sort errors so they appear in stable order

lib/src/compiler.dart

 // Copyright (c) 2015, 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.
 
 /// Command line tool to run the checker on a Dart program.
 library dev_compiler.src.compiler;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:math' as math;
@@ skipping 66 matching lines @@
   String _runtimeOutputDir;
 
   /// Already compiled sources, so we don't compile them again.
   final _compiled = new HashSet<LibraryElement>();
 
   bool _failure = false;
   bool get failure => _failure;
 
   BatchCompiler(AnalysisContext context, CompilerOptions options,
       {AnalysisErrorListener reporter})
-      : super(context, options, reporter) {
+      : super(
+            context,
+            options,
+            new ErrorCollector(
+                reporter ?? AnalysisErrorListener.NULL_LISTENER)) {
     _inputBaseDir = options.inputBaseDir;
     if (outputDir != null) {
       _jsGen = new JSGenerator(this);
       _runtimeOutputDir = path.join(outputDir, 'dev_compiler', 'runtime');
     }
     _dartCore = context.typeProvider.objectType.element.library;
   }
 
+  ErrorCollector get reporter => checker.reporter;
+
   void reset() {
     _compiled.clear();
   }
 
   /// Compiles every file in [options.inputs].
   /// Returns true on successful compile.
   bool run() {
     var clock = new Stopwatch()..start();
     options.inputs.forEach(compileFromUriString);
     clock.stop();
@@ skipping 14 matching lines @@
     var source = context.sourceFactory.forUri(Uri.encodeFull('$uri'));
     if (source == null) {
       throw new ArgumentError.value('$uri', 'uri', 'could not find source for');
     }
     compileSource(source);
   }
 
   void compileSource(Source source) {
     if (AnalysisEngine.isHtmlFileName(source.uri.path)) {
       _compileHtml(source);
-      return;
+    } else {
+      _compileLibrary(context.computeLibraryElement(source));
     }
-    compileLibrary(context.computeLibraryElement(source));
+    reporter.flush();
   }
 
-  void compileLibrary(LibraryElement library) {
+  void _compileLibrary(LibraryElement library) {
     if (!_compiled.add(library)) return;
 
     if (!options.checkSdk && library.source.uri.scheme == 'dart') {
       if (_jsGen != null) _copyDartRuntime();
       return;
     }
 
     // TODO(jmesserly): in incremental mode, we can skip the transitive
     // compile of imports/exports.
-    compileLibrary(_dartCore); // implicit dart:core dependency
-    library.importedLibraries.forEach(compileLibrary);
-    library.exportedLibraries.forEach(compileLibrary);
+    _compileLibrary(_dartCore); // implicit dart:core dependency
+    library.importedLibraries.forEach(_compileLibrary);
+    library.exportedLibraries.forEach(_compileLibrary);
 
     var unitElements = [library.definingCompilationUnit]..addAll(library.parts);
     var units = <CompilationUnit>[];
 
     bool failureInLib = false;
     for (var element in unitElements) {
       var unit = context.resolveCompilationUnit(element.source, library);
       units.add(unit);
       failureInLib = logErrors(element.source) || failureInLib;
       checker.visitCompilationUnit(unit);
@@ skipping 44 matching lines @@
             }
           }
           scriptSource = new DartScript(source, fragments);
         }
       } else if (AnalysisEngine.isDartFileName(srcAttr)) {
         scriptSource = context.sourceFactory.resolveUri(source, srcAttr);
       }
 
       if (scriptSource != null) {
         var lib = context.computeLibraryElement(scriptSource);
-        compileLibrary(lib);
+        _compileLibrary(lib);
         script.replaceWith(_linkLibraries(lib, loadedLibs, from: htmlOutDir));
       }
     }
 
     new File(getOutputPath(source.uri)).openSync(mode: FileMode.WRITE)
       ..writeStringSync(document.outerHtml)
       ..writeStringSync('\n')
       ..closeSync();
   }
 
@@ skipping 42 matching lines @@
 abstract class AbstractCompiler {
   final CompilerOptions options;
   final AnalysisContext context;
   final CodeChecker checker;
 
   AbstractCompiler(AnalysisContext context, CompilerOptions options,
       [AnalysisErrorListener reporter])
       : context = context,
         options = options,
         checker = createChecker(context.typeProvider, options.strongOptions,
-            reporter == null ? AnalysisErrorListener.NULL_LISTENER : reporter) {
+            reporter ?? AnalysisErrorListener.NULL_LISTENER) {
     enableDevCompilerInference(context, options.strongOptions);
   }
 
   static CodeChecker createChecker(TypeProvider typeProvider,
       StrongModeOptions options, AnalysisErrorListener reporter) {
     return new CodeChecker(
         new RestrictedRules(typeProvider, options: options), reporter, options);
   }
 
   String get outputDir => options.codegenOptions.outputDir;
@@ skipping 153 matching lines @@
     '_rtti.js',
     '_classes.js',
     '_operations.js',
     'dart_runtime.js',
   ];
   files.addAll(corelibOrder.map((l) => l.replaceAll('.', '/') + '.js'));
   return files;
 }();
 
 final _log = new Logger('dev_compiler.src.compiler');