processCodePathToEnter() — react Function Reference

Source Code

packages/eslint-plugin-react-hooks/src/code-path-analysis/code-path-analyzer.js lines 380–520

function processCodePathToEnter(analyzer, node) {
  let codePath = analyzer.codePath;
  let state = codePath && CodePath.getState(codePath);
  const parent = node.parent;

  /**
   * Creates a new code path and trigger the onCodePathStart event
   * based on the currently selected node.
   * @param {string} origin The reason the code path was started.
   * @returns {void}
   */
  function startCodePath(origin) {
    if (codePath) {
      // Emits onCodePathSegmentStart events if updated.
      forwardCurrentToHead(analyzer, node);
    }

    // Create the code path of this scope.
    codePath = analyzer.codePath = new CodePath({
      id: analyzer.idGenerator.next(),
      origin,
      upper: codePath,
      onLooped: analyzer.onLooped,
    });
    state = CodePath.getState(codePath);

    // Emits onCodePathStart events.
    analyzer.emitter.emit('onCodePathStart', codePath, node);
  }

  /*
   * Special case: The right side of class field initializer is considered
   * to be its own function, so we need to start a new code path in this
   * case.
   */
  if (isPropertyDefinitionValue(node)) {
    startCodePath('class-field-initializer');

    /*
     * Intentional fall through because `node` needs to also be
     * processed by the code below. For example, if we have:
     *
     * class Foo {
     *     a = () => {}
     * }
     *
     * In this case, we also need start a second code path.
     */
  }

  switch (node.type) {
    case 'Program':
      startCodePath('program');
      break;

    case 'FunctionDeclaration':
    case 'ComponentDeclaration':
    case 'HookDeclaration':
    case 'FunctionExpression':
    case 'ArrowFunctionExpression':
      startCodePath('function');
      break;

    case 'StaticBlock':
      startCodePath('class-static-block');
      break;

    case 'ChainExpression':
      state.pushChainContext();
      break;
    case 'CallExpression':
      if (node.optional === true) {
        state.makeOptionalNode();
      }
      break;
    case 'MemberExpression':
      if (node.optional === true) {
        state.makeOptionalNode();
      }
      break;