Use deferred loading for message catalogs.

pkg/intl/test/message_extraction/message_extraction_test.dart

Index: pkg/intl/test/message_extraction/message_extraction_test.dart
diff --git a/pkg/intl/test/message_extraction/message_extraction_test.dart b/pkg/intl/test/message_extraction/message_extraction_test.dart
index 0402765784041f628e970f88f02ec593b16d4256..14987ec091038f511e7a980abb40e72280cc50c3 100644
--- a/pkg/intl/test/message_extraction/message_extraction_test.dart
+++ b/pkg/intl/test/message_extraction/message_extraction_test.dart
@@ -16,8 +16,12 @@ final dart = Platform.executable;
 /** The VM arguments we were given, most important package-root. */
 final vmArgs = Platform.executableArguments;
 
-var tempDir = Directory.systemTemp.createTempSync('message_extraction_test'
-    ).path;
+String get tempDir => _tempDir == null ? _tempDir = _createTempDir() : _tempDir;

[Emily Fortuna, 2014/05/15 19:24:36]

can you put a brief comment above this section here similar to the lines 49-51
explaining what these functions are?

[Alan Knight, 2014/05/15 20:02:18]

Done.

+var _tempDir;
+_createTempDir() => useLocalDirectory ? '.' :
+  Directory.systemTemp.createTempSync('message_extraction_test').path;
+
+var useLocalDirectory = false;
 
 /**
  * Translate a relative file path into this test directory. This is
@@ -41,7 +45,14 @@ String asTempDirPath([String s]) {
   return path.join(tempDir, s);
 }
 
-main() {
+main(arguments) {
+  // If debugging, use --local to avoid copying everything to temporary
+  // directories to make it even harder to debug. Note that this will also
+  // not delete the generated files, so may require manual cleanup.
+  if (arguments.contains("--local")) {
+    print("Testing using local directory for generated files");
+    useLocalDirectory = true;
+  }
   setUp(copyFilesToTempDirectory);
   test("Test round trip message extraction, translation, code generation, "
       "and printing", () {
@@ -56,6 +67,7 @@ main() {
 }
 
 void copyFilesToTempDirectory() {
+  if (useLocalDirectory) return;
   var files = [asTestDirPath('sample_with_messages.dart'),
       asTestDirPath('part_of_sample_with_messages.dart'),
       asTestDirPath('verify_messages.dart'),
@@ -68,6 +80,7 @@ void copyFilesToTempDirectory() {
 }
 
 void deleteGeneratedFiles() {
+  if (useLocalDirectory) return;
   try {
     var dir = new Directory(tempDir);
     dir.listSync().forEach((x) => x.deleteSync());