Avoid inlining constants that are used via a deferred import.

tests/compiler/dart2js/deferred_dont_inline_deferred_constants_test.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.
+
+// Test that the additional runtime type support is output to the right
+// Files when using deferred loading.
+
+import 'package:expect/expect.dart';
+import "package:async_helper/async_helper.dart";
+import 'memory_source_file_helper.dart';
+import "dart:async";
+
+import '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart'
+       as dart2js;
+
+class MemoryOutputSink extends EventSink<String> {
+  StringBuffer mem = new StringBuffer();
+  void add(String event) {
+    mem.write(event);
+  }
+  void addError(String event, [StackTrace stackTrace]) {
+    Expect.isTrue(false);
+  }
+  void close() {}
+}
+
+void main() {
+  Uri script = currentDirectory.resolveUri(Platform.script);
+  Uri libraryRoot = script.resolve('../../../sdk/');
+  Uri packageRoot = script.resolve('./packages/');
+
+  var provider = new MemorySourceFileProvider(MEMORY_SOURCE_FILES);
+  var handler = new FormattingDiagnosticHandler(provider);
+
+  Map<String, MemoryOutputSink> outputs = new Map<String, MemoryOutputSink>();
+
+  MemoryOutputSink outputSaver(name, extension) {
+    if (name == '') {
+      name = 'main';
+    }
+    return outputs.putIfAbsent("$name.$extension", () {
+      return new MemoryOutputSink();
+    });
+  }
+
+  Compiler compiler = new Compiler(provider.readStringFromUri,
+                                   outputSaver,
+                                   handler.diagnosticHandler,
+                                   libraryRoot,
+                                   packageRoot,
+                                   [],
+                                   {});
+  asyncTest(() => compiler.run(Uri.parse('memory:main.dart')).then((_) {
+    String mainOutput = outputs['main.js'].mem.toString();
+    String lib1Output = outputs['out_lib1.part.js'].mem.toString();
+    String lib2Output = outputs['out_lib2.part.js'].mem.toString();
+    String lib12Output = outputs['out_lib1_lib2.part.js'].mem.toString();
+    // Test that the deferred constants are not inlined into the main file.
+    RegExp re1 = new RegExp(r"= .string1");
+    RegExp re2 = new RegExp(r"= .string2");
+    RegExp re3 = new RegExp(r"= 1010");
+    Expect.isTrue(re1.hasMatch(lib1Output));
+    Expect.isTrue(re2.hasMatch(lib1Output));
+    Expect.isTrue(re3.hasMatch(lib1Output));
+    Expect.isFalse(re1.hasMatch(mainOutput));
+    Expect.isFalse(re2.hasMatch(mainOutput));
+    Expect.isFalse(re3.hasMatch(mainOutput));
+    // Test that the non-deferred constant is inlined.
+    Expect.isTrue(new RegExp(r"print\(.string3.\)").hasMatch(mainOutput));
+    Expect.isFalse(new RegExp(r"= .string3").hasMatch(mainOutput));
+    Expect.isTrue(new RegExp(r"print\(.string4.\)").hasMatch(mainOutput));
+
+    // C(1) is shared between main, lib1 and lib2. Test that lib1 and lib2 each
+    // has a reference to it. It is defined in the main output file.
+    Expect.isTrue(new RegExp(r"C.C_1 =").hasMatch(mainOutput));
+    Expect.isFalse(new RegExp(r"= C.C_1").hasMatch(mainOutput));
+
+    Expect.isTrue(new RegExp(r"= C.C_1").hasMatch(lib1Output));
+    Expect.isTrue(new RegExp(r"= C.C_1").hasMatch(lib2Output));
+
+    // C(2) is shared between lib1 and lib2, each of them has their own
+    // reference to it.
+    Expect.isFalse(new RegExp(r"= C.C_2").hasMatch(mainOutput));
+
+    Expect.isTrue(new RegExp(r"= C.C_2").hasMatch(lib1Output));
+    Expect.isTrue(new RegExp(r"= C.C_2").hasMatch(lib2Output));
+    Expect.isTrue(new RegExp(r"C.C_2 =").hasMatch(lib12Output));
+
+    // "string4" is shared between lib1 and lib2, but it can be inlined.
+    Expect.isTrue(new RegExp(r"= .string4").hasMatch(lib1Output));
+    Expect.isTrue(new RegExp(r"= .string4").hasMatch(lib2Output));
+    Expect.isFalse(new RegExp(r"= .string4").hasMatch(lib12Output));
+  }));
+}
+
+// Make sure that deferred constants are not inlined into the main hunk.
+const Map MEMORY_SOURCE_FILES = const {"main.dart": """
+import "dart:async";
+
+import 'lib1.dart' deferred as lib1;
+import 'lib2.dart' deferred as lib2;
+
+const c = "string3";
+
+class C {
+  final p;
+  const C(this.p);
+}
+
+void main() {
+  lib1.loadLibrary().then((_) {
+    lib2.loadLibrary().then((_) {
+      print(lib1.C1);
+      print(lib1.C2);
+      print(lib1.C.C3);
+      print(c);
+      print(lib1.C4);
+      print(lib2.C4);
+      print(lib1.C5);
+      print(lib2.C5);
+      print(lib1.C6);
+      print(lib2.C6);
+      print("string4");
+      print(const C(1));
+    });
+  });
+}
+""", "lib1.dart": """
+import "main.dart" as main;
+const C1 = "string1";
+const C2 = 1010;
+class C {
+  static const C3 = "string2";
+}
+const C4 = "string4";
+const C5 = const main.C(1);
+const C6 = const main.C(2);
+""", "lib2.dart": """
+import "main.dart" as main;
+const C4 = "string4";
+const C5 = const main.C(1);
+const C6 = const main.C(2);
+"""};