For 'dartdev format' and 'dartdev format --help', return the output from dartfmt --help, instead of the default output from FormatCommand.printUsage(). This is follow up on https://dart-review.googlesource.com/c/sdk/+/133042

Change-Id: I497e983a2302fbb010256a4961b6121294a9de82
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/134106
Commit-Queue: Jaime Wren <jwren@google.com>
Reviewed-by: Devon Carew <devoncarew@google.com>

pkg/dartdev/lib/dartdev.dart

@@ -31,6 +31,10 @@ class DartdevRunner<int> extends CommandRunner {
     final Ansi ansi = Ansi(Ansi.terminalSupportsAnsi);
     log = isVerbose ? Logger.verbose(ansi: ansi) : Logger.standard(ansi: ansi);
 
+    // TODO(jwren) override this super call so that the arguments on each
+    //  command aren't enforced. Example:
+    //  dart .../dartdev.dart format -w /path/to/file.dart
+    // fails becuase '-w' isn't known by the FormatCommand class.
     return await super.runCommand(results);
   }
 }

pkg/dartdev/lib/src/commands/format.dart

@@ -9,19 +9,31 @@ import '../sdk.dart';
 
 class FormatCommand extends DartdevCommand {
   FormatCommand({bool verbose = false})
-      : super('format', 'Format one or more Dart files.') {
-    // TODO(jwren) add all options and flags
-  }
+      : super('format', 'Format one or more Dart files.');
 
   @override
   FutureOr<int> run() async {
-    // TODO(jwren) implement verbose in dart_style
-    // dartfmt doesn't have '-v' or '--verbose', so remove from the argument list
-    var args = List.from(argResults.arguments)
+    // TODO(jwren) The verbose flag was added to dartfmt in version 1.3.4 with
+    // https://github.com/dart-lang/dart_style/pull/887, this version is rolled
+    // into the dart sdk build, we can remove the removal of '-v' and
+    // '--verbose':
+    List<String> args = List.from(argResults.arguments)
       ..remove('-v')
       ..remove('--verbose');
+
+    if (args.isEmpty) {
+      args.add('--help');
+    }
+
     var process = await startProcess(sdk.dartfmt, args);
     routeToStdout(process);
     return process.exitCode;
   }
+
+  @override
+  void printUsage() {
+    var processResult = runSync(sdk.dartfmt, ['--help']);
+    String result = processResult.stdout;
+    print(result);
+  }
 }

pkg/dartdev/lib/src/core.dart

@@ -33,6 +33,15 @@ Future<Process> startProcess(
   return Process.start(executable, arguments, workingDirectory: cwd);
 }
 
+ProcessResult runSync(
+  String executable,
+  List<String> arguments, {
+  String cwd,
+}) {
+  log.trace('$executable ${arguments.join(' ')}');
+  return Process.runSync(executable, arguments, workingDirectory: cwd);
+}
+
 void routeToStdout(
   Process process, {
   bool logToTrace = false,

pkg/dartdev/test/commands/flag_test.dart

@@ -22,6 +22,7 @@ void help() {
     var result = p.runSync('--help');
 
     expect(result.exitCode, 0);
+    expect(result.stderr, isEmpty);
     expect(result.stdout, contains(DartdevRunner.dartdevDescription));
     expect(result.stdout, contains('Usage: dartdev <command> [arguments]'));
     expect(result.stdout, contains('Global options:'));

pkg/dartdev/test/commands/format_test.dart

@@ -15,13 +15,25 @@ void format() {
 
   tearDown(() => p?.dispose());
 
+  test('implicit --help', () {
+    p = project();
+    var result = p.runSync('format');
+    expect(result.exitCode, 0);
+    expect(result.stderr, isEmpty);
+    expect(result.stdout, contains('Idiomatically formats Dart source code.'));
+    expect(result.stdout,
+        contains('dartfmt [options...] [files or directories...]'));
+    expect(result.stdout, contains('dartfmt -w .'));
+  });
+
   test('--help', () {
     p = project();
     var result = p.runSync('format', ['--help']);
     expect(result.exitCode, 0);
-    expect(result.stdout, contains('Format one or more Dart files.'));
-    expect(result.stdout, contains('Usage: dartdev format [arguments]'));
-    expect(
-        result.stdout, contains('Run "dartdev help" to see global options.'));
+    expect(result.stderr, isEmpty);
+    expect(result.stdout, contains('Idiomatically formats Dart source code.'));
+    expect(result.stdout,
+        contains('dartfmt [options...] [files or directories...]'));
+    expect(result.stdout, contains('dartfmt -w .'));
   });
 }