
// Ideally, getTokenAtPosition should return a token. However, it is currently
// broken, so we do a check to make sure the result was indeed a token.
const tokenAtPosition = getTokenAtPosition(file, position);
if (isToken(tokenAtPosition) && position > tokenAtPosition.getStart(file) && position < tokenAtPosition.getEnd()) {
return tokenAtPosition;
}
return findPrecedingToken(position, file);
}
export function findNextToken(previousToken: Node, parent: Node, sourceFile: SourceFileLike): Node | undefined {
return find(parent);
function find(n: Node): Node | undefined {
if (isToken(n) && n.pos === previousToken.end) {
// this is token that starts at the end of previous token - return it
return n;
}
return firstDefined(n.getChildren(sourceFile), child => {
const shouldDiveInChildNode =
// previous token is enclosed somewhere in the child
(child.pos <= previousToken.pos && child.end > previousToken.end) ||
// previous token ends exactly at the beginning of child
(child.pos === previousToken.end);
return shouldDiveInChildNode && nodeHasTokens(child, sourceFile) ? find(child) : undefined;
});
}
}
/**
* Finds the rightmost token satisfying `token.end <= position`,
* excluding `JsxText` tokens containing only whitespace.
*/
export function findPrecedingToken(position: number, sourceFile: SourceFile, startNode?: Node, excludeJsdoc?: boolean): Node | undefined {
const result = find(startNode || sourceFile);
Debug.assert(!(result && isWhiteSpaceOnlyJsxText(result)));
return result;
function find(n: Node): Node | undefined {
if (isNonWhitespaceToken(n) && n.kind !== SyntaxKind.EndOfFileToken) {
return n;
}
const children = n.getChildren(sourceFile);
const i = binarySearchKey(children, position, (_, i) => i, (middle, _) => {
// This last callback is more of a selector than a comparator -
// `EqualTo` causes the `middle` result to be returned
// `GreaterThan` causes recursion on the left of the middle
// `LessThan` causes recursion on the right of the middle
if (position < children[middle].end) {
// first element whose end position is greater than the input position
if (!children[middle - 1] || position >= children[middle - 1].end) {
return Comparison.EqualTo;
}
return Comparison.GreaterThan;
}
return Comparison.LessThan;
});
if (i >= 0 && children[i]) {
const child = children[i];
// Note that the span of a node's tokens is [node.getStart(...), node.end).
// Given that `position < child.end` and child has constituent tokens, we distinguish these cases:
// 1) `position` precedes `child`'s tokens or `child` has no tokens (ie: in a comment or whitespace preceding `child`):
// we need to find the last token in a previous child.
// 2) `position` is within the same span: we recurse on `child`.
if (position < child.end) {
const start = child.getStart(sourceFile, /*includeJsDoc*/ !excludeJsdoc);
const lookInPreviousChild =
(start >= position) || // cursor in the leading trivia
!nodeHasTokens(child, sourceFile) ||
isWhiteSpaceOnlyJsxText(child);
if (lookInPreviousChild) {
// actual start of the node is past the position - previous token should be at the end of previous child
const candidate = findRightmostChildNodeWithTokens(children, /*exclusiveStartPosition*/ i, sourceFile, n.kind);
return candidate && findRightmostToken(candidate, sourceFile);
}
else {
// candidate should be in this node
return find(child);
}
}
}
Debug.assert(startNode !== undefined || n.kind === SyntaxKind.SourceFile || n.kind === SyntaxKind.EndOfFileToken || isJSDocCommentContainingNode(n));
// Here we know that none of child token nodes embrace the position,
// the only known case is when position is at the end of the file.
// Try to find the rightmost token in the file without filtering.
// Namely we are skipping the check: 'position < node.end'
const candidate = findRightmostChildNodeWithTokens(children, /*exclusiveStartPosition*/ children.length, sourceFile, n.kind);
return candidate && findRightmostToken(candidate, sourceFile);
}
}
function isNonWhitespaceToken(n: Node): boolean {
return isToken(n) && !isWhiteSpaceOnlyJsxText(n);
}
function findRightmostToken(n: Node, sourceFile: SourceFile): Node | undefined {
if (isNonWhitespaceToken(n)) {
return n;
}
const children = n.getChildren(sourceFile);
if (children.length === 0) {
return n;
}
const candidate = findRightmostChildNodeWithTokens(children, /*exclusiveStartPosition*/ children.length, sourceFile, n.kind);
return candidate && findRightmostToken(candidate, sourceFile);
}
/**
* Finds the rightmost child to the left of `children[exclusiveStartPosition]` which is a non-all-whitespace token or has constituent tokens.
*/
function findRightmostChildNodeWithTokens(children: Node[], exclusiveStartPosition: number, sourceFile: SourceFile, parentKind: SyntaxKind): Node | undefined {
for (let i = exclusiveStartPosition - 1; i >= 0; i--) {
const child = children[i];
if (isWhiteSpaceOnlyJsxText(child)) {
if (i === 0 && (parentKind === SyntaxKind.JsxText || parentKind === SyntaxKind.JsxSelfClosingElement)) {
Debug.fail("`JsxText` tokens should not be the first child of `JsxElement | JsxSelfClosingElement`");
}
}
else if (nodeHasTokens(children[i], sourceFile)) {
return children[i];
}
}
}
export function isInString(sourceFile: SourceFile, position: number, previousToken = findPrecedingToken(position, sourceFile)): boolean {
if (previousToken && isStringTextContainingNode(previousToken)) {
const start = previousToken.getStart(sourceFile);
const end = previousToken.getEnd();
// To be "in" one of these literals, the position has to be:
// 1. entirely within the token text.
// 2. at the end position of an unterminated token.
// 3. at the end of a regular expression (due to trailing flags like '/foo/g').
if (start < position && position < end) {
return true;
}
if (position === end) {
return !!(previousToken as LiteralExpression).isUnterminated;
}
}
return false;
}
/**
* returns true if the position is in between the open and close elements of an JSX expression.
*/
export function isInsideJsxElementOrAttribute(sourceFile: SourceFile, position: number) {
const token = getTokenAtPosition(sourceFile, position);
if (!token) {
return false;
}
if (token.kind === SyntaxKind.JsxText) {
return true;
}
// <div>Hello |</div>
if (token.kind === SyntaxKind.LessThanToken && token.parent.kind === SyntaxKind.JsxText) {
return true;
}
// <div> { | </div> or <div a={| </div>
if (token.kind === SyntaxKind.LessThanToken && token.parent.kind === SyntaxKind.JsxExpression) {
return true;
}
// <div> {
// |
// } < /div>
if (token && token.kind === SyntaxKind.CloseBraceToken && token.parent.kind === SyntaxKind.JsxExpression) {
return true;
}
// <div>|</div>
if (token.kind === SyntaxKind.LessThanToken && token.parent.kind === SyntaxKind.JsxClosingElement) {
return true;
}
return false;
}
function isWhiteSpaceOnlyJsxText(node: Node): boolean {
return isJsxText(node) && node.containsOnlyTriviaWhiteSpaces;
}
export function isInTemplateString(sourceFile: SourceFile, position: number) {
const token = getTokenAtPosition(sourceFile, position);
return isTemplateLiteralKind(token.kind) && position > token.getStart(sourceFile);
}
export function isInJSXText(sourceFile: SourceFile, position: number) {
const token = getTokenAtPosition(sourceFile, position);
if (isJsxText(token)) {
return true;
}
if (token.kind === SyntaxKind.OpenBraceToken && isJsxExpression(token.parent) && isJsxElement(token.parent.parent)) {
return true;
}
if (token.kind === SyntaxKind.LessThanToken && isJsxOpeningLikeElement(token.parent) && isJsxElement(token.parent.parent)) {
return true;
}
return false;
}
export function isInsideJsxElement(sourceFile: SourceFile, position: number): boolean {
function isInsideJsxElementTraversal(node: Node): boolean {
while (node) {
if (node.kind >= SyntaxKind.JsxSelfClosingElement && node.kind <= SyntaxKind.JsxExpression
|| node.kind === SyntaxKind.JsxText
|| node.kind === SyntaxKind.LessThanToken
|| node.kind === SyntaxKind.GreaterThanToken
|| node.kind === SyntaxKind.Identifier
|| node.kind === SyntaxKind.CloseBraceToken
|| node.kind === SyntaxKind.OpenBraceToken
|| node.kind === SyntaxKind.SlashToken) {
node = node.parent;
}
else if (node.kind === SyntaxKind.JsxElement) {
if (position > node.getStart(sourceFile)) return true;
node = node.parent;
}
else {
return false;
}
}
return false;
}
return isInsideJsxElementTraversal(getTokenAtPosition(sourceFile, position));
}
export function findPrecedingMatchingToken(token: Node, matchingTokenKind: SyntaxKind.OpenBraceToken | SyntaxKind.OpenParenToken | SyntaxKind.OpenBracketToken, sourceFile: SourceFile) {
const closeTokenText = tokenToString(token.kind)!;
const matchingTokenText = tokenToString(matchingTokenKind)!;
const tokenFullStart = token.getFullStart();
// Text-scan based fast path - can be bamboozled by comments and other trivia, but often provides
// a good, fast approximation without too much extra work in the cases where it fails.
const bestGuessIndex = sourceFile.text.lastIndexOf(matchingTokenText, tokenFullStart);
if (bestGuessIndex === -1) {
return undefined; // if the token text doesn't appear in the file, there can't be a match - super fast bail
}
// we can only use the textual result directly if we didn't have to count any close tokens within the range
if (sourceFile.text.lastIndexOf(closeTokenText, tokenFullStart - 1) < bestGuessIndex) {
const nodeAtGuess = findPrecedingToken(bestGuessIndex + 1, sourceFile);
if (nodeAtGuess && nodeAtGuess.kind === matchingTokenKind) {
return nodeAtGuess;
}
}
const tokenKind = token.kind;
let remainingMatchingTokens = 0;
while (true) {
const preceding = findPrecedingToken(token.getFullStart(), sourceFile);
if (!preceding) {
return undefined;
}
token = preceding;
if (token.kind === matchingTokenKind) {
if (remainingMatchingTokens === 0) {
return token;
}
remainingMatchingTokens--;
}
else if (token.kind === tokenKind) {
remainingMatchingTokens++;
}
}
}
export function removeOptionality(type: Type, isOptionalExpression: boolean, isOptionalChain: boolean) {
return isOptionalExpression ? type.getNonNullableType() :
isOptionalChain ? type.getNonOptionalType() :
type;
}
export function isPossiblyTypeArgumentPosition(token: Node, sourceFile: SourceFile, checker: TypeChecker): boolean {
const info = getPossibleTypeArgumentsInfo(token, sourceFile);
return info !== undefined && (isPartOfTypeNode(info.called) ||
getPossibleGenericSignatures(info.called, info.nTypeArguments, checker).length !== 0 ||
isPossiblyTypeArgumentPosition(info.called, sourceFile, checker));
}
export function getPossibleGenericSignatures(called: Expression, typeArgumentCount: number, checker: TypeChecker): readonly Signature[] {
let type = checker.getTypeAtLocation(called);
if (isOptionalChain(called.parent)) {
type = removeOptionality(type, isOptionalChainRoot(called.parent), /*isOptionalChain*/ true);
}
const signatures = isNewExpression(called.parent) ? type.getConstructSignatures() : type.getCallSignatures();
return signatures.filter(candidate => !!candidate.typeParameters && candidate.typeParameters.length >= typeArgumentCount);
}
export interface PossibleTypeArgumentInfo {
readonly called: Identifier;
readonly nTypeArguments: number;
}
export interface PossibleProgramFileInfo {
ProgramFiles?: string[];
}
// Get info for an expression like `f <` that may be the start of type arguments.
