pkg/compiler/lib/src/dart2js.dart - sdk.git - Git at Google

 // Copyright (c) 2013, 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.cmdline;

 import 'dart:async'
     show Future, EventSink;
 import 'dart:convert' show UTF8, LineSplitter;
 import 'dart:io'
     show exit, File, FileMode, Platform, RandomAccessFile, FileSystemException,
          stdin, stderr;

 import '../compiler.dart' as api;
 import 'source_file.dart';
 import 'source_file_provider.dart';
 import 'filenames.dart';
 import 'util/uri_extras.dart';
 import 'util/util.dart' show stackTraceFilePrefix;
 import 'util/command_line.dart';
 import 'package:_internal/libraries.dart';

 const String LIBRARY_ROOT = '../../../../../sdk';
 const String OUTPUT_LANGUAGE_DART = 'Dart';

 /**
  * A string to identify the revision or build.
  *
  * This ID is displayed if the compiler crashes and in verbose mode, and is
  * an aid in reproducing bug reports.
  *
  * The actual string is rewritten by a wrapper script when included in the sdk.
  */
 String BUILD_ID = null;

 /**
  * The data passed to the [HandleOption] callback is either a single
  * string argument, or the arguments iterator for multiple arguments
  * handlers.
  */
 typedef void HandleOption(data);

 class OptionHandler {
   final String pattern;
   final HandleOption handle;
   final bool multipleArguments;

   OptionHandler(this.pattern, this.handle, {this.multipleArguments: false});
 }

 /**
  * Extract the parameter of an option.
  *
  * For example, in ['--out=fisk.js'] and ['-ohest.js'], the parameters
  * are ['fisk.js'] and ['hest.js'], respectively.
  */
 String extractParameter(String argument, {bool isOptionalArgument: false}) {
   // m[0] is the entire match (which will be equal to argument). m[1]
   // is something like "-o" or "--out=", and m[2] is the parameter.
   Match m = new RegExp('^(-[a-z]|--.+=)(.*)').firstMatch(argument);
   if (m == null) {
     if (isOptionalArgument) return null;
     helpAndFail('Unknown option "$argument".');
   }
   return m[2];
 }

 String extractPath(String argument) {
   String path = nativeToUriPath(extractParameter(argument));
   return path.endsWith("/") ? path : "$path/";
 }

 void parseCommandLine(List<OptionHandler> handlers, List<String> argv) {
   // TODO(ahe): Use ../../args/args.dart for parsing options instead.
   var patterns = <String>[];
   for (OptionHandler handler in handlers) {
     patterns.add(handler.pattern);
   }
   var pattern = new RegExp('^(${patterns.join(")\$|^(")})\$');

   Iterator<String> arguments = argv.iterator;
   OUTER: while (arguments.moveNext()) {
     String argument = arguments.current;
     Match match = pattern.firstMatch(argument);
     assert(match.groupCount == handlers.length);
     for (int i = 0; i < handlers.length; i++) {
       if (match[i + 1] != null) {
         OptionHandler handler = handlers[i];
         if (handler.multipleArguments) {
           handler.handle(arguments);
         } else {
           handler.handle(argument);
         }
         continue OUTER;
       }
     }
     throw 'Internal error: "$argument" did not match';
   }
 }

 FormattingDiagnosticHandler diagnosticHandler;

 Future compile(List<String> argv) {
   stackTraceFilePrefix = '$currentDirectory';
   Uri libraryRoot = currentDirectory;
   Uri out = currentDirectory.resolve('out.js');
   Uri sourceMapOut = currentDirectory.resolve('out.js.map');
   Uri packageRoot = null;
   List<String> options = new List<String>();
   bool explicitOut = false;
   bool wantHelp = false;
   bool wantVersion = false;
   String outputLanguage = 'JavaScript';
   bool stripArgumentSet = false;
   bool analyzeOnly = false;
   bool analyzeAll = false;
   bool enableAsyncAwait = false;
   bool trustTypeAnnotations = false;
   bool trustPrimitives = false;
   bool checkedMode = false;
   // List of provided options that imply that output is expected.
   List<String> optionsImplyCompilation = <String>[];
   bool hasDisallowUnsafeEval = false;
   // TODO(johnniwinther): Measure time for reading files.
   SourceFileProvider inputProvider = new CompilerSourceFileProvider();
   diagnosticHandler = new FormattingDiagnosticHandler(inputProvider);
   Map<String, dynamic> environment = new Map<String, dynamic>();

