Class ActionList

packages/angular_devkit/schematics/src/tree/action.ts:27–156

let _id = 1;

export class ActionList implements Iterable<Action> {
  private _actions: Action[] = [];

  protected _action(action: Partial<Action>): void {
    this._actions.push({
      ...(action as Action),
      id: _id++,
      parent: this._actions.at(-1)?.id ?? 0,
    });
  }

  create(path: Path, content: Buffer): void {
    this._action({ kind: 'c', path, content });
  }
  overwrite(path: Path, content: Buffer): void {
    this._action({ kind: 'o', path, content });
  }
  rename(path: Path, to: Path): void {
    this._action({ kind: 'r', path, to });
  }
  delete(path: Path): void {
    this._action({ kind: 'd', path });
  }

  optimize(): void {
    const toCreate = new Map<Path, Buffer>();
    const toRename = new Map<Path, Path>();
    const toOverwrite = new Map<Path, Buffer>();
    const toDelete = new Set<Path>();

    for (const action of this._actions) {
      switch (action.kind) {
        case 'c':
          toCreate.set(action.path, action.content);
          break;

        case 'o':
          if (toCreate.has(action.path)) {
            toCreate.set(action.path, action.content);
          } else {
            toOverwrite.set(action.path, action.content);
          }
          break;

        case 'd':
          toDelete.add(action.path);
          break;

        case 'r': {
          const maybeCreate = toCreate.get(action.path);
          const maybeOverwrite = toOverwrite.get(action.path);
          if (maybeCreate) {
            toCreate.delete(action.path);
            toCreate.set(action.to, maybeCreate);
          }
          if (maybeOverwrite) {
            toOverwrite.delete(action.path);
            toOverwrite.set(action.to, maybeOverwrite);