export function getPossibleTypeArgumentsInfo(tokenIn: Node | undefined, sourceFile: SourceFile): PossibleTypeArgumentInfo | undefined {
// This is a rare case, but one that saves on a _lot_ of work if true - if the source file has _no_ `<` character,
// then there obviously can't be any type arguments - no expensive brace-matching backwards scanning required
if (sourceFile.text.lastIndexOf("<", tokenIn ? tokenIn.pos : sourceFile.text.length) === -1) {
return undefined;
}
let token: Node | undefined = tokenIn;
// This function determines if the node could be type argument position
// Since during editing, when type argument list is not complete,
// the tree could be of any shape depending on the tokens parsed before current node,
// scanning of the previous identifier followed by "<" before current node would give us better result
// Note that we also balance out the already provided type arguments, arrays, object literals while doing so
let remainingLessThanTokens = 0;
let nTypeArguments = 0;
while (token) {
switch (token.kind) {
case SyntaxKind.LessThanToken:
// Found the beginning of the generic argument expression
token = findPrecedingToken(token.getFullStart(), sourceFile);
if (token && token.kind === SyntaxKind.QuestionDotToken) {
token = findPrecedingToken(token.getFullStart(), sourceFile);
}
if (!token || !isIdentifier(token)) return undefined;
if (!remainingLessThanTokens) {
return isDeclarationName(token) ? undefined : { called: token, nTypeArguments };
}
remainingLessThanTokens--;
break;
case SyntaxKind.GreaterThanGreaterThanGreaterThanToken:
remainingLessThanTokens = + 3;
break;
case SyntaxKind.GreaterThanGreaterThanToken:
remainingLessThanTokens = + 2;
break;
case SyntaxKind.GreaterThanToken:
remainingLessThanTokens++;
break;
case SyntaxKind.CloseBraceToken:
// This can be object type, skip until we find the matching open brace token
// Skip until the matching open brace token
token = findPrecedingMatchingToken(token, SyntaxKind.OpenBraceToken, sourceFile);
if (!token) return undefined;
break;
case SyntaxKind.CloseParenToken:
// This can be object type, skip until we find the matching open brace token
// Skip until the matching open brace token
token = findPrecedingMatchingToken(token, SyntaxKind.OpenParenToken, sourceFile);
if (!token) return undefined;
break;
case SyntaxKind.CloseBracketToken:
// This can be object type, skip until we find the matching open brace token
// Skip until the matching open brace token
token = findPrecedingMatchingToken(token, SyntaxKind.OpenBracketToken, sourceFile);
if (!token) return undefined;
break;
// Valid tokens in a type name. Skip.
case SyntaxKind.CommaToken:
nTypeArguments++;
break;
case SyntaxKind.EqualsGreaterThanToken:
// falls through
case SyntaxKind.Identifier:
case SyntaxKind.StringLiteral:
case SyntaxKind.NumericLiteral:
case SyntaxKind.BigIntLiteral:
case SyntaxKind.TrueKeyword:
case SyntaxKind.FalseKeyword:
// falls through
case SyntaxKind.TypeOfKeyword:
case SyntaxKind.ExtendsKeyword:
case SyntaxKind.KeyOfKeyword:
case SyntaxKind.DotToken:
case SyntaxKind.BarToken:
case SyntaxKind.QuestionToken:
case SyntaxKind.ColonToken:
break;
default:
if (isTypeNode(token)) {
break;
}
// Invalid token in type
return undefined;
}
token = findPrecedingToken(token.getFullStart(), sourceFile);
}
return undefined;
}
/**
* Returns true if the cursor at position in sourceFile is within a comment.
*
* @param tokenAtPosition Must equal `getTokenAtPosition(sourceFile, position)
* @param predicate Additional predicate to test on the comment range.
*/
export function isInComment(sourceFile: SourceFile, position: number, tokenAtPosition?: Node): CommentRange | undefined {
return formatting.getRangeOfEnclosingComment(sourceFile, position, /*precedingToken*/ undefined, tokenAtPosition);
}
export function hasDocComment(sourceFile: SourceFile, position: number): boolean {
const token = getTokenAtPosition(sourceFile, position);
return !!findAncestor(token, isJSDoc);
}
function nodeHasTokens(n: Node, sourceFile: SourceFileLike): boolean {
// If we have a token or node that has a non-zero width, it must have tokens.
// Note: getWidth() does not take trivia into account.
return n.kind === SyntaxKind.EndOfFileToken ? !!(n as EndOfFileToken).jsDoc : n.getWidth(sourceFile) !== 0;
}
export function getNodeModifiers(node: Node, excludeFlags = ModifierFlags.None): string {
const result: string[] = [];
const flags = isDeclaration(node)
? getCombinedNodeFlagsAlwaysIncludeJSDoc(node) & ~excludeFlags
: ModifierFlags.None;
if (flags & ModifierFlags.Private) result.push(ScriptElementKindModifier.privateMemberModifier);
if (flags & ModifierFlags.Protected) result.push(ScriptElementKindModifier.protectedMemberModifier);
if (flags & ModifierFlags.Public) result.push(ScriptElementKindModifier.publicMemberModifier);
if (flags & ModifierFlags.Static || isClassStaticBlockDeclaration(node)) result.push(ScriptElementKindModifier.staticModifier);
if (flags & ModifierFlags.Abstract) result.push(ScriptElementKindModifier.abstractModifier);
if (flags & ModifierFlags.Export) result.push(ScriptElementKindModifier.exportedModifier);
if (flags & ModifierFlags.Deprecated) result.push(ScriptElementKindModifier.deprecatedModifier);
if (node.flags & NodeFlags.Ambient) result.push(ScriptElementKindModifier.ambientModifier);
if (node.kind === SyntaxKind.ExportAssignment) result.push(ScriptElementKindModifier.exportedModifier);
return result.length > 0 ? result.join(",") : ScriptElementKindModifier.none;
}
export function getTypeArgumentOrTypeParameterList(node: Node): NodeArray<Node> | undefined {
if (node.kind === SyntaxKind.TypeReference || node.kind === SyntaxKind.CallExpression) {
return (node as CallExpression).typeArguments;
}
if (isFunctionLike(node) || node.kind === SyntaxKind.ClassDeclaration || node.kind === SyntaxKind.InterfaceDeclaration) {
return (node as FunctionLikeDeclaration).typeParameters;
}
return undefined;
}
export function isComment(kind: SyntaxKind): boolean {
return kind === SyntaxKind.SingleLineCommentTrivia || kind === SyntaxKind.MultiLineCommentTrivia;
}
export function isStringOrRegularExpressionOrTemplateLiteral(kind: SyntaxKind): boolean {
if (kind === SyntaxKind.StringLiteral
|| kind === SyntaxKind.RegularExpressionLiteral
|| isTemplateLiteralKind(kind)) {
return true;
}
return false;
}
export function isPunctuation(kind: SyntaxKind): boolean {
return SyntaxKind.FirstPunctuation <= kind && kind <= SyntaxKind.LastPunctuation;
}
export function isInsideTemplateLiteral(node: TemplateLiteralToken, position: number, sourceFile: SourceFile): boolean {
return isTemplateLiteralKind(node.kind)
&& (node.getStart(sourceFile) < position && position < node.end) || (!!node.isUnterminated && position === node.end);
}
export function isAccessibilityModifier(kind: SyntaxKind) {
switch (kind) {
case SyntaxKind.PublicKeyword:
case SyntaxKind.PrivateKeyword:
case SyntaxKind.ProtectedKeyword:
return true;
}
return false;
}
export function cloneCompilerOptions(options: CompilerOptions): CompilerOptions {
const result = clone(options);
setConfigFileInOptions(result, options && options.configFile);
return result;
}
export function isArrayLiteralOrObjectLiteralDestructuringPattern(node: Node) {
if (node.kind === SyntaxKind.ArrayLiteralExpression ||
node.kind === SyntaxKind.ObjectLiteralExpression) {
// [a,b,c] from:
// [a, b, c] = someExpression;
if (node.parent.kind === SyntaxKind.BinaryExpression &&
(node.parent as BinaryExpression).left === node &&
(node.parent as BinaryExpression).operatorToken.kind === SyntaxKind.EqualsToken) {
return true;
}
// [a, b, c] from:
// for([a, b, c] of expression)
if (node.parent.kind === SyntaxKind.ForOfStatement &&
(node.parent as ForOfStatement).initializer === node) {
return true;
}
// [a, b, c] of
// [x, [a, b, c] ] = someExpression
// or
// {x, a: {a, b, c} } = someExpression
if (isArrayLiteralOrObjectLiteralDestructuringPattern(node.parent.kind === SyntaxKind.PropertyAssignment ? node.parent.parent : node.parent)) {
return true;
}
}
return false;
}
export function isInReferenceComment(sourceFile: SourceFile, position: number): boolean {
return isInReferenceCommentWorker(sourceFile, position, /*shouldBeReference*/ true);
}
export function isInNonReferenceComment(sourceFile: SourceFile, position: number): boolean {
return isInReferenceCommentWorker(sourceFile, position, /*shouldBeReference*/ false);
}
function isInReferenceCommentWorker(sourceFile: SourceFile, position: number, shouldBeReference: boolean): boolean {
const range = isInComment(sourceFile, position, /*tokenAtPosition*/ undefined);
return !!range && shouldBeReference === tripleSlashDirectivePrefixRegex.test(sourceFile.text.substring(range.pos, range.end));
}
export function getReplacementSpanForContextToken(contextToken: Node | undefined) {
if (!contextToken) return undefined;
switch (contextToken.kind) {
case SyntaxKind.StringLiteral:
case SyntaxKind.NoSubstitutionTemplateLiteral:
return createTextSpanFromStringLiteralLikeContent(contextToken as StringLiteralLike);
default:
return createTextSpanFromNode(contextToken);
}
}
export function createTextSpanFromNode(node: Node, sourceFile?: SourceFile, endNode?: Node): TextSpan {
return createTextSpanFromBounds(node.getStart(sourceFile), (endNode || node).getEnd());
}
export function createTextSpanFromStringLiteralLikeContent(node: StringLiteralLike) {
if (node.isUnterminated) return undefined;
return createTextSpanFromBounds(node.getStart() + 1, node.getEnd() - 1);
}
export function createTextRangeFromNode(node: Node, sourceFile: SourceFile): TextRange {
return createRange(node.getStart(sourceFile), node.end);
}
export function createTextSpanFromRange(range: TextRange): TextSpan {
return createTextSpanFromBounds(range.pos, range.end);
}
export function createTextRangeFromSpan(span: TextSpan): TextRange {
return createRange(span.start, span.start + span.length);
}
export function createTextChangeFromStartLength(start: number, length: number, newText: string): TextChange {
return createTextChange(createTextSpan(start, length), newText);
}
export function createTextChange(span: TextSpan, newText: string): TextChange {
return { span, newText };
}
