in go/ast/astutil/rewrite.go [187:454]
func (a *application) apply(parent ast.Node, name string, iter *iterator, n ast.Node) {
// convert typed nil into untyped nil
if v := reflect.ValueOf(n); v.Kind() == reflect.Ptr && v.IsNil() {
n = nil
}
// avoid heap-allocating a new cursor for each apply call; reuse a.cursor instead
saved := a.cursor
a.cursor.parent = parent
a.cursor.name = name
a.cursor.iter = iter
a.cursor.node = n
if a.pre != nil && !a.pre(&a.cursor) {
a.cursor = saved
return
}
// walk children
// (the order of the cases matches the order of the corresponding node types in go/ast)
switch n := n.(type) {
case nil:
// nothing to do
// Comments and fields
case *ast.Comment:
// nothing to do
case *ast.CommentGroup:
if n != nil {
a.applyList(n, "List")
}
case *ast.Field:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Names")
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Tag", nil, n.Tag)
a.apply(n, "Comment", nil, n.Comment)
case *ast.FieldList:
a.applyList(n, "List")
// Expressions
case *ast.BadExpr, *ast.Ident, *ast.BasicLit:
// nothing to do
case *ast.Ellipsis:
a.apply(n, "Elt", nil, n.Elt)
case *ast.FuncLit:
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Body", nil, n.Body)
case *ast.CompositeLit:
a.apply(n, "Type", nil, n.Type)
a.applyList(n, "Elts")
case *ast.ParenExpr:
a.apply(n, "X", nil, n.X)
case *ast.SelectorExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Sel", nil, n.Sel)
case *ast.IndexExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Index", nil, n.Index)
case *typeparams.IndexListExpr:
a.apply(n, "X", nil, n.X)
a.applyList(n, "Indices")
case *ast.SliceExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Low", nil, n.Low)
a.apply(n, "High", nil, n.High)
a.apply(n, "Max", nil, n.Max)
case *ast.TypeAssertExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Type", nil, n.Type)
case *ast.CallExpr:
a.apply(n, "Fun", nil, n.Fun)
a.applyList(n, "Args")
case *ast.StarExpr:
a.apply(n, "X", nil, n.X)
case *ast.UnaryExpr:
a.apply(n, "X", nil, n.X)
case *ast.BinaryExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Y", nil, n.Y)
case *ast.KeyValueExpr:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
// Types
case *ast.ArrayType:
a.apply(n, "Len", nil, n.Len)
a.apply(n, "Elt", nil, n.Elt)
case *ast.StructType:
a.apply(n, "Fields", nil, n.Fields)
case *ast.FuncType:
a.apply(n, "Params", nil, n.Params)
a.apply(n, "Results", nil, n.Results)
case *ast.InterfaceType:
a.apply(n, "Methods", nil, n.Methods)
case *ast.MapType:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
case *ast.ChanType:
a.apply(n, "Value", nil, n.Value)
// Statements
case *ast.BadStmt:
// nothing to do
case *ast.DeclStmt:
a.apply(n, "Decl", nil, n.Decl)
case *ast.EmptyStmt:
// nothing to do
case *ast.LabeledStmt:
a.apply(n, "Label", nil, n.Label)
a.apply(n, "Stmt", nil, n.Stmt)
case *ast.ExprStmt:
a.apply(n, "X", nil, n.X)
case *ast.SendStmt:
a.apply(n, "Chan", nil, n.Chan)
a.apply(n, "Value", nil, n.Value)
case *ast.IncDecStmt:
a.apply(n, "X", nil, n.X)
case *ast.AssignStmt:
a.applyList(n, "Lhs")
a.applyList(n, "Rhs")
case *ast.GoStmt:
a.apply(n, "Call", nil, n.Call)
case *ast.DeferStmt:
a.apply(n, "Call", nil, n.Call)
case *ast.ReturnStmt:
a.applyList(n, "Results")
case *ast.BranchStmt:
a.apply(n, "Label", nil, n.Label)
case *ast.BlockStmt:
a.applyList(n, "List")
case *ast.IfStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Cond", nil, n.Cond)
a.apply(n, "Body", nil, n.Body)
a.apply(n, "Else", nil, n.Else)
case *ast.CaseClause:
a.applyList(n, "List")
a.applyList(n, "Body")
case *ast.SwitchStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Tag", nil, n.Tag)
a.apply(n, "Body", nil, n.Body)
case *ast.TypeSwitchStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Assign", nil, n.Assign)
a.apply(n, "Body", nil, n.Body)
case *ast.CommClause:
a.apply(n, "Comm", nil, n.Comm)
a.applyList(n, "Body")
case *ast.SelectStmt:
a.apply(n, "Body", nil, n.Body)
case *ast.ForStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Cond", nil, n.Cond)
a.apply(n, "Post", nil, n.Post)
a.apply(n, "Body", nil, n.Body)
case *ast.RangeStmt:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
a.apply(n, "X", nil, n.X)
a.apply(n, "Body", nil, n.Body)
// Declarations
case *ast.ImportSpec:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Path", nil, n.Path)
a.apply(n, "Comment", nil, n.Comment)
case *ast.ValueSpec:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Names")
a.apply(n, "Type", nil, n.Type)
a.applyList(n, "Values")
a.apply(n, "Comment", nil, n.Comment)
case *ast.TypeSpec:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Comment", nil, n.Comment)
case *ast.BadDecl:
// nothing to do
case *ast.GenDecl:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Specs")
case *ast.FuncDecl:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Recv", nil, n.Recv)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Body", nil, n.Body)
// Files and packages
case *ast.File:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.applyList(n, "Decls")
// Don't walk n.Comments; they have either been walked already if
// they are Doc comments, or they can be easily walked explicitly.
case *ast.Package:
// collect and sort names for reproducible behavior
var names []string
for name := range n.Files {
names = append(names, name)
}
sort.Strings(names)
for _, name := range names {
a.apply(n, name, nil, n.Files[name])
}
default:
panic(fmt.Sprintf("Apply: unexpected node type %T", n))
}
if a.post != nil && !a.post(&a.cursor) {
panic(abort)
}
a.cursor = saved
}