   passThrough(String argument) => options.add(argument);

   if (BUILD_ID != null) {
     passThrough("--build-id=$BUILD_ID");
   }

   setLibraryRoot(String argument) {
     libraryRoot = currentDirectory.resolve(extractPath(argument));
   }

   setPackageRoot(String argument) {
     packageRoot = currentDirectory.resolve(extractPath(argument));
   }

   setOutput(Iterator<String> arguments) {
     optionsImplyCompilation.add(arguments.current);
     String path;
     if (arguments.current == '-o') {
       if (!arguments.moveNext()) {
         helpAndFail('Error: Missing file after -o option.');
       }
       path = arguments.current;
     } else {
       path = extractParameter(arguments.current);
     }
     explicitOut = true;
     out = currentDirectory.resolve(nativeToUriPath(path));
     sourceMapOut = Uri.parse('$out.map');
   }

   setOutputType(String argument) {
     optionsImplyCompilation.add(argument);
     if (argument == '--output-type=dart' ||
         argument == '--output-type=dart-multi') {
       outputLanguage = OUTPUT_LANGUAGE_DART;
       if (!explicitOut) {
         out = currentDirectory.resolve('out.dart');
         sourceMapOut = currentDirectory.resolve('out.dart.map');
       }
     }
     passThrough(argument);
   }

   String getDepsOutput(Map<String, SourceFile> sourceFiles) {
     var filenames = new List.from(sourceFiles.keys);
     filenames.sort();
     return filenames.join("\n");
   }

   setStrip(String argument) {
     optionsImplyCompilation.add(argument);
     stripArgumentSet = true;
     passThrough(argument);
   }

   setAnalyzeOnly(String argument) {
     analyzeOnly = true;
     passThrough(argument);
   }

   setAnalyzeAll(String argument) {
     analyzeAll = true;
     passThrough(argument);
   }

   setEnableAsync(String argument) {
     enableAsyncAwait = true;
     passThrough(argument);
   }

   setVerbose(_) {
     diagnosticHandler.verbose = true;
     passThrough('--verbose');
   }

   implyCompilation(String argument) {
     optionsImplyCompilation.add(argument);
     passThrough(argument);
   }

   setTrustTypeAnnotations(String argument) {
     trustTypeAnnotations = true;
     implyCompilation(argument);
   }

   setTrustPrimitives(String argument) {
     trustPrimitives = true;
     implyCompilation(argument);
   }

   setCheckedMode(String argument) {
     checkedMode = true;
     passThrough(argument);
   }

   addInEnvironment(String argument) {
     int eqIndex = argument.indexOf('=');
     String name = argument.substring(2, eqIndex);
     String value = argument.substring(eqIndex + 1);
     environment[name] = value;
   }

   setCategories(String argument) {
     List<String> categories = extractParameter(argument).split(',');
     Set<String> allowedCategories =
         LIBRARIES.values.map((x) => x.category).toSet();
     allowedCategories.remove('Shared');
     allowedCategories.remove('Internal');
     List<String> allowedCategoriesList =
         new List<String>.from(allowedCategories);
     allowedCategoriesList.sort();
     if (categories.contains('all')) {
       categories = allowedCategoriesList;
     } else {
       String allowedCategoriesString = allowedCategoriesList.join(', ');
       for (String category in categories) {
         if (!allowedCategories.contains(category)) {
           fail('Unsupported library category "$category", '
                'supported categories are: $allowedCategoriesString');
         }
       }
     }
     passThrough('--categories=${categories.join(",")}');
   }

   void handleThrowOnError(String argument) {
     diagnosticHandler.throwOnError = true;
     String parameter = extractParameter(argument, isOptionalArgument: true);
     if (parameter != null) {
       diagnosticHandler.throwOnErrorCount = int.parse(parameter);
     }
   }

   handleShortOptions(String argument) {
     var shortOptions = argument.substring(1).split("");
     for (var shortOption in shortOptions) {
       switch (shortOption) {
         case 'v':
           setVerbose(null);
           break;
         case 'h':
         case '?':
           wantHelp = true;
           break;
         case 'c':
           setCheckedMode('--enable-checked-mode');
           break;
         case 'm':
           implyCompilation('--minify');
           break;
         default:
           throw 'Internal error: "$shortOption" did not match';
       }
     }
   }

