add verbose option to show hidden args

R=vsm@google.com

Review-Url: https://codereview.chromium.org/2569783003 .

pkg/dev_compiler/lib/src/analyzer/context.dart

@@ -74,14 +74,14 @@ class AnalyzerOptions {
         declaredVariables: declaredVariables);
   }
 
-  static void addArguments(ArgParser parser) {
+  static void addArguments(ArgParser parser, {bool hide: true}) {
     parser
       ..addOption('summary',
           abbr: 's', help: 'summary file(s) to include', allowMultiple: true)
       ..addOption('dart-sdk',
-          help: 'Dart SDK Path', defaultsTo: null, hide: true)
+          help: 'Dart SDK Path', defaultsTo: null, hide: hide)
       ..addOption('dart-sdk-summary',
-          help: 'Dart SDK Summary Path', defaultsTo: null, hide: true)
+          help: 'Dart SDK Summary Path', defaultsTo: null, hide: hide)
       ..addOption('package-root',
           abbr: 'p', help: 'Package root to resolve "package:" imports')
       ..addOption('url-mapping',

pkg/dev_compiler/lib/src/compiler/command.dart

@@ -14,22 +14,7 @@ import '../analyzer/context.dart' show AnalyzerOptions, parseDeclaredVariables;
 import 'compiler.dart' show BuildUnit, CompilerOptions, ModuleCompiler;
 import 'module_builder.dart';
 
-final ArgParser _argParser = () {
-  var argParser = new ArgParser(allowTrailingOptions: true)
-    ..addFlag('help', abbr: 'h', help: 'Display this message.')
-    ..addOption('out',
-        abbr: 'o', allowMultiple: true, help: 'Output file (required).')
-    ..addOption('module-root',
-        help: 'Root module directory.\n'
-            'Generated module paths are relative to this root.')
-    ..addOption('library-root',
-        help: 'Root of source files.\n'
-            'Generated library names are relative to this root.');
-  addModuleFormatOptions(argParser, allowMultiple: true);
-  AnalyzerOptions.addArguments(argParser);
-  CompilerOptions.addArguments(argParser);
-  return argParser;
-}();
+bool _verbose = false;
 
 /// Runs a single compile for dartdevc.
 ///
@@ -41,7 +26,8 @@ int compile(List<String> args, {void printFn(Object obj)}) {
   ArgResults argResults;
   var declaredVars = <String, String>{};
   try {
-    argResults = _argParser.parse(parseDeclaredVariables(args, declaredVars));
+    argResults = _argParser().parse(parseDeclaredVariables(args, declaredVars));
+    _verbose = argResults['verbose'];
   } on FormatException catch (error) {
     printFn('$error\n\n$_usageMessage');
     return 64;
@@ -80,6 +66,28 @@ $stackTrace
   }
 }
 
+ArgParser _argParser({bool hide: true}) {
+  var argParser = new ArgParser(allowTrailingOptions: true)
+    ..addFlag('help',
+        abbr: 'h',
+        help: 'Display this message.\n'
+            'Add --verbose to show hidden options.',
+        negatable: false)
+    ..addFlag('verbose', abbr: 'v', help: 'Verbose output.')
+    ..addOption('out',
+        abbr: 'o', allowMultiple: true, help: 'Output file (required).')
+    ..addOption('module-root',
+        help: 'Root module directory.\n'
+            'Generated module paths are relative to this root.')
+    ..addOption('library-root',
+        help: 'Root of source files.\n'
+            'Generated library names are relative to this root.');
+  addModuleFormatOptions(argParser, allowMultiple: true, hide: hide);
+  AnalyzerOptions.addArguments(argParser, hide: hide);
+  CompilerOptions.addArguments(argParser, hide: hide);
+  return argParser;
+}
+
 bool _changed(List<int> list1, List<int> list2) {
   var length = list1.length;
   if (length != list2.length) return true;
@@ -198,9 +206,9 @@ String _moduleForLibrary(
   return null; // unreachable
 }
 
-final _usageMessage =
+String get _usageMessage =>
     'Dart Development Compiler compiles Dart into a JavaScript module.'
-    '\n\n${_argParser.usage}';
+        '\n\n${_argParser(hide: !_verbose).usage}';
 
 void _usageException(String message) {
   throw new UsageException(message, _usageMessage);

pkg/dev_compiler/lib/src/compiler/compiler.dart

@@ -305,19 +305,19 @@ class CompilerOptions {
         bazelMapping = _parseBazelMappings(args['bazel-mapping']),
         summaryOutPath = args['summary-out'];
 
