Improve detection of when to use colors.

dart/lib/compiler/implementation/dart2js.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #library('dart2js');
 
 #import('dart:io');
 #import('dart:uri');
 #import('dart:utf');
 
@@ skipping 58 matching lines @@
   bool throwOnError = false;
   bool showWarnings = true;
   bool verbose = false;
   Uri libraryRoot = cwd;
   Uri out = cwd.resolve('out.js');
   Uri sourceMapOut = cwd.resolve('out.js.map');
   Uri packageRoot = null;
   List<String> options = new List<String>();
   bool explicitOut = false;
   bool wantHelp = false;
-  bool enableColors = true;
+  bool enableColors = false;
 
   passThrough(String argument) => options.add(argument);
 
   setLibraryRoot(String argument) {
     libraryRoot = cwd.resolve(extractPath(argument));
   }
 
   setPackageRoot(String argument) {
     packageRoot = cwd.resolve(extractPath(argument));
   }
@@ skipping 28 matching lines @@
   List<OptionHandler> handlers = <OptionHandler>[
     new OptionHandler('-[chv?]+', handleShortOptions),
     new OptionHandler('--throw-on-error', (_) => throwOnError = true),
     new OptionHandler('--suppress-warnings', (_) => showWarnings = false),
     new OptionHandler('--output-type=dart|--output-type=js', passThrough),
     new OptionHandler('--verbose', (_) => verbose = true),
     new OptionHandler('--library-root=.+', setLibraryRoot),
     new OptionHandler('--out=.+|-o.+', setOutput),
     new OptionHandler('--allow-mock-compilation', passThrough),
     new OptionHandler('--minify', passThrough),
+    // TODO(ahe): Remove the --no-colors option.
     new OptionHandler('--no-colors', (_) => enableColors = false),
+    new OptionHandler('--colors', (_) => enableColors = true),
     new OptionHandler('--enable[_-]checked[_-]mode|--checked',
                       (_) => passThrough('--enable-checked-mode')),
     new OptionHandler(@'--help|/\?|/h', (_) => wantHelp = true),
     new OptionHandler(@'--package-root=.+|-p.+', setPackageRoot),
     // The following two options must come last.
     new OptionHandler('-.*', (String argument) {
       helpAndFail('Error: Unknown option "$argument".');
     }),
     new OptionHandler('.*', (String argument) {
       arguments.add(nativeToUriPath(argument));
@@ skipping 26 matching lines @@
       throw 'Error: Cannot read "${relativize(cwd, uri)}" (${ex.osError}).';
     }
     dartBytesRead += source.length;
     sourceFiles[uri.toString()] =
       new SourceFile(relativize(cwd, uri), source);
     return new Future.immediate(source);
   }
 
   void info(var message, [api.Diagnostic kind = api.Diagnostic.VERBOSE_INFO]) {
     if (!verbose && kind === api.Diagnostic.VERBOSE_INFO) return;
-    print('${colors.green("info:")} $message');
+    if (enableColors) {
+      print('${colors.green("info:")} $message');
+    } else {
+      print('info: $message');
+    }
   }
 
   bool isAborting = false;
 
   final int FATAL = api.Diagnostic.CRASH.ordinal | api.Diagnostic.ERROR.ordinal;
   final int INFO =
       api.Diagnostic.INFO.ordinal | api.Diagnostic.VERBOSE_INFO.ordinal;
 
   void handler(Uri uri, int begin, int end, String message,
                api.Diagnostic kind) {
@@ skipping 98 matching lines @@
 }
 
 void compilerMain(Options options) {
   var root = uriPathToNative("/$LIBRARY_ROOT");
   List<String> argv = ['--library-root=${options.script}$root'];
   argv.addAll(options.arguments);
   compile(argv);
 }
 
 void help() {
-  // This message should be no longer than 22 lines. The default
+  // This message should be no longer than 20 lines. The default
   // terminal size normally 80x24. Two lines are used for the prompts
-  // before and after running the compiler.
+  // before and after running the compiler. Another two lines may be
+  // used to print an error message.
   print('''
 Usage: dart2js [options] dartfile
 
 Compiles Dart to JavaScript.
 
 Common options:
   -o<file> Generate the output into <file>.
   -c       Insert runtime type checks and enable assertions (checked mode).
   -h       Display this message (add -v for information about all options).''');
 }
@@ skipping 19 matching lines @@
 
   -p<path>, --package-root=<path>
     Where to find packages, that is, "package:..." imports.
 
   --minify
     Generate minified output.
 
   --suppress-warnings
     Do not display any warnings.
 
-  --no-colors
-    Do not add colors to diagnostic messages.
+  --colors
+    Add colors to diagnostic messages.
 
 The following options are only used for compiler development and may
 be removed in a future version:
 
   --output-type=dart
     Output Dart code instead of JavaScript.
 
   --throw-on-error
     Throw an exception if a compile-time error is detected.
 
@@ skipping 29 matching lines @@
     } catch (ignored) {
       print('Internal error: error while printing exception');
     }
     try {
       print(trace);
     } finally {
       exit(253); // 253 is recognized as a crash by our test scripts.
     }
   }
 }