   List<String> arguments = <String>[];
   List<OptionHandler> handlers = <OptionHandler>[
     new OptionHandler('-[chvm?]+', handleShortOptions),
     new OptionHandler('--throw-on-error(?:=[0-9]+)?', handleThrowOnError),
     new OptionHandler('--suppress-warnings', (_) {
       diagnosticHandler.showWarnings = false;
       passThrough('--suppress-warnings');
     }),
     new OptionHandler('--suppress-hints',
                       (_) => diagnosticHandler.showHints = false),
     new OptionHandler(
         '--output-type=dart|--output-type=dart-multi|--output-type=js',
         setOutputType),
     new OptionHandler('--verbose', setVerbose),
     new OptionHandler('--version', (_) => wantVersion = true),
     new OptionHandler('--library-root=.+', setLibraryRoot),
     new OptionHandler('--out=.+|-o.*', setOutput, multipleArguments: true),
     new OptionHandler('--allow-mock-compilation', passThrough),
     new OptionHandler('--minify|-m', implyCompilation),
     new OptionHandler('--preserve-uris', passThrough),
     new OptionHandler('--force-strip=.*', setStrip),
     new OptionHandler('--disable-diagnostic-colors',
                       (_) => diagnosticHandler.enableColors = false),
     new OptionHandler('--enable-diagnostic-colors',
                       (_) => diagnosticHandler.enableColors = true),
     new OptionHandler('--enable[_-]checked[_-]mode|--checked',
                       (_) => setCheckedMode('--enable-checked-mode')),
     new OptionHandler('--enable-concrete-type-inference',
                       (_) => implyCompilation(
                           '--enable-concrete-type-inference')),
     new OptionHandler('--trust-type-annotations',
                       (_) => setTrustTypeAnnotations(
                           '--trust-type-annotations')),
     new OptionHandler('--trust-primitives',
                       (_) => setTrustPrimitives(
                           '--trust-primitives')),
     new OptionHandler(r'--help|/\?|/h', (_) => wantHelp = true),
     new OptionHandler('--package-root=.+|-p.+', setPackageRoot),
     new OptionHandler('--analyze-all', setAnalyzeAll),
     new OptionHandler('--analyze-only', setAnalyzeOnly),
     new OptionHandler('--analyze-signatures-only', setAnalyzeOnly),
     new OptionHandler('--disable-native-live-type-analysis', passThrough),
     new OptionHandler('--categories=.*', setCategories),
     new OptionHandler('--disable-type-inference', implyCompilation),
     new OptionHandler('--terse', passThrough),
     new OptionHandler('--dump-info', implyCompilation),
     new OptionHandler('--disallow-unsafe-eval',
                       (_) => hasDisallowUnsafeEval = true),
     new OptionHandler('--show-package-warnings', passThrough),
     new OptionHandler('--csp', passThrough),
     new OptionHandler('--enable-experimental-mirrors', passThrough),
     new OptionHandler('--enable-async', setEnableAsync),
     new OptionHandler('--enable-enum', passThrough),
     new OptionHandler('-D.+=.*', addInEnvironment),

     // The following two options must come last.
     new OptionHandler('-.*', (String argument) {
       helpAndFail("Unknown option '$argument'.");
     }),
     new OptionHandler('.*', (String argument) {
       arguments.add(nativeToUriPath(argument));
     })
   ];

   parseCommandLine(handlers, argv);
   if (wantHelp || wantVersion) {
     helpAndExit(wantHelp, wantVersion, diagnosticHandler.verbose);
   }

   if (hasDisallowUnsafeEval) {
     String precompiledName =
         relativize(currentDirectory,
                    RandomAccessFileOutputProvider.computePrecompiledUri(out),
                    Platform.isWindows);
     helpAndFail("Option '--disallow-unsafe-eval' has been removed."
                 " Instead, the compiler generates a file named"
                 " '$precompiledName'.");
   }

   if (outputLanguage != OUTPUT_LANGUAGE_DART && stripArgumentSet) {
     helpAndFail("Option '--force-strip' may only be used with "
                 "'--output-type=dart'.");
   }
   if (arguments.isEmpty) {
     helpAndFail('No Dart file specified.');
   }
   if (arguments.length > 1) {
     var extra = arguments.sublist(1);
     helpAndFail('Extra arguments: ${extra.join(" ")}');
   }

   if (checkedMode && trustTypeAnnotations) {
     helpAndFail("Option '--trust-type-annotations' may not be used in "
                 "checked mode.");
   }

