Add support for 'dart.library.X' environment variables in dart2js.

tests/compiler/dart2js/library_env_test.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.
+
+/// Check that 'dart:' libraries have their corresponding dart.library.X
+/// environment variable set.
+
+import "dart:io";
+
+import "dart:async";
+
+import "memory_source_file_helper.dart";
+
+import "package:async_helper/async_helper.dart";
+
+import 'package:expect/expect.dart' show
+    Expect;
+
+import 'package:compiler/src/elements/elements.dart' show
+    LibraryElement;
+
+import 'package:compiler/src/null_compiler_output.dart' show
+    NullCompilerOutput;
+
+import 'package:compiler/compiler_new.dart' show
+    CompilerInput,
+    CompilerDiagnostics;
+
+import 'package:sdk_library_metadata/libraries.dart' show
+    LibraryInfo;
+
+const clientPlatform = r'''
+[dart-spec]
+spec: 3rd edition.
+
+[features]
+# No extra features
+
+[libraries]
+mock.client: mock1.dart
+mock.shared: mock3.dart
+collection: collection/collection.dart
+html: html/dart2js/html_dart2js.dart
+''';
+
+const serverPlatform = r'''
+[dart-spec]
+spec: 3rd edition.
+
+[features]
+# No extra features
+
+[libraries]
+mock.server: mock2.dart
+mock.shared: mock3.dart
+collection: collection/collection.dart
+io: io/io.dart
+''';
+
+class DummyCompilerInput implements CompilerInput {
+  const DummyCompilerInput();
+
+  readFromUri(uri) async {
+    if (uri.toString().endsWith("dart_client.platform")) {
+      return clientPlatform;
+    } else if (uri.toString().endsWith("dart_server.platform")) {
+      return serverPlatform;
+    } else {
+      throw "should not be needed $uri";
+    }
+  }
+}
+
+class DummyCompilerDiagnostics implements CompilerDiagnostics {
+  const DummyCompilerDiagnostics();
+
+  report(code, uri, begin, end, text, kind) {
+    throw "should not be needed";
+  }
+}
+
+class CustomCompiler extends CompilerImpl {
+  CustomCompiler(
+      options,
+      environment)
+      : super(
+          const DummyCompilerInput(),
+          const NullCompilerOutput(),
+          const DummyCompilerDiagnostics(),
+          Uri.base.resolve("sdk/"),
+          null,
+          options,
+          environment);
+}
+
+runTest() async {
+  var compiler = new CustomCompiler(
+      [],
+      {});
+
+  await compiler.setupSdk();
+
+  // Core libraries are always present.
+  Expect.equals("true", compiler.fromEnvironment("dart.library.collection"));
+  // Non-existing entries in the environment return 'null'.
+  Expect.isNull(compiler.fromEnvironment("not in env"));
+  // Check for client libraries (default if there are no flags to the compiler).
+  Expect.equals("true", compiler.fromEnvironment("dart.library.mock.client"));
+  Expect.equals("true", compiler.fromEnvironment("dart.library.html"));
+  // Check for shared libraries..
+  Expect.equals("true", compiler.fromEnvironment("dart.library.mock.shared"));
+  // Check server libraries are not present.
+  Expect.equals(null, compiler.fromEnvironment("dart.library.mock.server"));
+  Expect.equals(null, compiler.fromEnvironment("dart.library.io"));
+
+  compiler = new CustomCompiler(
+      ['--categories=Server'],
+      {});
+
+  await compiler.setupSdk();
+
+  // Core libraries are always present.
+  Expect.equals("true", compiler.fromEnvironment("dart.library.collection"));
+  // Non-existing entries in the environment return 'null'.
+  Expect.isNull(compiler.fromEnvironment("not in env"));
+  // Check client libraries are not present.
+  Expect.equals(null, compiler.fromEnvironment("dart.library.mock.client"));
+  Expect.equals(null, compiler.fromEnvironment("dart.library.html"));
+  // Check for shared libraries..
+  Expect.equals("true", compiler.fromEnvironment("dart.library.mock.shared"));
+  // Check for server libraries.
+  Expect.equals("true", compiler.fromEnvironment("dart.library.mock.server"));
+  Expect.equals("true", compiler.fromEnvironment("dart.library.io"));
+
+  // Check that user-defined env-variables win.
+  compiler = new CustomCompiler(
+      [],
+      {'dart.library.collection': "false",
+       'dart.library.mock.client': "foo"});
+
+  await compiler.setupSdk();
+
+  Expect.equals("false", compiler.fromEnvironment("dart.library.collection"));
+  Expect.equals("foo", compiler.fromEnvironment("dart.library.mock.client"));
+}
+
+main() {
+  asyncStart();
+  runTest().then((_) {
+    asyncEnd();
+  });
+}