angular-cli/packages/ast-tools/src/node.ts

import ts = require('typescript');
import {RemoveChange, Change} from './change';


/**
 * Find all nodes from the AST in the subtree of node of SyntaxKind kind.
 * @param node
 * @param kind
 * @param max The maximum number of items to return.
 * @return all nodes of kind, or [] if none is found
 */
export function findNodes(node: ts.Node, kind: ts.SyntaxKind, max: number = Infinity): ts.Node[] {
  if (!node || max == 0) {
    return [];
  }

  let arr: ts.Node[] = [];
  if (node.kind === kind) {
    arr.push(node);
    max--;
  }
  if (max > 0) {
    for (const child of node.getChildren()) {
      findNodes(child, kind, max).forEach(node => {
        if (max > 0) {
          arr.push(node);
        }
        max--;
      });

      if (max <= 0) {
        break;
      }
    }
  }
  return arr;
}


export function removeAstNode(node: ts.Node): Change {
  const source = node.getSourceFile();
  return new RemoveChange(
    source.path,
    node.getStart(source),
    node.getFullText(source)
  );
}