   Uri uri = currentDirectory.resolve(arguments[0]);
   if (packageRoot == null) {
     packageRoot = uri.resolve('./packages/');
   }

   if ((analyzeOnly || analyzeAll) && !optionsImplyCompilation.isEmpty) {
     if (!analyzeOnly) {
       diagnosticHandler.info(
           "Option '--analyze-all' implies '--analyze-only'.",
           api.Diagnostic.INFO);
     }
     diagnosticHandler.info(
         "Options $optionsImplyCompilation indicate that output is expected, "
         "but compilation is turned off by the option '--analyze-only'.",
         api.Diagnostic.INFO);
   }
   if (analyzeAll) analyzeOnly = true;
   if (enableAsyncAwait && !analyzeOnly) {
     helpAndFail("Option '--enable-async' is currently only supported in "
                 "combination with the '--analyze-only' option.");
   }

   diagnosticHandler.info('Package root is $packageRoot');

   options.add('--out=$out');
   options.add('--source-map=$sourceMapOut');

   RandomAccessFileOutputProvider outputProvider =
       new RandomAccessFileOutputProvider(
           out, sourceMapOut, onInfo: diagnosticHandler.info, onFailure: fail);

   compilationDone(String code) {
     if (analyzeOnly) return;
     if (code == null) {
       fail('Compilation failed.');
     }
     writeString(Uri.parse('$out.deps'),
                 getDepsOutput(inputProvider.sourceFiles));
     diagnosticHandler.info(
          'Compiled ${inputProvider.dartCharactersRead} characters Dart '
          '-> ${outputProvider.totalCharactersWritten} characters '
          '$outputLanguage in '
          '${relativize(currentDirectory, out, Platform.isWindows)}');
     if (diagnosticHandler.verbose) {
       String input = uriPathToNative(arguments[0]);
       print('Dart file ($input) compiled to $outputLanguage.');
       print('Wrote the following files:');
       for (String filename in outputProvider.allOutputFiles) {
         print("  $filename");
       }
     } else if (!explicitOut) {
       String input = uriPathToNative(arguments[0]);
       String output = relativize(currentDirectory, out, Platform.isWindows);
       print('Dart file ($input) compiled to $outputLanguage: $output');
     }
   }

   return compileFunc(uri, libraryRoot, packageRoot,
                      inputProvider, diagnosticHandler,
                      options, outputProvider, environment)
             .then(compilationDone);
 }

 class AbortLeg {
   final message;
   AbortLeg(this.message);
   toString() => 'Aborted due to --throw-on-error: $message';
 }

 void writeString(Uri uri, String text) {
   if (uri.scheme != 'file') {
     fail('Unhandled scheme ${uri.scheme}.');
   }
   var file = new File(uri.toFilePath()).openSync(mode: FileMode.WRITE);
   file.writeStringSync(text);
   file.closeSync();
 }

 void fail(String message) {
   if (diagnosticHandler != null) {
     diagnosticHandler.diagnosticHandler(
         null, -1, -1, message, api.Diagnostic.ERROR);
   } else {
     print('Error: $message');
   }
   exitFunc(1);
 }

 Future compilerMain(List<String> arguments) {
   var root = uriPathToNative("/$LIBRARY_ROOT");
   arguments = <String>['--library-root=${Platform.script.toFilePath()}$root']
       ..addAll(arguments);
   return compile(arguments);
 }

 void help() {
   // 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. 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).
   -m        Generate minified output.
   -h        Display this message (add -v for information about all options).''');
 }

 void verboseHelp() {
   print(r'''
 Usage: dart2js [options] dartfile

 Compiles Dart to JavaScript.

 Supported options:
   -o <file>, --out=<file>
     Generate the output into <file>.

   -c, --enable-checked-mode, --checked
     Insert runtime type checks and enable assertions (checked mode).

   -m, --minify
     Generate minified output.

   -h, /h, /?, --help
     Display this message (add -v for information about all options).

   -v, --verbose
     Display verbose information.

   -D<name>=<value>
     Define an environment variable.

   --version
     Display version information.

