Add sass task

Author: aaronlademann-wf

.gitignore

@@ -28,4 +28,6 @@ test_reports/
 /test_fixtures/dart_x_only/doc/api/
 /test_fixtures/docs/docs/doc/api/
 /test_fixtures/format/changes_needed_temp/
-/test_fixtures/needs_build_runner/.dart_tool
+/test_fixtures/needs_build_runner/.dart_tool
+/test_fixtures/sass/fake_consumer_package
+/test_fixtures/coverage/functional_test/pubspec.lock

README.md

@@ -27,6 +27,7 @@ development requirements:
 - Consistent code formatting
 - Static analysis to detect issues
 - Documentation generation
+- CSS generation using the Dart Sass compiler
 - Examples for manual testing/exploration
 - Applying a LICENSE file to all source files
 - Running dart unit tests on Sauce Labs
@@ -85,6 +86,7 @@ local tasks.
 - **Coverage:** collects coverage over test suites (unit, integration, and functional) and generates a report. Uses the [`coverage` package](https://github.com/dart-lang/coverage).
 - **Code Formatting:** runs the [`dartfmt` tool from the `dart_style` package](https://github.com/dart-lang/dart_style) over source code.
 - **Static Analysis:** runs the [`dartanalyzer`](https://www.dartlang.org/tools/analyzer/) over source code.
+- **Compiling Sass:** runs the [`compile_sass` tool from the `w_common` package](https://github.com/workiva/w_common).
 - **Applying a License to Source Files:** copies a LICENSE file to all applicable files.
 - **Generate a test runner file:** that allows for faster test execution.
 - **Running dart unit tests on Sauce Labs:** compiles dart unit tests that can be run in the browser and executes them on various platforms using Sauce Labs.
@@ -240,6 +242,7 @@ ddev format
 ddev gen-test-runner
 ddev task-runner
 ddev test
+ddev sass
 
