From 22b910c3376df191dc46a65ecbcfa4460142bcd1 Mon Sep 17 00:00:00 2001
From: Janice Collins <jcollins@google.com>
Date: Thu, 3 Jan 2019 12:04:33 -0800
Subject: [PATCH] Fix help and add test for it

---
 bin/dartdoc.dart       | 1 +
 test/dartdoc_test.dart | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/bin/dartdoc.dart b/bin/dartdoc.dart
index 3626038747..840eef6865 100644
--- a/bin/dartdoc.dart
+++ b/bin/dartdoc.dart
@@ -120,6 +120,7 @@ Future<void> main(List<String> arguments) async {
 /// Print help if we are passed the help option.
 void _printHelp(ArgParser parser) {
   print('Generate HTML documentation for Dart libraries.\n');
+  print(parser.usage);
 }
 
 /// Print usage information on invalid command lines.
diff --git a/test/dartdoc_test.dart b/test/dartdoc_test.dart
index af0b7d9851..db2be45eba 100644
--- a/test/dartdoc_test.dart
+++ b/test/dartdoc_test.dart
@@ -152,6 +152,13 @@ void main() {
             throwsA(const TypeMatcher<ProcessException>()));
       });
 
+      test('help prints command line args', () async {
+        List<String> outputLines = [];
+        await subprocessLauncher.runStreamed(Platform.resolvedExecutable, [dartdocPath, '--help'], perLine: outputLines.add);
+        expect(outputLines, contains('Generate HTML documentation for Dart libraries.'));
+        expect(outputLines.join('\n'), contains(new RegExp('^-h, --help[ ]+Show command help.', multiLine: true))) ;
+      });
+
       test('Validate missing FLUTTER_ROOT exception is clean', () async {
         StringBuffer output = new StringBuffer();
         var args = <String>[dartdocPath];