Add MultiSourceInformationStrategy

pkg/compiler/lib/src/js_emitter/full_emitter/emitter.dart

 // Copyright (c) 2014, 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 dart2js.js_emitter.full_emitter;
 
 import 'dart:collection' show HashMap;
 import 'dart:convert';
 
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
@@ skipping 1522 matching lines @@
     outputBuffers[mainOutputUnit] = mainOutput;
 
     mainOutput.addBuffer(jsAst.createCodeBuffer(program, compiler,
         monitor: compiler.dumpInfoTask));
 
     if (compiler.options.deferredMapUri != null) {
       outputDeferredMap();
     }
 
     if (generateSourceMap) {
-      mainOutput.add(generateSourceMapTag(
+      mainOutput.add(SourceMapBuilder.generateSourceMapTag(
           compiler.options.sourceMapUri, compiler.options.outputUri));
     }
 
     mainOutput.close();
 
     if (generateSourceMap) {
-      outputSourceMap(mainOutput, lineColumnCollector, '',
-          compiler.options.sourceMapUri, compiler.options.outputUri);
+      SourceMapBuilder.outputSourceMap(
+          mainOutput,
+          lineColumnCollector,
+          '',
+          compiler.options.sourceMapUri,
+          compiler.options.outputUri,
+          compiler.outputProvider);
     }
   }
 
   Map<OutputUnit, jsAst.Expression> buildDescriptorsForOutputUnits(
       Program program) {
     Map<OutputUnit, jsAst.Expression> outputs =
         new Map<OutputUnit, jsAst.Expression>();
 
     for (Fragment fragment in program.deferredFragments) {
       OutputUnit outputUnit = fragment.outputUnit;
@@ skipping 70 matching lines @@
     });
     emitMainOutputUnit(program.mainFragment.outputUnit, mainOutput);
 
     if (backend.requiresPreamble && !backend.htmlLibraryIsLoaded) {
       reporter.reportHintMessage(NO_LOCATION_SPANNABLE, MessageKind.PREAMBLE);
     }
     // Return the total program size.
     return outputBuffers.values.fold(0, (a, b) => a + b.length);
   }
 
-  String generateSourceMapTag(Uri sourceMapUri, Uri fileUri) {
-    if (sourceMapUri != null && fileUri != null) {
-      String sourceMapFileName = relativize(fileUri, sourceMapUri, false);
-      return '''
-
-//# sourceMappingURL=$sourceMapFileName
-''';
-    }
-    return '';
-  }
-
   ClassBuilder getElementDescriptor(Element element, Fragment fragment) {
     Element owner = element.library;
     if (!element.isLibrary &&
         !element.isTopLevel &&
         !backend.isNative(element)) {
       // For static (not top level) elements, record their code in a buffer
       // specific to the class. For now, not supported for native classes and
       // native elements.
       ClassElement cls = element.enclosingClassOrCompilationUnit.declaration;
       if (compiler.codegenWorldBuilder.directlyInstantiatedClasses
@@ skipping 228 matching lines @@
         }
 
         if (outputUri != null) {
           String partFileName = partName + ".js";
           List<String> partSegments = outputUri.pathSegments.toList();
           partSegments[partSegments.length - 1] = partFileName;
           partUri =
               compiler.options.outputUri.replace(pathSegments: partSegments);
         }
 
-        output.add(generateSourceMapTag(mapUri, partUri));
+        output.add(SourceMapBuilder.generateSourceMapTag(mapUri, partUri));
         output.close();
-        outputSourceMap(output, lineColumnCollector, partName, mapUri, partUri);
+        SourceMapBuilder.outputSourceMap(output, lineColumnCollector, partName,
+            mapUri, partUri, compiler.outputProvider);
       } else {
         output.close();
       }
 
       hunkHashes[outputUnit] = hash;
     }
     return hunkHashes;
   }
 
   jsAst.Comment buildGeneratedBy() {
     List<String> options = [];
     if (compiler.commonElements.mirrorsLibrary != null) options.add('mirrors');
     if (compiler.options.useContentSecurityPolicy) options.add("CSP");
     return new jsAst.Comment(generatedBy(compiler, flavor: options.join(", ")));
   }
 
-  void outputSourceMap(
-      CodeOutput output, LineColumnProvider lineColumnProvider, String name,
-      [Uri sourceMapUri, Uri fileUri]) {
-    if (!generateSourceMap) return;
-    // Create a source file for the compilation output. This allows using
-    // [:getLine:] to transform offsets to line numbers in [SourceMapBuilder].
-    SourceMapBuilder sourceMapBuilder =
-        new SourceMapBuilder(sourceMapUri, fileUri, lineColumnProvider);
-    output.forEachSourceLocation(sourceMapBuilder.addMapping);
-    String sourceMap = sourceMapBuilder.build();
-    compiler.outputProvider(name, 'js.map', OutputType.js_map)
-      ..add(sourceMap)
-      ..close();
-  }
-
   void outputDeferredMap() {
     Map<String, dynamic> mapping = new Map<String, dynamic>();
     // Json does not support comments, so we embed the explanation in the
     // data.
     mapping["_comment"] = "This mapping shows which compiled `.js` files are "
         "needed for a given deferred library import.";
     mapping.addAll(compiler.deferredLoadTask.computeDeferredMap());
     compiler.outputProvider(
         compiler.options.deferredMapUri.path, '', OutputType.info)
       ..add(const JsonEncoder.withIndent("  ").convert(mapping))
       ..close();
   }
 }