Package map processing abstraction.

pkg/analyzer/test/src/context/context_factory_test.dart

+// Copyright (c) 2016, 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 analyzer.test.src.context.context_factory_test;
+
+import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/file_system/memory_file_system.dart';
+import 'package:analyzer/src/context/context_factory.dart';
+import 'package:unittest/unittest.dart';
+
+import '../../utils.dart';
+
+main() {
+  initializeTestEnvironment();
+
+  group('PackageMapProcessor', () {

[Brian Wilkerson, 2016/06/07 20:48:48]

There are a lot of cases not tested here.
- What if the package map is empty?
- What if the package map doesn't have a package with an embedder file?
- What is there is no package with an ext?
- What if we don't find either one?
- What happens if one or both of those files are invalid?

Those are just the ones that come to mind quickly, you can probably think of
others.

(Also, it would be really nice to use reflectiveTest because it's much easier to
find the tests when there's a failure.)

[pquitslund, 2016/06/07 20:59:58]

Your wish is my command. :)  Done!

+    MemoryResourceProvider resourceProvider = new MemoryResourceProvider();
+
+    Folder empty = resourceProvider.newFolder('/empty');
+    Folder tmp_sdk_ext = resourceProvider.newFolder('/tmp_sdk_ext');
+    Folder tmp_embedder = resourceProvider.newFolder('/tmp_embedder');
+
+    Map<String, List<Folder>> packageMap = <String, List<Folder>>{
+      'empty': [empty],
+      'tmp_embedder': [tmp_embedder],
+      'tmp_sdk_ext': [tmp_sdk_ext]
+    };
+
+    test('basic processing', () {
+      resourceProvider.newFile(
+          '/tmp_sdk_ext/_sdkext',
+          r'''
+  {
+    "dart:ui": "ui.dart"
+  }''');
+      resourceProvider.newFile(
+          '/tmp_embedder/_embedder.yaml',
+          r'''
+embedded_libs:
+  "dart:core" : "core.dart"
+  "dart:fox": "slippy.dart"
+  "dart:bear": "grizzly.dart"
+  "dart:relative": "../relative.dart"
+  "dart:deep": "deep/directory/file.dart"
+''');
+
+      PackageMapProcessor proc = new PackageMapProcessor(packageMap);
+      expect(proc.embeddedLibraries.size(), 5);
+      expect(proc.extendedLibraries.size(), 1);

[Brian Wilkerson, 2016/06/07 20:48:48]

We should test that the library map has the right mapping for at least one
library from each source.

[pquitslund, 2016/06/07 20:59:58]

Agreed.  I'll follow up with a test-full follow up CL.

+    });
+    test('extenders do not override', () {
+      resourceProvider.newFile(
+          '/tmp_sdk_ext/_sdkext',
+          r'''
+  {
+    "dart:ui": "ui2.dart"
+  }''');
+      resourceProvider.newFile(
+          '/tmp_embedder/_embedder.yaml',
+          r'''
+embedded_libs:
+  "dart:core" : "core.dart"
+  "dart:ui": "ui.dart"
+''');
+
+      PackageMapProcessor proc = new PackageMapProcessor(packageMap);
+      expect(proc.embeddedLibraries.size(), 2);
+      expect(proc.extendedLibraries.size(), 1);
+      expect(proc.libraryMap.size(), 2);
+      expect(
+          proc.libraryMap.getLibrary('dart:ui').path, '/tmp_embedder/ui.dart');
+    });
+  });
+}