 # without the alias
 pub run dart_dev analyze
@@ -249,6 +252,7 @@ pub run dart_dev format
 pub run dart_dev gen-test-runner
 pub run dart_dev task-runner
 pub run dart_dev test
+pub run dart_dev sass
 ```
 
 Add the `-h` flag to any of the above commands to receive additional help

bin/compile_sass_proxy.dart

@@ -0,0 +1,41 @@
+// Copyright 2019 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// A proxy for the `compile_sass` executable from w_common.
+///
+/// Present so that dart_dev consumers do not have to have a direct dependency
+/// on w_common in order to run `pub run dart_dev sass`.
+///
+/// __Do not run directly - run `pub run dart_dev sass` instead.__
+library dart_dev.bin.compile_sass_proxy;
+
+import 'dart:io';
+
+import 'package:dart_dev/src/tasks/sass/api.dart'
+    show intentionalInternalProxyArg;
+import 'package:dart_dev/util.dart' show reporter;
+import 'package:w_common/sass.dart' as wc_compile_sass;
+
+main(List<String> args) async {
+  if (!args.contains(intentionalInternalProxyArg)) {
+    exitCode = 1;
+    reporter.error(
+        '[UNSUPPORTED]: Do not run `pub run dart_dev compile_sass_proxy` directly.\n\n'
+        'Run `pub run dart_dev sass` instead.');
+    return;
+  }
+
+  args.remove(intentionalInternalProxyArg);
+  await wc_compile_sass.main(args);
+}

lib/src/dart_dev_cli.dart

@@ -18,6 +18,7 @@ import 'dart:async';
 import 'dart:io';
 
 import 'package:args/args.dart';
+import 'package:dart_dev/src/tasks/sass/cli.dart';
 import 'package:dart_dev/util.dart' show reporter;
 
 import 'package:dart_dev/src/tasks/cli.dart';
@@ -63,6 +64,7 @@ dev(List<String> args) async {
   registerTask(new InitCli(), config.init);
   registerTask(new TaskRunnerCli(), config.taskRunner);
   registerTask(new TestCli(), config.test);
+  registerTask(new SassCli(), config.sass);
 
   try {
     LocalCli.discover(config.local.taskPaths).forEach((task, exec) {

lib/src/tasks/config.dart

@@ -22,6 +22,7 @@ import 'package:dart_dev/src/tasks/dart_x_only/config.dart';
 import 'package:dart_dev/src/tasks/format/config.dart';
 import 'package:dart_dev/src/tasks/gen_test_runner/config.dart';
 import 'package:dart_dev/src/tasks/init/config.dart';
+import 'package:dart_dev/src/tasks/sass/config.dart';
 import 'package:dart_dev/src/tasks/task_runner/config.dart';
 import 'package:dart_dev/src/tasks/test/config.dart';
 import 'package:dart_dev/src/tasks/local/config.dart';
@@ -41,6 +42,7 @@ class Config {
   InitConfig init = new InitConfig();
   TaskRunnerConfig taskRunner = new TaskRunnerConfig();
   TestConfig test = new TestConfig();
+  SassConfig sass = new SassConfig();
 
   Map<String, dynamic> toJson() => {
         'analyze': analyze,
@@ -53,6 +55,7 @@ class Config {
         'init': init,
         'taskRunner': taskRunner,
         'test': test,
+        'sass': sass,
       };
 }
 

lib/src/tasks/sass/api.dart

@@ -0,0 +1,111 @@
+// Copyright 2015 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+library dart_dev.src.tasks.format.api;
+
+import 'dart:async';
+
+import 'package:args/args.dart';
+import 'package:dart_dev/src/tasks/sass/cli.dart';
+import 'package:meta/meta.dart';
+import 'package:w_common/sass.dart' as wc;
+import 'package:dart_dev/util.dart' show TaskProcess;
+
+import 'package:dart_dev/src/tasks/task.dart';
+
+const String intentionalInternalProxyArg = '--iprx=true';
+
+SassTask sass({
+  @required String sourceDir,
+  @required String outputDir,
+  @required List<String> watchDirs,
+  bool release: false,
+  bool preReleaseCheck: false,
+  ArgResults parsedArgs,
+}) {
+  var executable = 'pub';
+  var args = <String>[
+    'run',
+    'dart_dev:compile_sass_proxy',
+    intentionalInternalProxyArg,
+  ];
+
+  final reservedArgs = <String, dynamic>{
+    '--${wc.sourceDirArg}': sourceDir,
+    '--${wc.outputDirArg}': outputDir,
+    '--${wc.watchDirsArg}': watchDirs,
+    '--${wc.outputStyleArg}': release ? 'compressed' : 'expanded',
+    // Make sure the file name matches the un-minified checked in source when the release option is set.
+    '--${wc.compressedOutputStyleFileExtensionArg}': release
+        ? parsedArgs[wc.expandedOutputStyleFileExtensionArg]
+        : parsedArgs[wc.compressedOutputStyleFileExtensionArg],
+  };
+
+  reservedArgs.forEach((argName, argValue) {
+    if (argValue != null) {
+      if (argName == '--${wc.outputDirArg}' &&
+          argValue == reservedArgs['--${wc.sourceDirArg}']) return;
+      if (argName == '--${wc.compressedOutputStyleFileExtensionArg}' &&
+          argValue == '--${wc.compressedOutputStyleFileExtensionDefaultValue}')
+        return;
+      if (argName == '--${wc.expandedOutputStyleFileExtensionArg}' &&
+          argValue == '--${wc.expandedOutputStyleFileExtensionDefaultValue}')
+        return;
+
+      args.add('$argName=$argValue');
+    }
+  });
+
+  for (var arg in parsedArgs.arguments
+      .where((_arg) => !reservedArgs.keys.any((key) => _arg.startsWith(key)))) {
+    if (arg == '--$releaseArgName' || arg == '-$releaseArgAbbr') continue;
+
+    args.add(arg);
+  }
+
+  for (var arg in parsedArgs.rest
