Method processComment

packages/babel-parser/src/parser/comments.ts:114–149

* Given a newly created AST node _n_, attach _n_ to a comment whitespace _w_ if applicable * {@see CommentWhitespace}

(node: Node)

   * {@see {@link CommentWhitespace}}
   */
  processComment(node: Node): void {
    const { commentStack } = this.state;
    const commentStackLength = commentStack.length;
    if (commentStackLength === 0) return;
    let i = commentStackLength - 1;
    const lastCommentWS = commentStack[i];

    if (lastCommentWS.start === node.end) {
      lastCommentWS.leadingNode = node;
      i--;
    }

    const nodeStart = node.start!;
    // invariant: for all 0 <= j <= i, let c = commentStack[j], c must satisfy c.end < node.end
    for (; i >= 0; i--) {
      const commentWS = commentStack[i];
      const commentEnd = commentWS.end;
      if (commentEnd > nodeStart) {
        // by definition of commentWhiteSpace, this implies commentWS.start > nodeStart
        // so node can be a containingNode candidate. At this time we can finalize the comment
        // whitespace, because
        // 1) its leadingNode or trailingNode, if exists, will not change
        // 2) its containingNode have been assigned and will not change because it is the
        //    innermost minimal-sized AST node
        commentWS.containingNode = node;
        this.finalizeComment(commentWS);
        commentStack.splice(i, 1);
      } else {
        if (commentEnd === nodeStart) {
          commentWS.trailingNode = node;
        }
        // stop the loop when commentEnd <= nodeStart
        break;
      }
    }
  }

  /**
   * Assign the comments of comment whitespaces to related AST nodes.