export const typeKeywords: readonly SyntaxKind[] = [
SyntaxKind.AnyKeyword,
SyntaxKind.AssertsKeyword,
SyntaxKind.BigIntKeyword,
SyntaxKind.BooleanKeyword,
SyntaxKind.FalseKeyword,
SyntaxKind.InferKeyword,
SyntaxKind.KeyOfKeyword,
SyntaxKind.NeverKeyword,
SyntaxKind.NullKeyword,
SyntaxKind.NumberKeyword,
SyntaxKind.ObjectKeyword,
SyntaxKind.ReadonlyKeyword,
SyntaxKind.StringKeyword,
SyntaxKind.SymbolKeyword,
SyntaxKind.TrueKeyword,
SyntaxKind.VoidKeyword,
SyntaxKind.UndefinedKeyword,
SyntaxKind.UniqueKeyword,
SyntaxKind.UnknownKeyword,
];
export function isTypeKeyword(kind: SyntaxKind): boolean {
return contains(typeKeywords, kind);
}
export function isTypeKeywordToken(node: Node): node is Token<SyntaxKind.TypeKeyword> {
return node.kind === SyntaxKind.TypeKeyword;
}
export function isTypeKeywordTokenOrIdentifier(node: Node) {
return isTypeKeywordToken(node) || isIdentifier(node) && node.text === "type";
}
/** True if the symbol is for an external module, as opposed to a namespace. */
export function isExternalModuleSymbol(moduleSymbol: Symbol): boolean {
return !!(moduleSymbol.flags & SymbolFlags.Module) && moduleSymbol.name.charCodeAt(0) === CharacterCodes.doubleQuote;
}
/** Returns `true` the first time it encounters a node and `false` afterwards. */
export type NodeSeenTracker<T = Node> = (node: T) => boolean;
export function nodeSeenTracker<T extends Node>(): NodeSeenTracker<T> {
const seen: true[] = [];
return node => {
const id = getNodeId(node);
return !seen[id] && (seen[id] = true);
};
}
export function getSnapshotText(snap: IScriptSnapshot): string {
return snap.getText(0, snap.getLength());
}
export function repeatString(str: string, count: number): string {
let result = "";
for (let i = 0; i < count; i++) {
result += str;
}
return result;
}
export function skipConstraint(type: Type): Type {
return type.isTypeParameter() ? type.getConstraint() || type : type;
}
export function getNameFromPropertyName(name: PropertyName): string | undefined {
return name.kind === SyntaxKind.ComputedPropertyName
// treat computed property names where expression is string/numeric literal as just string/numeric literal
? isStringOrNumericLiteralLike(name.expression) ? name.expression.text : undefined
: isPrivateIdentifier(name) ? idText(name) : getTextOfIdentifierOrLiteral(name);
}
export function programContainsModules(program: Program): boolean {
return program.getSourceFiles().some(s => !s.isDeclarationFile && !program.isSourceFileFromExternalLibrary(s) && !!(s.externalModuleIndicator || s.commonJsModuleIndicator));
}
export function programContainsEsModules(program: Program): boolean {
return program.getSourceFiles().some(s => !s.isDeclarationFile && !program.isSourceFileFromExternalLibrary(s) && !!s.externalModuleIndicator);
}
export function compilerOptionsIndicateEsModules(compilerOptions: CompilerOptions): boolean {
return !!compilerOptions.module || getEmitScriptTarget(compilerOptions) >= ScriptTarget.ES2015 || !!compilerOptions.noEmit;
}
export function createModuleSpecifierResolutionHost(program: Program, host: LanguageServiceHost): ModuleSpecifierResolutionHost {
// Mix in `getSymlinkCache` from Program when host doesn't have it
// in order for non-Project hosts to have a symlinks cache.
return {
fileExists: fileName => program.fileExists(fileName),
getCurrentDirectory: () => host.getCurrentDirectory(),
readFile: maybeBind(host, host.readFile),
useCaseSensitiveFileNames: maybeBind(host, host.useCaseSensitiveFileNames),
getSymlinkCache: maybeBind(host, host.getSymlinkCache) || program.getSymlinkCache,
getModuleSpecifierCache: maybeBind(host, host.getModuleSpecifierCache),
getPackageJsonInfoCache: () => program.getModuleResolutionCache()?.getPackageJsonInfoCache(),
getGlobalTypingsCacheLocation: maybeBind(host, host.getGlobalTypingsCacheLocation),
redirectTargetsMap: program.redirectTargetsMap,
getProjectReferenceRedirect: fileName => program.getProjectReferenceRedirect(fileName),
isSourceOfProjectReferenceRedirect: fileName => program.isSourceOfProjectReferenceRedirect(fileName),
getNearestAncestorDirectoryWithPackageJson: maybeBind(host, host.getNearestAncestorDirectoryWithPackageJson),
getFileIncludeReasons: () => program.getFileIncludeReasons(),
};
}
export function getModuleSpecifierResolverHost(program: Program, host: LanguageServiceHost): SymbolTracker["moduleResolverHost"] {
return {
...createModuleSpecifierResolutionHost(program, host),
getCommonSourceDirectory: () => program.getCommonSourceDirectory(),
};
}
export function makeImportIfNecessary(defaultImport: Identifier | undefined, namedImports: readonly ImportSpecifier[] | undefined, moduleSpecifier: string, quotePreference: QuotePreference): ImportDeclaration | undefined {
return defaultImport || namedImports && namedImports.length ? makeImport(defaultImport, namedImports, moduleSpecifier, quotePreference) : undefined;
}
export function makeImport(defaultImport: Identifier | undefined, namedImports: readonly ImportSpecifier[] | undefined, moduleSpecifier: string | Expression, quotePreference: QuotePreference, isTypeOnly?: boolean): ImportDeclaration {
return factory.createImportDeclaration(
/*decorators*/ undefined,
/*modifiers*/ undefined,
defaultImport || namedImports
? factory.createImportClause(!!isTypeOnly, defaultImport, namedImports && namedImports.length ? factory.createNamedImports(namedImports) : undefined)
: undefined,
typeof moduleSpecifier === "string" ? makeStringLiteral(moduleSpecifier, quotePreference) : moduleSpecifier,
/*assertClause*/ undefined);
}
export function makeStringLiteral(text: string, quotePreference: QuotePreference): StringLiteral {
return factory.createStringLiteral(text, quotePreference === QuotePreference.Single);
}
export const enum QuotePreference { Single, Double }
export function quotePreferenceFromString(str: StringLiteral, sourceFile: SourceFile): QuotePreference {
return isStringDoubleQuoted(str, sourceFile) ? QuotePreference.Double : QuotePreference.Single;
}
export function getQuotePreference(sourceFile: SourceFile, preferences: UserPreferences): QuotePreference {
if (preferences.quotePreference && preferences.quotePreference !== "auto") {
return preferences.quotePreference === "single" ? QuotePreference.Single : QuotePreference.Double;
}
else {
// ignore synthetic import added when importHelpers: true
const firstModuleSpecifier = sourceFile.imports &&
find(sourceFile.imports, n => isStringLiteral(n) && !nodeIsSynthesized(n.parent)) as StringLiteral;
return firstModuleSpecifier ? quotePreferenceFromString(firstModuleSpecifier, sourceFile) : QuotePreference.Double;
}
}
export function getQuoteFromPreference(qp: QuotePreference): string {
switch (qp) {
case QuotePreference.Single: return "'";
case QuotePreference.Double: return '"';
default: return Debug.assertNever(qp);
}
}
export function symbolNameNoDefault(symbol: Symbol): string | undefined {
const escaped = symbolEscapedNameNoDefault(symbol);
return escaped === undefined ? undefined : unescapeLeadingUnderscores(escaped);
}
export function symbolEscapedNameNoDefault(symbol: Symbol): __String | undefined {
if (symbol.escapedName !== InternalSymbolName.Default) {
return symbol.escapedName;
}
return firstDefined(symbol.declarations, decl => {
const name = getNameOfDeclaration(decl);
return name && name.kind === SyntaxKind.Identifier ? name.escapedText : undefined;
});
}
export function isModuleSpecifierLike(node: Node): node is StringLiteralLike {
return isStringLiteralLike(node) && (
isExternalModuleReference(node.parent) ||
isImportDeclaration(node.parent) ||
isRequireCall(node.parent, /*requireStringLiteralLikeArgument*/ false) && node.parent.arguments[0] === node ||
isImportCall(node.parent) && node.parent.arguments[0] === node);
}
export type ObjectBindingElementWithoutPropertyName = BindingElement & { name: Identifier };
export function isObjectBindingElementWithoutPropertyName(bindingElement: Node): bindingElement is ObjectBindingElementWithoutPropertyName {
return isBindingElement(bindingElement) &&
isObjectBindingPattern(bindingElement.parent) &&
isIdentifier(bindingElement.name) &&
!bindingElement.propertyName;
}
export function getPropertySymbolFromBindingElement(checker: TypeChecker, bindingElement: ObjectBindingElementWithoutPropertyName): Symbol | undefined {
const typeOfPattern = checker.getTypeAtLocation(bindingElement.parent);
return typeOfPattern && checker.getPropertyOfType(typeOfPattern, bindingElement.name.text);
}
export function getParentNodeInSpan(node: Node | undefined, file: SourceFile, span: TextSpan): Node | undefined {
if (!node) return undefined;
while (node.parent) {
if (isSourceFile(node.parent) || !spanContainsNode(span, node.parent, file)) {
return node;
}
node = node.parent;
}
}
function spanContainsNode(span: TextSpan, node: Node, file: SourceFile): boolean {
return textSpanContainsPosition(span, node.getStart(file)) &&
node.getEnd() <= textSpanEnd(span);
}
export function findModifier(node: Node, kind: Modifier["kind"]): Modifier | undefined {
return node.modifiers && find(node.modifiers, m => m.kind === kind);
}
export function insertImports(changes: textChanges.ChangeTracker, sourceFile: SourceFile, imports: AnyImportOrRequireStatement | readonly AnyImportOrRequireStatement[], blankLineBetween: boolean): void {
const decl = isArray(imports) ? imports[0] : imports;
const importKindPredicate: (node: Node) => node is AnyImportOrRequireStatement = decl.kind === SyntaxKind.VariableStatement ? isRequireVariableStatement : isAnyImportSyntax;
const existingImportStatements = filter(sourceFile.statements, importKindPredicate);
const sortedNewImports = isArray(imports) ? stableSort(imports, OrganizeImports.compareImportsOrRequireStatements) : [imports];
if (!existingImportStatements.length) {
changes.insertNodesAtTopOfFile(sourceFile, sortedNewImports, blankLineBetween);
}
else if (existingImportStatements && OrganizeImports.importsAreSorted(existingImportStatements)) {
for (const newImport of sortedNewImports) {
const insertionIndex = OrganizeImports.getImportDeclarationInsertionIndex(existingImportStatements, newImport);
if (insertionIndex === 0) {
// If the first import is top-of-file, insert after the leading comment which is likely the header.