+      .where((_arg) => !reservedArgs.keys.any((key) => _arg.startsWith(key)))) {
+    args.add(arg);
+  }
+
+  if (preReleaseCheck) {
+    args
+      ..removeWhere((arg) => arg.contains('--${wc.outputStyleArg}'))
+      ..add('--${wc.outputStyleArg}=expanded')
+      ..add('--check');
+  }
+
+  final process = new TaskProcess(executable, args);
+  final task = new SassTask(
+      '$executable ${args.join(' ')}', process.done.then((_) => null));
+  process.stdout.listen(task._sassOutput.add);
+  process.stderr.listen(task._sassOutput.addError);
+  process.exitCode.then((code) {
+    task.successful = code <= 0;
+  });
+
+  return task;
+}
+
+class SassTask extends Task {
+  @override
+  final Future<Null> done;
+  final String sassCommand;
+
+  StreamController<String> _sassOutput = new StreamController();
+
+  SassTask(String this.sassCommand, this.done);
+
+  Stream<String> get sassOutput => _sassOutput.stream;
+}

lib/src/tasks/sass/cli.dart

@@ -0,0 +1,103 @@
+// Copyright 2019 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+library dart_dev.src.tasks.sass.cli;
+
+import 'dart:async';
+
+import 'package:args/args.dart';
+import 'package:dart_dev/util.dart' show reporter;
+import 'package:w_common/sass.dart' as wc;
+
+import 'package:dart_dev/src/tasks/sass/api.dart';
+import 'package:dart_dev/src/tasks/cli.dart';
+import 'package:dart_dev/src/tasks/config.dart';
+
+const String releaseArgName = 'release';
+const String releaseArgAbbr = 'r';
+
+class SassCli extends TaskCli {
+  @override
+  final ArgParser argParser = wc.sassCliArgs
+    ..addSeparator('-' * 80)
+    ..addFlag(releaseArgName,
+        negatable: false,
+        abbr: releaseArgAbbr,
+        help:
+            'Whether to compile minified CSS for bundling with a pub package. \n'
+            'Typically only set during a CI run. \n'
+            'A check of the unminified output will be performed first.');
+
+  @override
+  final String command = 'sass';
+
+  @override
+  String get usage =>
+      '${super.usage} [.scss file(s)...] \n\n${argParser.usage}';
+
+  @override
+  Future<CliResult> run(ArgResults parsedArgs, {bool color: true}) async {
+    bool help = TaskCli.valueOf('help', parsedArgs, false);
+    if (help) {
+      print(usage);
+      return new CliResult.success();
+    }
+
+    String sourceDir =
+        TaskCli.valueOf(wc.sourceDirArg, parsedArgs, config.sass.sourceDir);
+    String outputDir = TaskCli.valueOf(
+        wc.outputDirArg, parsedArgs, config.sass.outputDir ?? sourceDir);
+    List<String> watchDirs =
+        TaskCli.valueOf(wc.watchDirsArg, parsedArgs, config.sass.watchDirs);
+    bool release =
+        TaskCli.valueOf(releaseArgName, parsedArgs, config.sass.release);
+
+    if (release && !parsedArgs['help']) {
+      // If running in "release mode", we want to first run a check on the committed (unminified) CSS output
+      // and then immediately run it again to generate a minified copy using the same .scss sources to be
+      // tar'd up for pub package assets in CI
+      SassTask checkTask = sass(
+        sourceDir: sourceDir,
+        outputDir: outputDir,
+        watchDirs: watchDirs,
+        release: false,
+        preReleaseCheck: true,
+        parsedArgs: parsedArgs,
+      );
+      if (checkTask.sassCommand != null) {
+        reporter.logGroup(checkTask.sassCommand,
+            outputStream: checkTask.sassOutput);
+      }
+      await checkTask.done;
+
+      if (!checkTask.successful) return new CliResult.fail();
+    }
+
+    SassTask task = sass(
+      sourceDir: sourceDir,
+      outputDir: outputDir,
+      watchDirs: watchDirs,
+      release: release,
+      parsedArgs: parsedArgs,
+    );
+    if (task.sassCommand != null) {
+      reporter.logGroup(task.sassCommand, outputStream: task.sassOutput);
+    }
+    await task.done;
+
+    if (!task.successful) return new CliResult.fail('Sass compilation failed.');
+
+    return new CliResult.success('Sass compilation completed successfully');
+  }
+}

lib/src/tasks/sass/config.dart

@@ -0,0 +1,33 @@
+// Copyright 2019 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+library dart_dev.src.tasks.sass.config;
+
+import 'package:w_common/sass.dart' as wc;
+
+import 'package:dart_dev/src/tasks/config.dart';
+
+class SassConfig extends TaskConfig {
+  String sourceDir = wc.sourceDirDefaultValue;
+  String outputDir;
+  List<String> watchDirs;
+  bool release = false;
+
+  Map<String, dynamic> toJson() => {
+        'sourceDir': sourceDir,
+        'outputDir': outputDir,
+        'watchDirs': watchDirs,
+        'minify': false,
+      };
+}

pubspec.yaml

@@ -15,14 +15,17 @@ dependencies:
   args: '>=0.13.7 <2.0.0'
   dart2_constant: ^1.0.1
   path: ^1.3.6
+  meta: ^1.0.0
   resource: '>=1.0.0 <3.0.0'
   uuid: '>=0.5.0 <2.0.0'
+  w_common: ^1.19.0
   yaml: ^2.1.0
 
 dev_dependencies:
   coverage: '>=0.9.3 <0.13.0'
   dart_style: ^1.0.7
   dependency_validator: ^1.1.0
+  glob: ^1.1.7
   test: '>=0.12.24 <2.0.0'
 
 executables:
@@ -34,3 +37,4 @@ environment:
 transformers:
   - test/pub_serve:
       $include: test/**_test{.*,}.dart
+