angular/packages/compiler/test/ml_parser/ast_spec_utils.ts

/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */

import * as html from '../../src/ml_parser/ast';
import {ParseTreeResult} from '../../src/ml_parser/parser';
import {ParseLocation} from '../../src/parse_util';

export function humanizeDom(parseResult: ParseTreeResult, addSourceSpan: boolean = false): any[] {
  if (parseResult.errors.length > 0) {
    const errorString = parseResult.errors.join('\n');
    throw new Error(`Unexpected parse errors:\n${errorString}`);
  }

  return humanizeNodes(parseResult.rootNodes, addSourceSpan);
}

export function humanizeDomSourceSpans(parseResult: ParseTreeResult): any[] {
  return humanizeDom(parseResult, true);
}

export function humanizeNodes(nodes: html.Node[], addSourceSpan: boolean = false): any[] {
  const humanizer = new _Humanizer(addSourceSpan);
  html.visitAll(humanizer, nodes);
  return humanizer.result;
}

export function humanizeLineColumn(location: ParseLocation): string {
  return `${location.line}:${location.col}`;
}

class _Humanizer implements html.Visitor {
  result: any[] = [];
  elDepth: number = 0;

  constructor(private includeSourceSpan: boolean) {}

  visitElement(element: html.Element, context: any): any {
    const res = this._appendContext(element, [html.Element, element.name, this.elDepth++]);
    if (this.includeSourceSpan) {
      res.push(element.startSourceSpan.toString() ?? null);
      res.push(element.endSourceSpan?.toString() ?? null);
    }
    this.result.push(res);
    html.visitAll(this, element.attrs);
    html.visitAll(this, element.children);
    this.elDepth--;
  }

  visitAttribute(attribute: html.Attribute, context: any): any {
    const valueTokens = attribute.valueTokens ?? [];
    const res = this._appendContext(attribute, [
      html.Attribute, attribute.name, attribute.value, ...valueTokens.map(token => token.parts)
    ]);
    this.result.push(res);
  }

  visitText(text: html.Text, context: any): any {
    const res = this._appendContext(
        text, [html.Text, text.value, this.elDepth, ...text.tokens.map(token => token.parts)]);
    this.result.push(res);
  }

  visitComment(comment: html.Comment, context: any): any {
    const res = this._appendContext(comment, [html.Comment, comment.value, this.elDepth]);
    this.result.push(res);
  }

  visitExpansion(expansion: html.Expansion, context: any): any {
    const res = this._appendContext(
        expansion, [html.Expansion, expansion.switchValue, expansion.type, this.elDepth++]);
    this.result.push(res);
    html.visitAll(this, expansion.cases);
    this.elDepth--;
  }

  visitExpansionCase(expansionCase: html.ExpansionCase, context: any): any {
    const res =
        this._appendContext(expansionCase, [html.ExpansionCase, expansionCase.value, this.elDepth]);
    this.result.push(res);
  }

  visitBlock(block: html.Block, context: any) {
    const res = this._appendContext(block, [html.Block, block.name, this.elDepth++]);
    if (this.includeSourceSpan) {
      res.push(block.startSourceSpan.toString() ?? null);
      res.push(block.endSourceSpan?.toString() ?? null);
    }
    this.result.push(res);
    html.visitAll(this, block.parameters);
    html.visitAll(this, block.children);
    this.elDepth--;
  }

  visitBlockParameter(parameter: html.BlockParameter, context: any) {
    this.result.push(this._appendContext(parameter, [html.BlockParameter, parameter.expression]));
  }

  private _appendContext(ast: html.Node, input: any[]): any[] {
    if (!this.includeSourceSpan) return input;
    input.push(ast.sourceSpan.toString());
    if (ast.sourceSpan.fullStart.offset !== ast.sourceSpan.start.offset) {
      input.push(ast.sourceSpan.fullStart.file.content.substring(
          ast.sourceSpan.fullStart.offset, ast.sourceSpan.end.offset));
    }
    return input;
  }
}