const options = existingImportStatements[0] === sourceFile.statements[0] ?
{ leadingTriviaOption: textChanges.LeadingTriviaOption.Exclude } : {};
changes.insertNodeBefore(sourceFile, existingImportStatements[0], newImport, /*blankLineBetween*/ false, options);
}
else {
const prevImport = existingImportStatements[insertionIndex - 1];
changes.insertNodeAfter(sourceFile, prevImport, newImport);
}
}
}
else {
const lastExistingImport = lastOrUndefined(existingImportStatements);
if (lastExistingImport) {
changes.insertNodesAfter(sourceFile, lastExistingImport, sortedNewImports);
}
else {
changes.insertNodesAtTopOfFile(sourceFile, sortedNewImports, blankLineBetween);
}
}
}
export function getTypeKeywordOfTypeOnlyImport(importClause: ImportClause, sourceFile: SourceFile): Token<SyntaxKind.TypeKeyword> {
Debug.assert(importClause.isTypeOnly);
return cast(importClause.getChildAt(0, sourceFile), isTypeKeywordToken);
}
export function textSpansEqual(a: TextSpan | undefined, b: TextSpan | undefined): boolean {
return !!a && !!b && a.start === b.start && a.length === b.length;
}
export function documentSpansEqual(a: DocumentSpan, b: DocumentSpan): boolean {
return a.fileName === b.fileName && textSpansEqual(a.textSpan, b.textSpan);
}
/**
* Iterates through 'array' by index and performs the callback on each element of array until the callback
* returns a truthy value, then returns that value.
* If no such value is found, the callback is applied to each element of array and undefined is returned.
*/
export function forEachUnique<T, U>(array: readonly T[] | undefined, callback: (element: T, index: number) => U): U | undefined {
if (array) {
for (let i = 0; i < array.length; i++) {
if (array.indexOf(array[i]) === i) {
const result = callback(array[i], i);
if (result) {
return result;
}
}
}
}
return undefined;
}
export function isTextWhiteSpaceLike(text: string, startPos: number, endPos: number): boolean {
for (let i = startPos; i < endPos; i++) {
if (!isWhiteSpaceLike(text.charCodeAt(i))) {
return false;
}
}
return true;
}
// #endregion
// Display-part writer helpers
// #region
export function isFirstDeclarationOfSymbolParameter(symbol: Symbol) {
const declaration = symbol.declarations ? firstOrUndefined(symbol.declarations) : undefined;
return !!findAncestor(declaration, n =>
isParameter(n) ? true : isBindingElement(n) || isObjectBindingPattern(n) || isArrayBindingPattern(n) ? false : "quit");
}
const displayPartWriter = getDisplayPartWriter();
function getDisplayPartWriter(): DisplayPartsSymbolWriter {
const absoluteMaximumLength = defaultMaximumTruncationLength * 10; // A hard cutoff to avoid overloading the messaging channel in worst-case scenarios
let displayParts: SymbolDisplayPart[];
let lineStart: boolean;
let indent: number;
let length: number;
resetWriter();
const unknownWrite = (text: string) => writeKind(text, SymbolDisplayPartKind.text);
return {
displayParts: () => {
const finalText = displayParts.length && displayParts[displayParts.length - 1].text;
if (length > absoluteMaximumLength && finalText && finalText !== "...") {
if (!isWhiteSpaceLike(finalText.charCodeAt(finalText.length - 1))) {
displayParts.push(displayPart(" ", SymbolDisplayPartKind.space));
}
displayParts.push(displayPart("...", SymbolDisplayPartKind.punctuation));
}
return displayParts;
},
writeKeyword: text => writeKind(text, SymbolDisplayPartKind.keyword),
writeOperator: text => writeKind(text, SymbolDisplayPartKind.operator),
writePunctuation: text => writeKind(text, SymbolDisplayPartKind.punctuation),
writeTrailingSemicolon: text => writeKind(text, SymbolDisplayPartKind.punctuation),
writeSpace: text => writeKind(text, SymbolDisplayPartKind.space),
writeStringLiteral: text => writeKind(text, SymbolDisplayPartKind.stringLiteral),
writeParameter: text => writeKind(text, SymbolDisplayPartKind.parameterName),
writeProperty: text => writeKind(text, SymbolDisplayPartKind.propertyName),
writeLiteral: text => writeKind(text, SymbolDisplayPartKind.stringLiteral),
writeSymbol,
writeLine,
write: unknownWrite,
writeComment: unknownWrite,
getText: () => "",
getTextPos: () => 0,
getColumn: () => 0,
getLine: () => 0,
isAtStartOfLine: () => false,
hasTrailingWhitespace: () => false,
hasTrailingComment: () => false,
rawWrite: notImplemented,
getIndent: () => indent,
increaseIndent: () => { indent++; },
decreaseIndent: () => { indent--; },
clear: resetWriter,
trackSymbol: () => false,
reportInaccessibleThisError: noop,
reportInaccessibleUniqueSymbolError: noop,
reportPrivateInBaseOfClassExpression: noop,
};
function writeIndent() {
if (length > absoluteMaximumLength) return;
if (lineStart) {
const indentString = getIndentString(indent);
if (indentString) {
length += indentString.length;
displayParts.push(displayPart(indentString, SymbolDisplayPartKind.space));
}
lineStart = false;
}
}
function writeKind(text: string, kind: SymbolDisplayPartKind) {
if (length > absoluteMaximumLength) return;
writeIndent();
length += text.length;
displayParts.push(displayPart(text, kind));
}
function writeSymbol(text: string, symbol: Symbol) {
if (length > absoluteMaximumLength) return;
writeIndent();
length += text.length;
displayParts.push(symbolPart(text, symbol));
}
function writeLine() {
if (length > absoluteMaximumLength) return;
length += 1;
displayParts.push(lineBreakPart());
lineStart = true;
}
function resetWriter() {
displayParts = [];
lineStart = true;
indent = 0;
length = 0;
}
}
export function symbolPart(text: string, symbol: Symbol) {
return displayPart(text, displayPartKind(symbol));
function displayPartKind(symbol: Symbol): SymbolDisplayPartKind {
const flags = symbol.flags;
if (flags & SymbolFlags.Variable) {
return isFirstDeclarationOfSymbolParameter(symbol) ? SymbolDisplayPartKind.parameterName : SymbolDisplayPartKind.localName;
}
if (flags & SymbolFlags.Property) return SymbolDisplayPartKind.propertyName;
if (flags & SymbolFlags.GetAccessor) return SymbolDisplayPartKind.propertyName;
if (flags & SymbolFlags.SetAccessor) return SymbolDisplayPartKind.propertyName;
if (flags & SymbolFlags.EnumMember) return SymbolDisplayPartKind.enumMemberName;
if (flags & SymbolFlags.Function) return SymbolDisplayPartKind.functionName;
if (flags & SymbolFlags.Class) return SymbolDisplayPartKind.className;
if (flags & SymbolFlags.Interface) return SymbolDisplayPartKind.interfaceName;
if (flags & SymbolFlags.Enum) return SymbolDisplayPartKind.enumName;
if (flags & SymbolFlags.Module) return SymbolDisplayPartKind.moduleName;
if (flags & SymbolFlags.Method) return SymbolDisplayPartKind.methodName;
if (flags & SymbolFlags.TypeParameter) return SymbolDisplayPartKind.typeParameterName;
if (flags & SymbolFlags.TypeAlias) return SymbolDisplayPartKind.aliasName;
if (flags & SymbolFlags.Alias) return SymbolDisplayPartKind.aliasName;
return SymbolDisplayPartKind.text;
}
}
export function displayPart(text: string, kind: SymbolDisplayPartKind): SymbolDisplayPart {
return { text, kind: SymbolDisplayPartKind[kind] };
}
export function spacePart() {
return displayPart(" ", SymbolDisplayPartKind.space);
}
export function keywordPart(kind: SyntaxKind) {
return displayPart(tokenToString(kind)!, SymbolDisplayPartKind.keyword);
}
export function punctuationPart(kind: SyntaxKind) {
return displayPart(tokenToString(kind)!, SymbolDisplayPartKind.punctuation);
}
export function operatorPart(kind: SyntaxKind) {
return displayPart(tokenToString(kind)!, SymbolDisplayPartKind.operator);
}
export function parameterNamePart(text: string) {
return displayPart(text, SymbolDisplayPartKind.parameterName);
}
export function propertyNamePart(text: string) {
return displayPart(text, SymbolDisplayPartKind.propertyName);
}
export function textOrKeywordPart(text: string) {
const kind = stringToToken(text);
return kind === undefined
? textPart(text)
: keywordPart(kind);
}
export function textPart(text: string) {
return displayPart(text, SymbolDisplayPartKind.text);
}
export function typeAliasNamePart(text: string) {
return displayPart(text, SymbolDisplayPartKind.aliasName);
}
export function typeParameterNamePart(text: string) {
return displayPart(text, SymbolDisplayPartKind.typeParameterName);
}
export function linkTextPart(text: string) {
return displayPart(text, SymbolDisplayPartKind.linkText);
}
export function linkNamePart(text: string, target: Declaration): JSDocLinkDisplayPart {
return {
text,
kind: SymbolDisplayPartKind[SymbolDisplayPartKind.linkName],
target: {
fileName: getSourceFileOfNode(target).fileName,
textSpan: createTextSpanFromNode(target),
},
};
}
export function linkPart(text: string) {
return displayPart(text, SymbolDisplayPartKind.link);
}
export function buildLinkParts(link: JSDocLink | JSDocLinkCode | JSDocLinkPlain, checker?: TypeChecker): SymbolDisplayPart[] {
const prefix = isJSDocLink(link) ? "link"
: isJSDocLinkCode(link) ? "linkcode"
: "linkplain";
const parts = [linkPart(`{@${prefix} `)];
if (!link.name) {
if (link.text) parts.push(linkTextPart(link.text));
}
else {
const symbol = checker?.getSymbolAtLocation(link.name);
const suffix = findLinkNameEnd(link.text);
const name = getTextOfNode(link.name) + link.text.slice(0, suffix);
const text = link.text.slice(suffix);
const decl = symbol?.valueDeclaration || symbol?.declarations?.[0];
if (decl) {
parts.push(linkNamePart(name, decl));
if (text) parts.push(linkTextPart(text));
}
else {
parts.push(linkTextPart(name + (suffix ? "" : " ") + text));
}
}
parts.push(linkPart("}"));
return parts;
}
function findLinkNameEnd(text: string) {
if (text.indexOf("()") === 0) return 2;
if (text[0] !== "<") return 0;
let brackets = 0;
let i = 0;
while (i < text.length) {
if (text[i] === "<") brackets++;
if (text[i] === ">") brackets--;
i++;
if (!brackets) return i;
}
return 0;
}
const carriageReturnLineFeed = "\r\n";
/**
* The default is CRLF.
