Expose functionality to compile dart to kernel for the VM (#36598)

packages/flutter_tools/lib/src/codegen.dart

@@ -99,7 +99,6 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
     bool aot = false,
     bool trackWidgetCreation,
     List<String> extraFrontEndOptions,
-    String incrementalCompilerByteStorePath,
     bool targetProductVm = false,
     // These arguments are currently unused.
     String sdkRoot,
@@ -109,6 +108,7 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
     String depFilePath,
     TargetModel targetModel = TargetModel.flutter,
     String initializeFromDill,
+    String platformDill,
   }) async {
     if (fileSystemRoots != null || fileSystemScheme != null || depFilePath != null || targetModel != null || sdkRoot != null || packagesPath != null) {
       printTrace('fileSystemRoots, fileSystemScheme, depFilePath, targetModel,'
@@ -135,7 +135,6 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
       aot: aot,
       trackWidgetCreation: trackWidgetCreation,
       extraFrontEndOptions: extraFrontEndOptions,
-      incrementalCompilerByteStorePath: incrementalCompilerByteStorePath,
       targetProductVm: targetProductVm,
       sdkRoot: sdkRoot,
       packagesPath: PackageMap.globalGeneratedPackagesPath,

packages/flutter_tools/lib/src/compile.dart

@@ -11,12 +11,10 @@ import 'artifacts.dart';
 import 'base/common.dart';
 import 'base/context.dart';
 import 'base/file_system.dart';
-import 'base/fingerprint.dart';
 import 'base/io.dart';
 import 'base/platform.dart';
 import 'base/process_manager.dart';
 import 'base/terminal.dart';
-import 'cache.dart';
 import 'codegen.dart';
 import 'convert.dart';
 import 'dart/package_map.dart';
@@ -51,6 +49,8 @@ class TargetModel {
         return flutter;
       case 'flutter_runner':
         return flutterRunner;
+      case 'vm':
+        return vm;
     }
     assert(false);
     return null;
@@ -64,6 +64,9 @@ class TargetModel {
   /// The fuchsia patched SDK.
   static const TargetModel flutterRunner = TargetModel._('flutter_runner');
 
+  /// The Dart vm.
+  static const TargetModel vm = TargetModel._('vm');
+
   final String _value;
 
   @override
@@ -218,49 +221,20 @@ class KernelCompiler {
     bool aot = false,
     @required bool trackWidgetCreation,
     List<String> extraFrontEndOptions,
-    String incrementalCompilerByteStorePath,
     String packagesPath,
     List<String> fileSystemRoots,
     String fileSystemScheme,
     bool targetProductVm = false,
     String initializeFromDill,
+    String platformDill,
   }) async {
     final String frontendServer = artifacts.getArtifactPath(
       Artifact.frontendServerSnapshotForEngineDartSdk
     );
-    FlutterProject flutterProject;
-    if (fs.file('pubspec.yaml').existsSync()) {
-      flutterProject = FlutterProject.current();
-    }
-
-    // TODO(cbracken): eliminate pathFilter.
-    // Currently the compiler emits buildbot paths for the core libs in the
-    // depfile. None of these are available on the local host.
-    Fingerprinter fingerprinter;
-    if (depFilePath != null) {
-      fingerprinter = Fingerprinter(
-        fingerprintPath: '$depFilePath.fingerprint',
-        paths: <String>[mainPath],
-        properties: <String, String>{
-          'entryPoint': mainPath,
-          'trackWidgetCreation': trackWidgetCreation.toString(),
-          'linkPlatformKernelIn': linkPlatformKernelIn.toString(),
-          'engineHash': Cache.instance.engineRevision,
-          'buildersUsed': '${flutterProject != null && flutterProject.hasBuilders}',
-        },
-        depfilePaths: <String>[depFilePath],
-        pathFilter: (String path) => !path.startsWith('/b/build/slave/'),
-      );
-
-      if (await fingerprinter.doesFingerprintMatch()) {
-        printTrace('Skipping kernel compilation. Fingerprint match.');
-        return CompilerOutput(outputFilePath, 0, /* sources */ null);
-      }
-    }
-
     // This is a URI, not a file path, so the forward slash is correct even on Windows.
-    if (!sdkRoot.endsWith('/'))
+    if (!sdkRoot.endsWith('/')) {
       sdkRoot = '$sdkRoot/';
+    }
     final String engineDartPath = artifacts.getArtifactPath(Artifact.engineDartBinary);
     if (!processManager.canRun(engineDartPath)) {
       throwToolExit('Unable to find Dart binary at $engineDartPath');
@@ -288,9 +262,6 @@ class KernelCompiler {
     } else if (aot) {
       command.add('-Ddart.vm.profile=true');
     }
-    if (incrementalCompilerByteStorePath != null) {
-      command.add('--incremental');
-    }
     Uri mainUri;
     if (packagesPath != null) {
       command.addAll(<String>['--packages', packagesPath]);
@@ -313,6 +284,9 @@ class KernelCompiler {
     if (initializeFromDill != null) {
       command.addAll(<String>['--initialize-from-dill', initializeFromDill]);
     }
+    if (platformDill != null) {
+      command.addAll(<String>[ '--platform', platformDill]);
+    }
 
     if (extraFrontEndOptions != null)
       command.addAll(extraFrontEndOptions);
@@ -337,9 +311,6 @@ class KernelCompiler {
       .listen(_stdoutHandler.handler);
     final int exitCode = await server.exitCode;
     if (exitCode == 0) {
-      if (fingerprinter != null) {
-        await fingerprinter.writeFingerprint();
-      }
       return _stdoutHandler.compilerOutput.future;
     }
     return null;

packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart

@@ -305,6 +305,7 @@ class FakeKernelCompiler implements KernelCompiler {
     List<String> fileSystemRoots,
     String fileSystemScheme,
     bool targetProductVm = false,
+    String platformDill,
     String initializeFromDill}) async {
       fs.file(outputFilePath).createSync(recursive: true);
       return CompilerOutput(outputFilePath, 0, null);

packages/flutter_tools/test/general.shard/compile_test.dart

@@ -505,6 +505,18 @@ example:org-dartlang-app:/
       Platform: _kNoColorTerminalPlatform,
     });
   });
+
+  test('TargetModel values', () {
+    expect(TargetModel('vm'), TargetModel.vm);
+    expect(TargetModel.vm.toString(), 'vm');
+
+    expect(TargetModel('flutter'), TargetModel.flutter);
+    expect(TargetModel.flutter.toString(), 'flutter');
+
+    expect(TargetModel('flutter_runner'), TargetModel.flutterRunner);
+    expect(TargetModel.flutterRunner.toString(), 'flutter_runner');
+    expect(() => TargetModel('foobar'), throwsA(isInstanceOf<AssertionError>()));
+  });
 }
 
 Future<void> _recompile(

packages/flutter_tools/test/general.shard/tester/flutter_tester_test.dart

@@ -167,7 +167,6 @@ Hello!
 
         when(mockKernelCompiler.compile(
           sdkRoot: anyNamed('sdkRoot'),
-          incrementalCompilerByteStorePath: anyNamed('incrementalCompilerByteStorePath'),
           mainPath: anyNamed('mainPath'),
           outputFilePath: anyNamed('outputFilePath'),
           depFilePath: anyNamed('depFilePath'),