Tobias Bosch cdc882bd36 feat: introduce source maps for templates (#15011)
The main use case for the generated source maps is to give
errors a meaningful context in terms of the original source
that the user wrote.

Related changes that are included in this commit:

* renamed virtual folders used for jit:
  * ng://<module type>/module.ngfactory.js
  * ng://<module type>/<comp type>.ngfactory.js
  * ng://<module type>/<comp type>.html (for inline templates)
* error logging:
  * all errors that happen in templates are logged
    from the place of the nearest element.
  * instead of logging error messages and stacks separately,
    we log the actual error. This is needed so that browsers apply
    source maps to the stack correctly.
  * error type and error is logged as one log entry.

Note that long-stack-trace zone has a bug that 
disables source maps for stack traces,
see https://github.com/angular/zone.js/issues/661.

BREAKING CHANGE:

- DebugNode.source no more returns the source location of a node.  

Closes 14013
2017-03-14 09:16:15 -07:00

38 lines
1.3 KiB
TypeScript

/**
* @license
* Copyright Google Inc. 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 {SourceMap} from '@angular/compiler/src/output/source_map';
const b64 = require('base64-js');
const SourceMapConsumer = require('source-map').SourceMapConsumer;
export interface SourceLocation {
line: number;
column: number;
source: string;
}
export function originalPositionFor(
sourceMap: SourceMap, genPosition: {line: number, column: number}): SourceLocation {
const smc = new SourceMapConsumer(sourceMap);
// Note: We don't return the original object as it also contains a `name` property
// which is always null and we don't want to include that in our assertions...
const {line, column, source} = smc.originalPositionFor(genPosition);
return {line, column, source};
}
export function extractSourceMap(source: string): SourceMap {
let idx = source.lastIndexOf('\n//#');
if (idx == -1) return null;
const smComment = source.slice(idx).trim();
const smB64 = smComment.split('sourceMappingURL=data:application/json;base64,')[1];
return smB64 ? JSON.parse(decodeB64String(smB64)) : null;
}
function decodeB64String(s: string): string {
return b64.toByteArray(s).reduce((s: string, c: number) => s + String.fromCharCode(c), '');
}