*/
export function getNewLineOrDefaultFromHost(host: FormattingHost, formatSettings?: FormatCodeSettings) {
return formatSettings?.newLineCharacter ||
host.getNewLine?.() ||
carriageReturnLineFeed;
}
export function lineBreakPart() {
return displayPart("\n", SymbolDisplayPartKind.lineBreak);
}
export function mapToDisplayParts(writeDisplayParts: (writer: DisplayPartsSymbolWriter) => void): SymbolDisplayPart[] {
try {
writeDisplayParts(displayPartWriter);
return displayPartWriter.displayParts();
}
finally {
displayPartWriter.clear();
}
}
export function typeToDisplayParts(typechecker: TypeChecker, type: Type, enclosingDeclaration?: Node, flags: TypeFormatFlags = TypeFormatFlags.None): SymbolDisplayPart[] {
return mapToDisplayParts(writer => {
typechecker.writeType(type, enclosingDeclaration, flags | TypeFormatFlags.MultilineObjectLiterals | TypeFormatFlags.UseAliasDefinedOutsideCurrentScope, writer);
});
}
export function symbolToDisplayParts(typeChecker: TypeChecker, symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags, flags: SymbolFormatFlags = SymbolFormatFlags.None): SymbolDisplayPart[] {
return mapToDisplayParts(writer => {
typeChecker.writeSymbol(symbol, enclosingDeclaration, meaning, flags | SymbolFormatFlags.UseAliasDefinedOutsideCurrentScope, writer);
});
}
export function signatureToDisplayParts(typechecker: TypeChecker, signature: Signature, enclosingDeclaration?: Node, flags: TypeFormatFlags = TypeFormatFlags.None): SymbolDisplayPart[] {
flags |= TypeFormatFlags.UseAliasDefinedOutsideCurrentScope | TypeFormatFlags.MultilineObjectLiterals | TypeFormatFlags.WriteTypeArgumentsOfSignature | TypeFormatFlags.OmitParameterModifiers;
return mapToDisplayParts(writer => {
typechecker.writeSignature(signature, enclosingDeclaration, flags, /*signatureKind*/ undefined, writer);
});
}
export function isImportOrExportSpecifierName(location: Node): location is Identifier {
return !!location.parent && isImportOrExportSpecifier(location.parent) && location.parent.propertyName === location;
}
export function getScriptKind(fileName: string, host: LanguageServiceHost): ScriptKind {
// First check to see if the script kind was specified by the host. Chances are the host
// may override the default script kind for the file extension.
return ensureScriptKind(fileName, host.getScriptKind && host.getScriptKind(fileName));
}
export function getSymbolTarget(symbol: Symbol, checker: TypeChecker): Symbol {
let next: Symbol = symbol;
while (isAliasSymbol(next) || (isTransientSymbol(next) && next.target)) {
if (isTransientSymbol(next) && next.target) {
next = next.target;
}
else {
next = skipAlias(next, checker);
}
}
return next;
}
function isTransientSymbol(symbol: Symbol): symbol is TransientSymbol {
return (symbol.flags & SymbolFlags.Transient) !== 0;
}
function isAliasSymbol(symbol: Symbol): boolean {
return (symbol.flags & SymbolFlags.Alias) !== 0;
}
export function getUniqueSymbolId(symbol: Symbol, checker: TypeChecker) {
return getSymbolId(skipAlias(symbol, checker));
}
export function getFirstNonSpaceCharacterPosition(text: string, position: number) {
while (isWhiteSpaceLike(text.charCodeAt(position))) {
position += 1;
}
return position;
}
export function getPrecedingNonSpaceCharacterPosition(text: string, position: number) {
while (position > -1 && isWhiteSpaceSingleLine(text.charCodeAt(position))) {
position -= 1;
}
return position + 1;
}
/**
* Creates a deep, memberwise clone of a node with no source map location.
*
* WARNING: This is an expensive operation and is only intended to be used in refactorings
* and code fixes (because those are triggered by explicit user actions).
*/
export function getSynthesizedDeepClone<T extends Node | undefined>(node: T, includeTrivia = true): T {
const clone = node && getSynthesizedDeepCloneWorker(node as NonNullable<T>);
if (clone && !includeTrivia) suppressLeadingAndTrailingTrivia(clone);
return clone;
}
export function getSynthesizedDeepCloneWithReplacements<T extends Node>(
node: T,
includeTrivia: boolean,
replaceNode: (node: Node) => Node | undefined
): T {
let clone = replaceNode(node);
if (clone) {
setOriginalNode(clone, node);
}
else {
clone = getSynthesizedDeepCloneWorker(node as NonNullable<T>, replaceNode);
}
if (clone && !includeTrivia) suppressLeadingAndTrailingTrivia(clone);
return clone as T;
}
function getSynthesizedDeepCloneWorker<T extends Node>(node: T, replaceNode?: (node: Node) => Node | undefined): T {
const nodeClone: (n: T) => T = replaceNode
? n => getSynthesizedDeepCloneWithReplacements(n, /*includeTrivia*/ true, replaceNode)
: getSynthesizedDeepClone;
const nodesClone: (ns: NodeArray<T>) => NodeArray<T> = replaceNode
? ns => ns && getSynthesizedDeepClonesWithReplacements(ns, /*includeTrivia*/ true, replaceNode)
: ns => ns && getSynthesizedDeepClones(ns);
const visited =
visitEachChild(node, nodeClone, nullTransformationContext, nodesClone, nodeClone);
if (visited === node) {
// This only happens for leaf nodes - internal nodes always see their children change.
const clone =
isStringLiteral(node) ? setOriginalNode(factory.createStringLiteralFromNode(node), node) as Node as T :
isNumericLiteral(node) ? setOriginalNode(factory.createNumericLiteral(node.text, node.numericLiteralFlags), node) as Node as T :
factory.cloneNode(node);
return setTextRange(clone, node);
}
// PERF: As an optimization, rather than calling factory.cloneNode, we'll update
// the new node created by visitEachChild with the extra changes factory.cloneNode
// would have made.
(visited as Mutable<T>).parent = undefined!;
return visited;
}
export function getSynthesizedDeepClones<T extends Node>(nodes: NodeArray<T>, includeTrivia?: boolean): NodeArray<T>;
export function getSynthesizedDeepClones<T extends Node>(nodes: NodeArray<T> | undefined, includeTrivia?: boolean): NodeArray<T> | undefined;
export function getSynthesizedDeepClones<T extends Node>(nodes: NodeArray<T> | undefined, includeTrivia = true): NodeArray<T> | undefined {
return nodes && factory.createNodeArray(nodes.map(n => getSynthesizedDeepClone(n, includeTrivia)), nodes.hasTrailingComma);
}
export function getSynthesizedDeepClonesWithReplacements<T extends Node>(
nodes: NodeArray<T>,
includeTrivia: boolean,
replaceNode: (node: Node) => Node | undefined
): NodeArray<T> {
return factory.createNodeArray(nodes.map(n => getSynthesizedDeepCloneWithReplacements(n, includeTrivia, replaceNode)), nodes.hasTrailingComma);
}
/**
* Sets EmitFlags to suppress leading and trailing trivia on the node.
*/
export function suppressLeadingAndTrailingTrivia(node: Node) {
suppressLeadingTrivia(node);
suppressTrailingTrivia(node);
}
/**
* Sets EmitFlags to suppress leading trivia on the node.
*/
export function suppressLeadingTrivia(node: Node) {
addEmitFlagsRecursively(node, EmitFlags.NoLeadingComments, getFirstChild);
}
/**
* Sets EmitFlags to suppress trailing trivia on the node.
*/
export function suppressTrailingTrivia(node: Node) {
addEmitFlagsRecursively(node, EmitFlags.NoTrailingComments, getLastChild);
}
export function copyComments(sourceNode: Node, targetNode: Node) {
const sourceFile = sourceNode.getSourceFile();
const text = sourceFile.text;
if (hasLeadingLineBreak(sourceNode, text)) {
copyLeadingComments(sourceNode, targetNode, sourceFile);
}
else {
copyTrailingAsLeadingComments(sourceNode, targetNode, sourceFile);
}
copyTrailingComments(sourceNode, targetNode, sourceFile);
}
function hasLeadingLineBreak(node: Node, text: string) {
const start = node.getFullStart();
const end = node.getStart();
for (let i = start; i < end; i++) {
if (text.charCodeAt(i) === CharacterCodes.lineFeed) return true;
}
return false;
}
function addEmitFlagsRecursively(node: Node, flag: EmitFlags, getChild: (n: Node) => Node | undefined) {
addEmitFlags(node, flag);
const child = getChild(node);
if (child) addEmitFlagsRecursively(child, flag, getChild);
}
function getFirstChild(node: Node): Node | undefined {
return node.forEachChild(child => child);
}
export function getUniqueName(baseName: string, sourceFile: SourceFile): string {
let nameText = baseName;
for (let i = 1; !isFileLevelUniqueName(sourceFile, nameText); i++) {
nameText = `${baseName}_${i}`;
}
return nameText;
}
/**
* @return The index of the (only) reference to the extracted symbol. We want the cursor
* to be on the reference, rather than the declaration, because it's closer to where the
* user was before extracting it.
