function generateEventHandlerAttrForRax()

in modules/code-generator/src/plugins/component/rax/jsx.ts [257:326]
63 lines of code
5 McCabe index (conditional complexity)

function generateEventHandlerAttrForRax(
  attrName: string,
  attrValue: IPublicTypeCompositeValue,
  scope: IScope,
  config?: NodeGeneratorConfig,
): CodePiece[] {
  // -- 事件处理函数中 JSExpression 转成 JSFunction 来处理，避免当 JSExpression 处理的时候多包一层 eval 而导致 Rax 转码成小程序的时候出问题
  const valueExpr = generateCompositeType(
    isJSExpression(attrValue) ? { type: 'JSFunction', value: attrValue.value } : attrValue,
    scope,
    {
      handlers: config?.handlers,
    },
  );

  // 查询当前作用域下的变量
  const currentScopeVariables = scope.bindings?.getAllBindings() || [];
  if (currentScopeVariables.length <= 0) {
    return [
      {
        type: PIECE_TYPE.ATTR,
        name: attrName,
        value: valueExpr,
      },
    ];
  }

  // 提取出所有的未定义的全局变量
  const undeclaredVariablesInValueExpr = parseExpressionGetGlobalVariables(valueExpr);
  const referencedLocalVariables = _.intersection(
    undeclaredVariablesInValueExpr,
    currentScopeVariables,
  );
  if (referencedLocalVariables.length <= 0) {
    return [
      {
        type: PIECE_TYPE.ATTR,
        name: attrName,
        value: valueExpr,
      },
    ];
  }

  const wrappedAttrValueExpr = [
    '(...__$$args) => {',
    '  if (__$$isMiniApp) {',
    '    const __$$event = __$$args[0];',
    ...referencedLocalVariables.map(
      (localVar) => `const ${localVar} = __$$event.target.dataset.${localVar};`,
    ),
    `    return (${valueExpr}).apply(this, __$$args);`,
    '  } else {',
    `    return (${valueExpr}).apply(this, __$$args);`,
    '  }',
    '}',
  ].join('\n');

  return [
    ...referencedLocalVariables.map((localVar) => ({
      type: PIECE_TYPE.ATTR,
      name: `data-${changeCase.snake(localVar)}`,
      value: localVar,
    })),
    {
      type: PIECE_TYPE.ATTR,
      name: attrName,
      value: wrappedAttrValueExpr,
    },
  ];
}