blob: 4b9f04583501d0acc329ec420056370bc9dddc7a [file] [log] [blame]
// Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
library test.src.runner.browser.lazy_mapping;
import 'package:js/js.dart';
import 'package:path/path.dart' as p;
import 'package:source_maps/source_maps.dart' as source_maps;
import 'package:source_span/source_span.dart';
external Object _getSourceMap(String module);
/// The URL beneath which test files are served on the browser.
final _rootUrl = p.joinAll(p.split(p.current).take(2));
/// A source mapping that loads source maps as-needed using [_getSourceMap].
class LazyMapping extends source_maps.Mapping {
final _bundle = new source_maps.MappingBundle();
source_maps.SourceMapSpan spanFor(int line, int column,
{Map<String, SourceFile> files, String uri}) {
if (!_bundle.containsMapping(uri)) {
var module = uri.endsWith("/dart_sdk.js")
? "dart_sdk"
: p.withoutExtension(p.relative(uri, from: _rootUrl));
var rawMap = _getSourceMap(module);
if (rawMap == null) return null;
var mapping = (rawMap is String
? source_maps.parse(rawMap)
: source_maps.parseJson(rawMap as Map)) as source_maps.SingleMapping;
mapping.targetUrl = uri;
if (module != "dart_sdk") {
mapping.sourceRoot = p.relative(p.dirname(uri), from: _rootUrl) + '/';
var span = _bundle.spanFor(line, column, files: files, uri: uri);
if (span == null || span.start.sourceUrl == null) return null;
var pathSegments = span.start.sourceUrl.pathSegments;
if (pathSegments.isNotEmpty && pathSegments.last == 'null') return null;
return span;