*/
export function getRenameLocation(edits: readonly FileTextChanges[], renameFilename: string, name: string, preferLastLocation: boolean): number {
let delta = 0;
let lastPos = -1;
for (const { fileName, textChanges } of edits) {
Debug.assert(fileName === renameFilename);
for (const change of textChanges) {
const { span, newText } = change;
const index = indexInTextChange(newText, name);
if (index !== -1) {
lastPos = span.start + delta + index;
// If the reference comes first, return immediately.
if (!preferLastLocation) {
return lastPos;
}
}
delta += newText.length - span.length;
}
}
// If the declaration comes first, return the position of the last occurrence.
Debug.assert(preferLastLocation);
Debug.assert(lastPos >= 0);
return lastPos;
}
export function copyLeadingComments(sourceNode: Node, targetNode: Node, sourceFile: SourceFile, commentKind?: CommentKind, hasTrailingNewLine?: boolean) {
forEachLeadingCommentRange(sourceFile.text, sourceNode.pos, getAddCommentsFunction(targetNode, sourceFile, commentKind, hasTrailingNewLine, addSyntheticLeadingComment));
}
export function copyTrailingComments(sourceNode: Node, targetNode: Node, sourceFile: SourceFile, commentKind?: CommentKind, hasTrailingNewLine?: boolean) {
forEachTrailingCommentRange(sourceFile.text, sourceNode.end, getAddCommentsFunction(targetNode, sourceFile, commentKind, hasTrailingNewLine, addSyntheticTrailingComment));
}
/**
* This function copies the trailing comments for the token that comes before `sourceNode`, as leading comments of `targetNode`.
* This is useful because sometimes a comment that refers to `sourceNode` will be a leading comment for `sourceNode`, according to the
* notion of trivia ownership, and instead will be a trailing comment for the token before `sourceNode`, e.g.:
* `function foo(\* not leading comment for a *\ a: string) {}`
* The comment refers to `a` but belongs to the `(` token, but we might want to copy it.
*/
export function copyTrailingAsLeadingComments(sourceNode: Node, targetNode: Node, sourceFile: SourceFile, commentKind?: CommentKind, hasTrailingNewLine?: boolean) {
forEachTrailingCommentRange(sourceFile.text, sourceNode.pos, getAddCommentsFunction(targetNode, sourceFile, commentKind, hasTrailingNewLine, addSyntheticLeadingComment));
}
function getAddCommentsFunction(targetNode: Node, sourceFile: SourceFile, commentKind: CommentKind | undefined, hasTrailingNewLine: boolean | undefined, cb: (node: Node, kind: CommentKind, text: string, hasTrailingNewLine?: boolean) => void) {
return (pos: number, end: number, kind: CommentKind, htnl: boolean) => {
if (kind === SyntaxKind.MultiLineCommentTrivia) {
// Remove leading /*
pos += 2;
// Remove trailing */
end -= 2;
}
else {
// Remove leading //
pos += 2;
}
cb(targetNode, commentKind || kind, sourceFile.text.slice(pos, end), hasTrailingNewLine !== undefined ? hasTrailingNewLine : htnl);
};
}
function indexInTextChange(change: string, name: string): number {
if (startsWith(change, name)) return 0;
// Add a " " to avoid references inside words
let idx = change.indexOf(" " + name);
if (idx === -1) idx = change.indexOf("." + name);
if (idx === -1) idx = change.indexOf('"' + name);
return idx === -1 ? -1 : idx + 1;
}
/* @internal */
export function needsParentheses(expression: Expression): boolean {
return isBinaryExpression(expression) && expression.operatorToken.kind === SyntaxKind.CommaToken
|| isObjectLiteralExpression(expression)
|| isAsExpression(expression) && isObjectLiteralExpression(expression.expression);
}
export function getContextualTypeFromParent(node: Expression, checker: TypeChecker): Type | undefined {
const { parent } = node;
switch (parent.kind) {
case SyntaxKind.NewExpression:
return checker.getContextualType(parent as NewExpression);
case SyntaxKind.BinaryExpression: {
const { left, operatorToken, right } = parent as BinaryExpression;
return isEqualityOperatorKind(operatorToken.kind)
? checker.getTypeAtLocation(node === right ? left : right)
: checker.getContextualType(node);
}
case SyntaxKind.CaseClause:
return (parent as CaseClause).expression === node ? getSwitchedType(parent as CaseClause, checker) : undefined;
default:
return checker.getContextualType(node);
}
}
export function quote(sourceFile: SourceFile, preferences: UserPreferences, text: string): string {
// Editors can pass in undefined or empty string - we want to infer the preference in those cases.
const quotePreference = getQuotePreference(sourceFile, preferences);
const quoted = JSON.stringify(text);
return quotePreference === QuotePreference.Single ? `'${stripQuotes(quoted).replace(/'/g, "\\'").replace(/\\"/g, '"')}'` : quoted;
}
export function isEqualityOperatorKind(kind: SyntaxKind): kind is EqualityOperator {
switch (kind) {
case SyntaxKind.EqualsEqualsEqualsToken:
case SyntaxKind.EqualsEqualsToken:
case SyntaxKind.ExclamationEqualsEqualsToken:
case SyntaxKind.ExclamationEqualsToken:
return true;
default:
return false;
}
}
export function isStringLiteralOrTemplate(node: Node): node is StringLiteralLike | TemplateExpression | TaggedTemplateExpression {
switch (node.kind) {
case SyntaxKind.StringLiteral:
case SyntaxKind.NoSubstitutionTemplateLiteral:
case SyntaxKind.TemplateExpression:
case SyntaxKind.TaggedTemplateExpression:
return true;
default:
return false;
}
}
export function hasIndexSignature(type: Type): boolean {
return !!type.getStringIndexType() || !!type.getNumberIndexType();
}
export function getSwitchedType(caseClause: CaseClause, checker: TypeChecker): Type | undefined {
return checker.getTypeAtLocation(caseClause.parent.parent.expression);
}
export const ANONYMOUS = "anonymous function";
export function getTypeNodeIfAccessible(type: Type, enclosingScope: Node, program: Program, host: LanguageServiceHost): TypeNode | undefined {
const checker = program.getTypeChecker();
let typeIsAccessible = true;
const notAccessible = () => typeIsAccessible = false;
const res = checker.typeToTypeNode(type, enclosingScope, NodeBuilderFlags.NoTruncation, {
trackSymbol: (symbol, declaration, meaning) => {
typeIsAccessible = typeIsAccessible && checker.isSymbolAccessible(symbol, declaration, meaning, /*shouldComputeAliasToMarkVisible*/ false).accessibility === SymbolAccessibility.Accessible;
return !typeIsAccessible;
},
reportInaccessibleThisError: notAccessible,
reportPrivateInBaseOfClassExpression: notAccessible,
reportInaccessibleUniqueSymbolError: notAccessible,
moduleResolverHost: getModuleSpecifierResolverHost(program, host)
});
return typeIsAccessible ? res : undefined;
}
function syntaxRequiresTrailingCommaOrSemicolonOrASI(kind: SyntaxKind) {
return kind === SyntaxKind.CallSignature
|| kind === SyntaxKind.ConstructSignature
|| kind === SyntaxKind.IndexSignature
|| kind === SyntaxKind.PropertySignature
|| kind === SyntaxKind.MethodSignature;
}
function syntaxRequiresTrailingFunctionBlockOrSemicolonOrASI(kind: SyntaxKind) {
return kind === SyntaxKind.FunctionDeclaration
|| kind === SyntaxKind.Constructor
|| kind === SyntaxKind.MethodDeclaration
|| kind === SyntaxKind.GetAccessor
|| kind === SyntaxKind.SetAccessor;
}
function syntaxRequiresTrailingModuleBlockOrSemicolonOrASI(kind: SyntaxKind) {
return kind === SyntaxKind.ModuleDeclaration;
}
export function syntaxRequiresTrailingSemicolonOrASI(kind: SyntaxKind) {
return kind === SyntaxKind.VariableStatement
|| kind === SyntaxKind.ExpressionStatement
|| kind === SyntaxKind.DoStatement
|| kind === SyntaxKind.ContinueStatement
|| kind === SyntaxKind.BreakStatement
|| kind === SyntaxKind.ReturnStatement
|| kind === SyntaxKind.ThrowStatement
|| kind === SyntaxKind.DebuggerStatement
|| kind === SyntaxKind.PropertyDeclaration
|| kind === SyntaxKind.TypeAliasDeclaration
|| kind === SyntaxKind.ImportDeclaration
|| kind === SyntaxKind.ImportEqualsDeclaration
|| kind === SyntaxKind.ExportDeclaration
|| kind === SyntaxKind.NamespaceExportDeclaration
|| kind === SyntaxKind.ExportAssignment;
}
export const syntaxMayBeASICandidate = or(
syntaxRequiresTrailingCommaOrSemicolonOrASI,
syntaxRequiresTrailingFunctionBlockOrSemicolonOrASI,
syntaxRequiresTrailingModuleBlockOrSemicolonOrASI,
syntaxRequiresTrailingSemicolonOrASI);
function nodeIsASICandidate(node: Node, sourceFile: SourceFileLike): boolean {
const lastToken = node.getLastToken(sourceFile);
if (lastToken && lastToken.kind === SyntaxKind.SemicolonToken) {
return false;
}
if (syntaxRequiresTrailingCommaOrSemicolonOrASI(node.kind)) {
if (lastToken && lastToken.kind === SyntaxKind.CommaToken) {
return false;
}
}
else if (syntaxRequiresTrailingModuleBlockOrSemicolonOrASI(node.kind)) {
const lastChild = last(node.getChildren(sourceFile));
if (lastChild && isModuleBlock(lastChild)) {
return false;
}
}
else if (syntaxRequiresTrailingFunctionBlockOrSemicolonOrASI(node.kind)) {
const lastChild = last(node.getChildren(sourceFile));
if (lastChild && isFunctionBlock(lastChild)) {
return false;
}
}
else if (!syntaxRequiresTrailingSemicolonOrASI(node.kind)) {
return false;
}
// See comment in parser’s `parseDoStatement`
if (node.kind === SyntaxKind.DoStatement) {
return true;
}
const topNode = findAncestor(node, ancestor => !ancestor.parent)!;
const nextToken = findNextToken(node, topNode, sourceFile);
if (!nextToken || nextToken.kind === SyntaxKind.CloseBraceToken) {
return true;
}
const startLine = sourceFile.getLineAndCharacterOfPosition(node.getEnd()).line;
const endLine = sourceFile.getLineAndCharacterOfPosition(nextToken.getStart(sourceFile)).line;
return startLine !== endLine;
}
export function positionIsASICandidate(pos: number, context: Node, sourceFile: SourceFileLike): boolean {
const contextAncestor = findAncestor(context, ancestor => {
if (ancestor.end !== pos) {
return "quit";
}
return syntaxMayBeASICandidate(ancestor.kind);
});
return !!contextAncestor && nodeIsASICandidate(contextAncestor, sourceFile);
}
export function probablyUsesSemicolons(sourceFile: SourceFile): boolean {
let withSemicolon = 0;
let withoutSemicolon = 0;
const nStatementsToObserve = 5;
forEachChild(sourceFile, function visit(node): boolean | undefined {
if (syntaxRequiresTrailingSemicolonOrASI(node.kind)) {
const lastToken = node.getLastToken(sourceFile);
if (lastToken?.kind === SyntaxKind.SemicolonToken) {
withSemicolon++;
}
else {
withoutSemicolon++;
}
}
else if (syntaxRequiresTrailingCommaOrSemicolonOrASI(node.kind)) {
const lastToken = node.getLastToken(sourceFile);
if (lastToken?.kind === SyntaxKind.SemicolonToken) {
withSemicolon++;
}
else if (lastToken && lastToken.kind !== SyntaxKind.CommaToken) {
const lastTokenLine = getLineAndCharacterOfPosition(sourceFile, lastToken.getStart(sourceFile)).line;
const nextTokenLine = getLineAndCharacterOfPosition(sourceFile, getSpanOfTokenAtPosition(sourceFile, lastToken.end).start).line;
// Avoid counting missing semicolon in single-line objects:
// `function f(p: { x: string /*no semicolon here is insignificant*/ }) {`
if (lastTokenLine !== nextTokenLine) {
withoutSemicolon++;
}
}
}
if (withSemicolon + withoutSemicolon >= nStatementsToObserve) {
return true;
}
return forEachChild(node, visit);
});
// One statement missing a semicolon isn't sufficient evidence to say the user
// doesn’t want semicolons, because they may not even be done writing that statement.
