CodePathState Class — react Architecture

Source Code

packages/eslint-plugin-react-hooks/src/code-path-analysis/code-path-state.js lines 222–1439

class CodePathState {
  /**
   * @param {IdGenerator} idGenerator An id generator to generate id for code
   *   path segments.
   * @param {Function} onLooped A callback function to notify looping.
   */
  constructor(idGenerator, onLooped) {
    this.idGenerator = idGenerator;
    this.notifyLooped = onLooped;
    this.forkContext = ForkContext.newRoot(idGenerator);
    this.choiceContext = null;
    this.switchContext = null;
    this.tryContext = null;
    this.loopContext = null;
    this.breakContext = null;
    this.chainContext = null;

    this.currentSegments = [];
    this.initialSegment = this.forkContext.head[0];

    // returnedSegments and thrownSegments push elements into finalSegments also.
    const final = (this.finalSegments = []);
    const returned = (this.returnedForkContext = []);
    const thrown = (this.thrownForkContext = []);

    returned.add = addToReturnedOrThrown.bind(null, returned, thrown, final);
    thrown.add = addToReturnedOrThrown.bind(null, thrown, returned, final);
  }

  /**
   * The head segments.
   * @type {CodePathSegment[]}
   */
  get headSegments() {
    return this.forkContext.head;
  }

  /**
   * The parent forking context.
   * This is used for the root of new forks.
   * @type {ForkContext}
   */
  get parentForkContext() {
    const current = this.forkContext;

    return current && current.upper;
  }

  /**
   * Creates and stacks new forking context.
   * @param {boolean} forkLeavingPath A flag which shows being in a
   *   "finally" block.
   * @returns {ForkContext} The created context.
   */
  pushForkContext(forkLeavingPath) {
    this.forkContext = ForkContext.newEmpty(this.forkContext, forkLeavingPath);

    return this.forkContext;
  }

  /**
   * Pops and merges the last forking context.
   * @returns {ForkContext} The last context.
   */
  popForkContext() {
    const lastContext = this.forkContext;

    this.forkContext = lastContext.upper;
    this.forkContext.replaceHead(lastContext.makeNext(0, -1));

    return lastContext;
  }

  /**
   * Creates a new path.
   * @returns {void}
   */
  forkPath() {
    this.forkContext.add(this.parentForkContext.makeNext(-1, -1));
  }