Felt analyze (#37481)

* Adding `felt analyze` command that CI will run.

* Remove some copypasta'd stuff.

* Also remove code path from felt.dart that forces a rebuild if it doesn't
detect the host_debug_unopt directory.

* More cleanup of felt.bat for CI.

* Fix typo in felt.bat.

Author: eyebrowsoffire

lib/web_ui/dev/analyze.dart

@@ -0,0 +1,67 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:args/command_runner.dart';
+
+import 'environment.dart';
+import 'pipeline.dart';
+import 'utils.dart';
+
+class AnalyzeCommand extends Command<bool> with ArgUtils<bool> {
+  @override
+  String get name => 'analyze';
+
+  @override
+  String get description => 'Analyze the Flutter web engine.';
+
+  @override
+  FutureOr<bool> run() async {
+    final Pipeline buildPipeline = Pipeline(steps: <PipelineStep>[
+      PubGetStep(),
+      AnalyzeStep(),
+    ]);
+    await buildPipeline.run();
+    return true;
+  }
+}
+
+/// Runs `dart pub get`.
+class PubGetStep extends ProcessStep {
+  @override
+  String get description => 'pub get';
+
+  @override
+  bool get isSafeToInterrupt => true;
+
+  @override
+  Future<ProcessManager> createProcess() {
+    print('Running `dart pub get`...');
+    return startProcess(
+      environment.dartExecutable,
+      <String>['pub', 'get'],
+      workingDirectory: environment.webUiRootDir.path,
+    );
+  }
+}
+
+/// Runs `dart analyze --fatal-infos`.
+class AnalyzeStep extends ProcessStep {
+  @override
+  String get description => 'analyze';
+
+  @override
+  bool get isSafeToInterrupt => true;
+
+  @override
+  Future<ProcessManager> createProcess() {
+    print('Running `dart analyze`...');
+    return startProcess(
+      environment.dartExecutable,
+      <String>['analyze', '--fatal-infos'],
+      workingDirectory: environment.webUiRootDir.path,
+    );
+  }
+}

lib/web_ui/dev/felt.bat

@@ -35,38 +35,21 @@ IF NOT DEFINED DART_SDK_DIR (
 )
 SET DART_BIN=%DART_SDK_DIR%\bin\dart
 
-SET needsHostDebugUnoptRebuild=0
-for %%x in (%*) do (
-  if ["%%~x"]==["--clean"] (
-    ECHO Clean rebuild requested
-    SET needsHostDebugUnoptRebuild=1
-  )
-)
-
-IF NOT EXIST %OUT_DIR% (SET needsHostDebugUnoptRebuild=1)
-IF NOT EXIST %HOST_DEBUG_UNOPT_DIR% (SET needsHostDebugUnoptRebuild=1)
-
-IF %needsHostDebugUnoptRebuild%==1 (
-  ECHO Building host_debug_unopt
-  :: Delete old snapshot, if any, because the new Dart SDK may invalidate it.
-  IF EXIST "%SNAPSHOT_PATH%" (
-    del %SNAPSHOT_PATH%
-  )
-  CALL gclient sync -D
-  CALL python %GN% --unoptimized --full-dart-sdk
-  CALL ninja -C %HOST_DEBUG_UNOPT_DIR%)
-
 cd %WEB_UI_DIR%
-IF NOT EXIST "%SNAPSHOT_PATH%" (
-  ECHO Precompiling felt snapshot
-  CALL %DART_SDK_DIR%\bin\dart pub get
-  %DART_BIN% --snapshot="%SNAPSHOT_PATH%" --packages="%WEB_UI_DIR%\.dart_tool\package_config.json" %FELT_PATH%
-)
 
-IF "%1"=="test" (
-  %DART_SDK_DIR%\bin\dart --packages="%WEB_UI_DIR%\.dart_tool\package_config.json" "%SNAPSHOT_PATH%" %* --browser=chrome
+IF FELT_USE_SNAPSHOT=="0" (
+  ECHO Invoking felt.dart without snapshot
+  SET FELT_TARGET=%FELT_PATH%
 ) ELSE (
-  %DART_SDK_DIR%\bin\dart --packages="%WEB_UI_DIR%\.dart_tool\package_config.json" "%SNAPSHOT_PATH%" %*
+  IF NOT EXIST "%SNAPSHOT_PATH%" (
+    ECHO Precompiling felt snapshot
+    CALL %DART_BIN% pub get
+    %DART_BIN% --snapshot="%SNAPSHOT_PATH%" --packages="%WEB_UI_DIR%\.dart_tool\package_config.json" %FELT_PATH%
+  )
+  SET FELT_TARGET=%SNAPSHOT_PATH%
+  ECHO Invoking felt snapshot
 )
 
+%DART_BIN% --packages="%WEB_UI_DIR%\.dart_tool\package_config.json" "%FELT_TARGET%" %*
+
 EXIT /B %ERRORLEVEL%

lib/web_ui/dev/felt.dart

@@ -6,6 +6,7 @@ import 'dart:io' as io;
 
 import 'package:args/command_runner.dart';
 
+import 'analyze.dart';
 import 'build.dart';
 import 'clean.dart';
 import 'exceptions.dart';
@@ -19,6 +20,7 @@ CommandRunner<bool> runner = CommandRunner<bool>(
   'felt',
   'Command-line utility for building and testing Flutter web engine.',
 )
+  ..addCommand(AnalyzeCommand())
   ..addCommand(BuildCommand())
   ..addCommand(CleanCommand())
   ..addCommand(GenerateFallbackFontDataCommand())