if (withSemicolon === 0 && withoutSemicolon <= 1) {
return true;
}
// If even 2/5 places have a semicolon, the user probably wants semicolons
return withSemicolon / withoutSemicolon > 1 / nStatementsToObserve;
}
export function tryGetDirectories(host: Pick<LanguageServiceHost, "getDirectories">, directoryName: string): string[] {
return tryIOAndConsumeErrors(host, host.getDirectories, directoryName) || [];
}
export function tryReadDirectory(host: Pick<LanguageServiceHost, "readDirectory">, path: string, extensions?: readonly string[], exclude?: readonly string[], include?: readonly string[]): readonly string[] {
return tryIOAndConsumeErrors(host, host.readDirectory, path, extensions, exclude, include) || emptyArray;
}
export function tryFileExists(host: Pick<LanguageServiceHost, "fileExists">, path: string): boolean {
return tryIOAndConsumeErrors(host, host.fileExists, path);
}
export function tryDirectoryExists(host: LanguageServiceHost, path: string): boolean {
return tryAndIgnoreErrors(() => directoryProbablyExists(path, host)) || false;
}
export function tryAndIgnoreErrors<T>(cb: () => T): T | undefined {
try {
return cb();
}
catch {
return undefined;
}
}
export function tryIOAndConsumeErrors<T>(host: unknown, toApply: ((...a: any[]) => T) | undefined, ...args: any[]) {
return tryAndIgnoreErrors(() => toApply && toApply.apply(host, args));
}
export function findPackageJsons(startDirectory: string, host: Pick<LanguageServiceHost, "fileExists">, stopDirectory?: string): string[] {
const paths: string[] = [];
forEachAncestorDirectory(startDirectory, ancestor => {
if (ancestor === stopDirectory) {
return true;
}
const currentConfigPath = combinePaths(ancestor, "package.json");
if (tryFileExists(host, currentConfigPath)) {
paths.push(currentConfigPath);
}
});
return paths;
}
export function findPackageJson(directory: string, host: LanguageServiceHost): string | undefined {
let packageJson: string | undefined;
forEachAncestorDirectory(directory, ancestor => {
if (ancestor === "node_modules") return true;
packageJson = findConfigFile(ancestor, (f) => tryFileExists(host, f), "package.json");
if (packageJson) {
return true; // break out
}
});
return packageJson;
}
export function getPackageJsonsVisibleToFile(fileName: string, host: LanguageServiceHost): readonly PackageJsonInfo[] {
if (!host.fileExists) {
return [];
}
const packageJsons: PackageJsonInfo[] = [];
forEachAncestorDirectory(getDirectoryPath(fileName), ancestor => {
const packageJsonFileName = combinePaths(ancestor, "package.json");
if (host.fileExists!(packageJsonFileName)) {
const info = createPackageJsonInfo(packageJsonFileName, host);
if (info) {
packageJsons.push(info);
}
}
});
return packageJsons;
}
export function createPackageJsonInfo(fileName: string, host: { readFile?(fileName: string): string | undefined }): PackageJsonInfo | undefined {
if (!host.readFile) {
return undefined;
}
type PackageJsonRaw = Record<typeof dependencyKeys[number], Record<string, string> | undefined>;
const dependencyKeys = ["dependencies", "devDependencies", "optionalDependencies", "peerDependencies"] as const;
const stringContent = host.readFile(fileName) || "";
const content = tryParseJson(stringContent) as PackageJsonRaw | undefined;
const info: Pick<PackageJsonInfo, typeof dependencyKeys[number]> = {};
if (content) {
for (const key of dependencyKeys) {
const dependencies = content[key];
if (!dependencies) {
continue;
}
const dependencyMap = new Map<string, string>();
for (const packageName in dependencies) {
dependencyMap.set(packageName, dependencies[packageName]);
}
info[key] = dependencyMap;
}
}
const dependencyGroups = [
[PackageJsonDependencyGroup.Dependencies, info.dependencies],
[PackageJsonDependencyGroup.DevDependencies, info.devDependencies],
[PackageJsonDependencyGroup.OptionalDependencies, info.optionalDependencies],
[PackageJsonDependencyGroup.PeerDependencies, info.peerDependencies],
] as const;
return {
...info,
parseable: !!content,
fileName,
get,
has(dependencyName, inGroups) {
return !!get(dependencyName, inGroups);
},
};
function get(dependencyName: string, inGroups = PackageJsonDependencyGroup.All) {
for (const [group, deps] of dependencyGroups) {
if (deps && (inGroups & group)) {
const dep = deps.get(dependencyName);
if (dep !== undefined) {
return dep;
}
}
}
}
}
export interface PackageJsonImportFilter {
allowsImportingAmbientModule: (moduleSymbol: Symbol, moduleSpecifierResolutionHost: ModuleSpecifierResolutionHost) => boolean;
allowsImportingSourceFile: (sourceFile: SourceFile, moduleSpecifierResolutionHost: ModuleSpecifierResolutionHost) => boolean;
/**
* Use for a specific module specifier that has already been resolved.
* Use `allowsImportingAmbientModule` or `allowsImportingSourceFile` to resolve
* the best module specifier for a given module _and_ determine if it’s importable.
*/
allowsImportingSpecifier: (moduleSpecifier: string) => boolean;
}
export function createPackageJsonImportFilter(fromFile: SourceFile, preferences: UserPreferences, host: LanguageServiceHost): PackageJsonImportFilter {
const packageJsons = (
(host.getPackageJsonsVisibleToFile && host.getPackageJsonsVisibleToFile(fromFile.fileName)) || getPackageJsonsVisibleToFile(fromFile.fileName, host)
).filter(p => p.parseable);
let usesNodeCoreModules: boolean | undefined;
return { allowsImportingAmbientModule, allowsImportingSourceFile, allowsImportingSpecifier };
function moduleSpecifierIsCoveredByPackageJson(specifier: string) {
const packageName = getNodeModuleRootSpecifier(specifier);
for (const packageJson of packageJsons) {
if (packageJson.has(packageName) || packageJson.has(getTypesPackageName(packageName))) {
return true;
}
}
return false;
}
function allowsImportingAmbientModule(moduleSymbol: Symbol, moduleSpecifierResolutionHost: ModuleSpecifierResolutionHost): boolean {
if (!packageJsons.length || !moduleSymbol.valueDeclaration) {
return true;
}
const declaringSourceFile = moduleSymbol.valueDeclaration.getSourceFile();
const declaringNodeModuleName = getNodeModulesPackageNameFromFileName(declaringSourceFile.fileName, moduleSpecifierResolutionHost);
if (typeof declaringNodeModuleName === "undefined") {
return true;
}
const declaredModuleSpecifier = stripQuotes(moduleSymbol.getName());
if (isAllowedCoreNodeModulesImport(declaredModuleSpecifier)) {
return true;
}
return moduleSpecifierIsCoveredByPackageJson(declaringNodeModuleName)
|| moduleSpecifierIsCoveredByPackageJson(declaredModuleSpecifier);
}
function allowsImportingSourceFile(sourceFile: SourceFile, moduleSpecifierResolutionHost: ModuleSpecifierResolutionHost): boolean {
if (!packageJsons.length) {
return true;
}
const moduleSpecifier = getNodeModulesPackageNameFromFileName(sourceFile.fileName, moduleSpecifierResolutionHost);
if (!moduleSpecifier) {
return true;
}
return moduleSpecifierIsCoveredByPackageJson(moduleSpecifier);
}
function allowsImportingSpecifier(moduleSpecifier: string) {
if (!packageJsons.length || isAllowedCoreNodeModulesImport(moduleSpecifier)) {
return true;
}
if (pathIsRelative(moduleSpecifier) || isRootedDiskPath(moduleSpecifier)) {
return true;
}
return moduleSpecifierIsCoveredByPackageJson(moduleSpecifier);
}
function isAllowedCoreNodeModulesImport(moduleSpecifier: string) {
// If we’re in JavaScript, it can be difficult to tell whether the user wants to import
// from Node core modules or not. We can start by seeing if the user is actually using
// any node core modules, as opposed to simply having @types/node accidentally as a
// dependency of a dependency.
