Rename MirrorSystem.getName calls in dart2dart.

tests/compiler/dart2js/mirror_helper_test.dart

+// Copyright (c) 2013, 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.
+
+import "package:expect/expect.dart";
+import 'memory_compiler.dart' show compilerFor;
+import '../../../sdk/lib/_internal/compiler/implementation/apiimpl.dart' show
+    Compiler;
+import
+    '../../../sdk/lib/_internal/compiler/implementation/elements/elements.dart'
+show
+    Element, LibraryElement, ClassElement;
+import
+    '../../../sdk/lib/_internal/compiler/implementation/tree/tree.dart'
+show
+    Node;
+import
+    '../../../sdk/lib/_internal/compiler/implementation/dart_backend/dart_backend.dart'
+show
+    DartBackend, ElementAst;
+import
+    '../../../sdk/lib/_internal/compiler/implementation/mirror_renamer/mirror_renamer.dart'
+show
+    MirrorRenamer;
+
+const String MIRROR_HELPER_CLASS = 'MirrorHelper';

[ahe, 2013/08/06 15:53:36]

It's nice that you define constants, but I feel it would be even nicer if you
didn't define them twice :-)

[zarah, 2013/08/08 12:17:10]

Removed! :-)

+const String MIRROR_HELPER_GET_NAME_FUNCTION = 'getName';
+const String MIRROR_HELPER_LIBRARY_NAME = 'mirror_helper.dart';
+const String MIRROR_HELPER_LIBRARY_PREFIX = 'm';
+
+
+main() {
+  testWithMirrorRenaming();
+  testWithoutMirrorRenaming();
+  testWithMirrorRenamingMinify();
+  testWithoutMirrorRenamingMinify();
+}
+
+void testWithMirrorRenaming() {
+  Compiler compiler = compilerFor(
+      MEMORY_SOURCE_FILES,
+      options: ['--output-type=dart']);
+  DartBackend backend = compiler.backend;
+  backend.mirrorHelping = true;

[ahe, 2013/08/06 15:53:36]

I think these four lines are almost always the same. I suggest adding a method
for that (with two named bool parameters to indicate the variable parts).

[zarah, 2013/08/08 12:17:10]

Done.

+  compiler.runCompiler(Uri.parse('memory:main.dart'));
+  Map<Node, String> renames = backend.renames;
+  Map<LibraryElement, String> imports = backend.imports;
+
+  Node getNameFunctionNode =
+      backend.memberNodes.values.first.first.body.statements.nodes.head;

[ahe, 2013/08/06 15:53:36]

This feels a bit brittle to me. How about (not tested):

ClassElement cls = compiler.mainApp.find(const SourceString('Foo'));
FunctionExpression function = cls.localLookup(const
SourceString('noSuchMethod')).parseNode(compiler);
Send getNameFunctionNode = function.body.statements.nodes.toList().single;

[zarah, 2013/08/08 12:17:10]

I agree. The point is however, that in the backend the AST is cloned. Hence, the
node retrieved in your suggestion is not the same as the one in the renames map
and so it doesn't work. 

+
+  Expect.equals(renames[getNameFunctionNode.expression.selector],
+                MIRROR_HELPER_GET_NAME_FUNCTION);
+  Expect.equals(renames[getNameFunctionNode.expression.receiver],
+                '$MIRROR_HELPER_LIBRARY_PREFIX.$MIRROR_HELPER_CLASS');
+  Expect.equals(2, imports.keys.length);
+  Expect.isTrue(imports.keys.any((library) =>
+      library.canonicalUri ==  new Uri(path: MIRROR_HELPER_LIBRARY_NAME)));
+}

[ahe, 2013/08/06 15:53:36]

My comments above apply to the following functions as well.

[zarah, 2013/08/08 12:17:10]

Done.

+
+void testWithMirrorRenamingMinify() {
+  Compiler compiler = compilerFor(
+      MEMORY_SOURCE_FILES,
+      options: ['--output-type=dart', '--minify']);
+  DartBackend backend = compiler.backend;
+  backend.mirrorHelping = true;
+  compiler.runCompiler(Uri.parse('memory:main.dart'));
+  Map<Node, String> renames = backend.renames;
+  Map<LibraryElement, String> imports = backend.imports;
+
+  Node getNameFunctionNode =
+      backend.memberNodes.values.first.first.body.statements.nodes.head;
+
+  Expect.equals(renames[getNameFunctionNode.expression.selector],
+                MIRROR_HELPER_GET_NAME_FUNCTION);
+  Expect.equals(renames[getNameFunctionNode.expression.receiver],
+                '$MIRROR_HELPER_LIBRARY_PREFIX.$MIRROR_HELPER_CLASS');
+  Expect.equals(2, imports.keys.length);
+  Expect.isTrue(imports.keys.any((library) =>
+      library.canonicalUri ==  new Uri(path: MIRROR_HELPER_LIBRARY_NAME)));
+}
+
+void testWithoutMirrorRenaming() {
+  Compiler compiler = compilerFor(
+      MEMORY_SOURCE_FILES,
+      options: ['--output-type=dart']);
+  DartBackend backend = compiler.backend;
+  backend.mirrorHelping = false;
+  compiler.runCompiler(Uri.parse('memory:main.dart'));
+  Map<Node, String> renames = backend.renames;
+  Map<LibraryElement, String> imports = backend.imports;
+
+  Node getNameFunctionNode =
+      backend.memberNodes.values.first.first.body.statements.nodes.head;
+
+  Expect.isFalse(renames.containsKey(getNameFunctionNode.expression.selector));
+  Expect.isFalse(renames.containsKey(getNameFunctionNode.expression.receiver));
+  Expect.equals(1, imports.keys.length);
+}
+
+void testWithoutMirrorRenamingMinify() {
+  Compiler compiler = compilerFor(
+      MEMORY_SOURCE_FILES,
+      options: ['--output-type=dart', '--minify']);
+  DartBackend backend = compiler.backend;
+  backend.mirrorHelping = false;
+  compiler.runCompiler(Uri.parse('memory:main.dart'));
+  Map<Node, String> renames = backend.renames;
+  Map<LibraryElement, String> imports = backend.imports;
+
+  Node getNameFunctionNode =
+      backend.memberNodes.values.first.first.body.statements.nodes.head;
+
+  Expect.isFalse(renames.containsKey(getNameFunctionNode.expression.selector));
+  Expect.isFalse(renames.containsKey(getNameFunctionNode.expression.receiver));
+  Expect.equals(1, imports.keys.length);
+}
+
+const MEMORY_SOURCE_FILES = const <String, String> {
+  'main.dart': """
+import 'dart:mirrors';
+
+
+class Foo {
+  noSuchMethod(Invocation invocation) {
+    MirrorSystem.getName(invocation.memberName);
+  }
+}
+
+void main() {
+  new Foo().fist();
+}
+"""};