-  static void addArguments(ArgParser parser) {
+  static void addArguments(ArgParser parser, {bool hide: true}) {
     parser
       ..addFlag('summarize', help: 'emit an API summary file', defaultsTo: true)
       ..addOption('summary-extension',
           help: 'file extension for Dart summary files',
           defaultsTo: 'sum',
-          hide: true)
+          hide: hide)
       ..addFlag('source-map', help: 'emit source mapping', defaultsTo: true)
       ..addFlag('source-map-comment',
           help: 'adds a sourceMappingURL comment to the end of the JS,\n'
               'disable if using X-SourceMap header',
           defaultsTo: true,
-          hide: true)
+          hide: hide)
       ..addFlag('inline-source-map',
           help: 'emit source mapping inline', defaultsTo: false)
       ..addFlag('emit-metadata',
@@ -327,39 +327,39 @@ class CompilerOptions {
           help: 'emit Closure Compiler-friendly code (experimental)',
           defaultsTo: false)
       ..addFlag('destructure-named-params',
-          help: 'Destructure named parameters', defaultsTo: false, hide: true)
+          help: 'Destructure named parameters', defaultsTo: false, hide: hide)
       ..addFlag('unsafe-force-compile',
           help: 'Compile code even if it has errors. ಠ_ಠ\n'
               'This has undefined behavior!',
           defaultsTo: false,
-          hide: true)
+          hide: hide)
       ..addFlag('repl-compile',
-          help: 'Compile code more permissively when in REPL mode allowing '
-              'access to private members across library boundaries.',
+          help: 'Compile code more permissively when in REPL mode\n'
+              'allowing access to private members across library boundaries.',
           defaultsTo: false,
-          hide: true)
+          hide: hide)
       ..addFlag('hoist-instance-creation',
           help: 'Hoist the class type from generic instance creations',
           defaultsTo: true,
-          hide: true)
+          hide: hide)
       ..addFlag('hoist-signature-types',
           help: 'Hoist types from class signatures',
           defaultsTo: false,
-          hide: true)
+          hide: hide)
       ..addFlag('name-type-tests',
-          help: 'Name types used in type tests', defaultsTo: true, hide: true)
+          help: 'Name types used in type tests', defaultsTo: true, hide: hide)
       ..addFlag('hoist-type-tests',
-          help: 'Hoist types used in type tests', defaultsTo: true, hide: true)
-      ..addFlag('unsafe-angular2-whitelist', defaultsTo: false, hide: true)
+          help: 'Hoist types used in type tests', defaultsTo: true, hide: hide)
+      ..addFlag('unsafe-angular2-whitelist', defaultsTo: false, hide: hide)
       ..addOption('bazel-mapping',
           help:
               '--bazel-mapping=genfiles/to/library.dart,to/library.dart uses \n'
               'to/library.dart as the path for library.dart in source maps.',
           allowMultiple: true,
           splitCommas: false,
-          hide: true)
+          hide: hide)
       ..addOption('summary-out',
-          help: 'location to write the summary file', hide: true);
+          help: 'location to write the summary file', hide: hide);
   }
 
   static Map<String, String> _parseBazelMappings(Iterable argument) {

pkg/dev_compiler/lib/src/compiler/module_builder.dart

@@ -45,7 +45,8 @@ List<ModuleFormat> parseModuleFormatOption(ArgResults argResults) {
 /// Adds an option to the [argParser] for choosing the module format, optionally
 /// [allowMultiple] formats to be specified, with each emitted into a separate
 /// file.
-void addModuleFormatOptions(ArgParser argParser, {bool allowMultiple: false}) {
+void addModuleFormatOptions(ArgParser argParser,
+    {bool allowMultiple: false, bool hide: true}) {
   argParser
     ..addOption('modules',
         help: 'module pattern to emit',
@@ -68,7 +69,7 @@ void addModuleFormatOptions(ArgParser argParser, {bool allowMultiple: false}) {
         help: 'emit modules that can be concatenated into one file.\n'
             'Only compatible with legacy and amd module formats.',
         defaultsTo: false,
-        hide: true);
+        hide: hide);
 }
 
 /// Transforms an ES6 [module] into a given module [format].