if (isSourceFileJS(fromFile) && JsTyping.nodeCoreModules.has(moduleSpecifier)) {
if (usesNodeCoreModules === undefined) {
usesNodeCoreModules = consumesNodeCoreModules(fromFile);
}
if (usesNodeCoreModules) {
return true;
}
}
return false;
}
function getNodeModulesPackageNameFromFileName(importedFileName: string, moduleSpecifierResolutionHost: ModuleSpecifierResolutionHost): string | undefined {
if (!stringContains(importedFileName, "node_modules")) {
return undefined;
}
const specifier = moduleSpecifiers.getNodeModulesPackageName(
host.getCompilationSettings(),
fromFile,
importedFileName,
moduleSpecifierResolutionHost,
preferences,
);
if (!specifier) {
return undefined;
}
// Paths here are not node_modules, so we don’t care about them;
// returning anything will trigger a lookup in package.json.
if (!pathIsRelative(specifier) && !isRootedDiskPath(specifier)) {
return getNodeModuleRootSpecifier(specifier);
}
}
function getNodeModuleRootSpecifier(fullSpecifier: string): string {
const components = getPathComponents(getPackageNameFromTypesPackageName(fullSpecifier)).slice(1);
// Scoped packages
if (startsWith(components[0], "@")) {
return `${components[0]}/${components[1]}`;
}
return components[0];
}
}
function tryParseJson(text: string) {
try {
return JSON.parse(text);
}
catch {
return undefined;
}
}
export function consumesNodeCoreModules(sourceFile: SourceFile): boolean {
return some(sourceFile.imports, ({ text }) => JsTyping.nodeCoreModules.has(text));
}
export function isInsideNodeModules(fileOrDirectory: string): boolean {
return contains(getPathComponents(fileOrDirectory), "node_modules");
}
export function isDiagnosticWithLocation(diagnostic: Diagnostic): diagnostic is DiagnosticWithLocation {
return diagnostic.file !== undefined && diagnostic.start !== undefined && diagnostic.length !== undefined;
}
export function findDiagnosticForNode(node: Node, sortedFileDiagnostics: readonly Diagnostic[]): DiagnosticWithLocation | undefined {
const span: Partial<TextSpan> = createTextSpanFromNode(node);
const index = binarySearchKey(sortedFileDiagnostics, span, identity, compareTextSpans);
if (index >= 0) {
const diagnostic = sortedFileDiagnostics[index];
Debug.assertEqual(diagnostic.file, node.getSourceFile(), "Diagnostics proided to 'findDiagnosticForNode' must be from a single SourceFile");
return cast(diagnostic, isDiagnosticWithLocation);
}
}
export function getDiagnosticsWithinSpan(span: TextSpan, sortedFileDiagnostics: readonly Diagnostic[]): readonly DiagnosticWithLocation[] {
let index = binarySearchKey(sortedFileDiagnostics, span.start, diag => diag.start, compareValues);
if (index < 0) {
index = ~index;
}
while (sortedFileDiagnostics[index - 1]?.start === span.start) {
index--;
}
const result: DiagnosticWithLocation[] = [];
const end = textSpanEnd(span);
while (true) {
const diagnostic = tryCast(sortedFileDiagnostics[index], isDiagnosticWithLocation);
if (!diagnostic || diagnostic.start > end) {
break;
}
if (textSpanContainsTextSpan(span, diagnostic)) {
result.push(diagnostic);
}
index++;
}
return result;
}
/* @internal */
export function getRefactorContextSpan({ startPosition, endPosition }: RefactorContext): TextSpan {
return createTextSpanFromBounds(startPosition, endPosition === undefined ? startPosition : endPosition);
}
/* @internal */
export function getFixableErrorSpanExpression(sourceFile: SourceFile, span: TextSpan): Expression | undefined {
const token = getTokenAtPosition(sourceFile, span.start);
// Checker has already done work to determine that await might be possible, and has attached
// related info to the node, so start by finding the expression that exactly matches up
// with the diagnostic range.
const expression = findAncestor(token, node => {
if (node.getStart(sourceFile) < span.start || node.getEnd() > textSpanEnd(span)) {
return "quit";
}
return isExpression(node) && textSpansEqual(span, createTextSpanFromNode(node, sourceFile));
}) as Expression | undefined;
return expression;
}
/**
* If the provided value is an array, the mapping function is applied to each element; otherwise, the mapping function is applied
* to the provided value itself.
*/
export function mapOneOrMany<T, U>(valueOrArray: T | readonly T[], f: (x: T, i: number) => U): U | U[];
export function mapOneOrMany<T, U>(valueOrArray: T | readonly T[] | undefined, f: (x: T, i: number) => U): U | U[] | undefined;
export function mapOneOrMany<T, U>(valueOrArray: T | readonly T[], f: (x: T, i: number) => U, resultSelector: (x: U[]) => U): U;
export function mapOneOrMany<T, U>(valueOrArray: T | readonly T[] | undefined, f: (x: T, i: number) => U, resultSelector: (x: U[]) => U): U | undefined;
export function mapOneOrMany<T, U>(valueOrArray: T | readonly T[] | undefined, f: (x: T, i: number) => U, resultSelector: (x: U[]) => U | U[] = identity): U | U[] | undefined {
return valueOrArray ? isArray(valueOrArray) ? resultSelector(map(valueOrArray, f)) : f(valueOrArray, 0) : undefined;
}
/**
* If the provided value is an array, the first element of the array is returned; otherwise, the provided value is returned instead.
*/
export function firstOrOnly<T>(valueOrArray: T | readonly T[]): T {
return isArray(valueOrArray) ? first(valueOrArray) : valueOrArray;
}
export function getNameForExportedSymbol(symbol: Symbol, scriptTarget: ScriptTarget | undefined, preferCapitalized?: boolean) {
if (!(symbol.flags & SymbolFlags.Transient) && (symbol.escapedName === InternalSymbolName.ExportEquals || symbol.escapedName === InternalSymbolName.Default)) {
// Name of "export default foo;" is "foo". Name of "export default 0" is the filename converted to camelCase.
return firstDefined(symbol.declarations, d => isExportAssignment(d) ? tryCast(skipOuterExpressions(d.expression), isIdentifier)?.text : undefined)
|| codefix.moduleSymbolToValidIdentifier(getSymbolParentOrFail(symbol), scriptTarget, !!preferCapitalized);
}
return symbol.name;
}
function getSymbolParentOrFail(symbol: Symbol) {
return Debug.checkDefined(
symbol.parent,
`Symbol parent was undefined. Flags: ${Debug.formatSymbolFlags(symbol.flags)}. ` +
`Declarations: ${symbol.declarations?.map(d => {
const kind = Debug.formatSyntaxKind(d.kind);
const inJS = isInJSFile(d);
const { expression } = d as any;
return (inJS ? "[JS]" : "") + kind + (expression ? ` (expression: ${Debug.formatSyntaxKind(expression.kind)})` : "");
}).join(", ")}.`);
}
/**
* Useful to check whether a string contains another string at a specific index
* without allocating another string or traversing the entire contents of the outer string.
*
* This function is useful in place of either of the following:
*
* ```ts
* // Allocates
* haystack.substr(startIndex, needle.length) === needle
*
* // Full traversal
* haystack.indexOf(needle, startIndex) === startIndex
* ```
*
* @param haystack The string that potentially contains `needle`.
* @param needle The string whose content might sit within `haystack`.
* @param startIndex The index within `haystack` to start searching for `needle`.
*/
export function stringContainsAt(haystack: string, needle: string, startIndex: number) {
const needleLength = needle.length;
if (needleLength + startIndex > haystack.length) {
return false;
}
for (let i = 0; i < needleLength; i++) {
if (needle.charCodeAt(i) !== haystack.charCodeAt(i + startIndex)) return false;
}
return true;
}
export function startsWithUnderscore(name: string): boolean {
return name.charCodeAt(0) === CharacterCodes._;
}
export function isGlobalDeclaration(declaration: Declaration) {
return !isNonGlobalDeclaration(declaration);
}
export function isNonGlobalDeclaration(declaration: Declaration) {
const sourceFile = declaration.getSourceFile();
// If the file is not a module, the declaration is global
if (!sourceFile.externalModuleIndicator && !sourceFile.commonJsModuleIndicator) {
return false;
}
// If the file is a module written in TypeScript, it still might be in a `declare global` augmentation
return isInJSFile(declaration) || !findAncestor(declaration, isGlobalScopeAugmentation);
}
export function isDeprecatedDeclaration(decl: Declaration) {
return !!(getCombinedNodeFlagsAlwaysIncludeJSDoc(decl) & ModifierFlags.Deprecated);
}
export function shouldUseUriStyleNodeCoreModules(file: SourceFile, program: Program): boolean {
const decisionFromFile = firstDefined(file.imports, node => {
if (JsTyping.nodeCoreModules.has(node.text)) {
return startsWith(node.text, "node:");
}
});
return decisionFromFile ?? program.usesUriStyleNodeCoreModules;
}
export function getNewLineKind(newLineCharacter: string): NewLineKind {
return newLineCharacter === "\n" ? NewLineKind.LineFeed : NewLineKind.CarriageReturnLineFeed;
}
export type DiagnosticAndArguments = DiagnosticMessage | [DiagnosticMessage, string] | [DiagnosticMessage, string, string];
export function diagnosticToString(diag: DiagnosticAndArguments): string {
return isArray(diag)
? formatStringFromArgs(getLocaleSpecificMessage(diag[0]), diag.slice(1) as readonly string[])
: getLocaleSpecificMessage(diag);
}
/**
* Get format code settings for a code writing context (e.g. when formatting text changes or completions code).
*/
export function getFormatCodeSettingsForWriting({ options }: formatting.FormatContext, sourceFile: SourceFile): FormatCodeSettings {
const shouldAutoDetectSemicolonPreference = !options.semicolons || options.semicolons === SemicolonPreference.Ignore;
const shouldRemoveSemicolons = options.semicolons === SemicolonPreference.Remove || shouldAutoDetectSemicolonPreference && !probablyUsesSemicolons(sourceFile);
return {
...options,
semicolons: shouldRemoveSemicolons ? SemicolonPreference.Remove : SemicolonPreference.Ignore,
};
}
// #endregion
}