Train frontend_server snapshot (flutter#4560)

Reland 86430be with a fix for Windows build Cuts 30% from hot-reload benchmarks with `--preview-dart-2`
paulyc · Jan 17, 2018 · 6de9931 · 6de9931
1 parent 7173a15
commit 6de9931
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Showing 3 changed files with 20 additions and 3 deletions.
diff --git a/frontend_server/BUILD.gn b/frontend_server/BUILD.gn
@@ -6,8 +6,12 @@ import("//third_party/dart/utils/application_snapshot.gni")
 
 application_snapshot("frontend_server") {
   main_dart = "bin/starter.dart"
+  deps = [
+    "$flutter_root/lib/snapshot:kernel_platform_files",
+  ]
   dot_packages = rebase_path(".packages")
-  training_args = [ "--train" ]
+  flutter_patched_sdk = rebase_path("$root_out_dir/flutter_patched_sdk")
+  training_args = [ "--train", "--sdk-root=$flutter_patched_sdk" ]
 
   frontend_server_files = exec_script("//third_party/dart/tools/list_dart_files.py",
      [ "absolute", rebase_path("."), ], "list lines")

diff --git a/frontend_server/lib/server.dart b/frontend_server/lib/server.dart
@@ -261,6 +261,17 @@ Future<int> starter(
   }
 
   if (options['train']) {
+    final String sdkRoot = options['sdk-root'];
+    options = _argParser.parse(<String>['--incremental', '--sdk-root=$sdkRoot']);
+    compiler ??= new _FrontendCompiler(output, printerFactory: binaryPrinterFactory);
+    await compiler.compile(Platform.script.toFilePath(), options, generator: generator);
+    compiler.acceptLastDelta();
+    await compiler.recompileDelta();
+    compiler.acceptLastDelta();
+    await compiler.recompileDelta();
+    compiler.acceptLastDelta();
+    await compiler.recompileDelta();
+    compiler.acceptLastDelta();
     return 0;
   }
 

diff --git a/frontend_server/test/server_test.dart b/frontend_server/test/server_test.dart
@@ -26,8 +26,10 @@ class _MockedBinaryPrinter extends Mock implements BinaryPrinter {}
 
 Future<int> main() async {
   group('basic', () {
-    test('train completes', () async {
-      expect(await starter(<String>['--train']), equals(0));
+    final CompilerInterface compiler = new _MockedCompiler();
+
+    test('train with mocked compiler completes', () async {
+      expect(await starter(<String>['--train'], compiler: compiler), equals(0));
     });
   });