   -p<path>, --package-root=<path>
     Where to find packages, that is, "package:..." imports.

   --analyze-all
     Analyze all code.  Without this option, the compiler only analyzes
     code that is reachable from [main].  This option implies --analyze-only.

   --analyze-only
     Analyze but do not generate code.

   --analyze-signatures-only
     Skip analysis of method bodies and field initializers. This option implies
     --analyze-only.

   --suppress-warnings
     Do not display any warnings.

   --suppress-hints
     Do not display any hints.

   --enable-diagnostic-colors
     Add colors to diagnostic messages.

   --terse
     Emit diagnostics without suggestions for how to get rid of the diagnosed
     problems.

   --show-package-warnings
     Show warnings and hints generated from packages.

   --preserve-uris
     Preserve the source URIs in the reflection data. Without this flag the
     `uri` getter for `LibraryMirror`s is mangled in minified mode.

   --csp
     Disables dynamic generation of code in the generated output. This is
     necessary to satisfy CSP restrictions (see http://www.w3.org/TR/CSP/).

 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.

   --library-root=<directory>
     Where to find the Dart platform libraries.

   --allow-mock-compilation
     Do not generate a call to main if either of the following
     libraries are used: dart:dom, dart:html dart:io.

   --enable-concrete-type-inference
     Enable experimental concrete type inference.

   --disable-native-live-type-analysis
     Disable the optimization that removes unused native types from dart:html
     and related libraries.

   --categories=<categories>
     A comma separated list of allowed library categories.  The default
     is "Client".  Possible categories can be seen by providing an
     unsupported category, for example, --categories=help.  To enable
     all categories, use --categories=all.

   --dump-info
     Generates an out.info.json file with information about the generated code.
     You can inspect the generated file with the viewer at:
     https://dart-lang.github.io/dump-info-visualizer/

 '''.trim());
 }

 void helpAndExit(bool wantHelp, bool wantVersion, bool verbose) {
   if (wantVersion) {
     var version = (BUILD_ID == null)
         ? '<non-SDK build>'
         : BUILD_ID;
     print('Dart-to-JavaScript compiler (dart2js) version: $version');
   }
   if (wantHelp) {
     if (verbose) {
       verboseHelp();
     } else {
       help();
     }
   }
   exitFunc(0);
 }

 void helpAndFail(String message) {
   help();
   print('');
   fail(message);
 }

 void main(List<String> arguments) {
   // Since the sdk/bin/dart2js script adds its own arguments in front of
   // user-supplied arguments we search for '--batch' at the end of the list.
   if (arguments.length > 0 && arguments.last == "--batch") {
     batchMain(arguments.sublist(0, arguments.length - 1));
     return;
   }
   internalMain(arguments);
 }

 var exitFunc = exit;
 var compileFunc = api.compile;

 Future internalMain(List<String> arguments) {
   onError(exception, trace) {
     try {
       print('The compiler crashed: $exception');
     } catch (ignored) {
       print('The compiler crashed: error while printing exception');
     }

     try {
       if (trace != null) {
         print(trace);
       }
     } finally {
       exitFunc(253); // 253 is recognized as a crash by our test scripts.
     }
   }

   try {
     return compilerMain(arguments).catchError(onError);
   } catch (exception, trace) {
     onError(exception, trace);
     return new Future.value();
   }
 }

 const _EXIT_SIGNAL = const Object();

 void batchMain(List<String> batchArguments) {
   int exitCode;
   exitFunc = (errorCode) {
     // Since we only throw another part of the compiler might intercept our
     // exception and try to exit with a different code.
     if (exitCode == 0) {
       exitCode = errorCode;
     }
     throw _EXIT_SIGNAL;
   };

   var stream = stdin.transform(UTF8.decoder).transform(new LineSplitter());
   var subscription;
   subscription = stream.listen((line) {
     new Future.sync(() {
       subscription.pause();
       exitCode = 0;
       if (line == null) exit(0);
       List<String> args = <String>[];
       args.addAll(batchArguments);
       args.addAll(splitLine(line, windows: Platform.isWindows));
       return internalMain(args);
     }).catchError((exception, trace) {
       if (!identical(exception, _EXIT_SIGNAL)) {
         exitCode = 253;
       }
     }).whenComplete(() {
       // The testing framework waits for a status line on stdout and
       // stderr before moving to the next test.
       if (exitCode == 0){
         print(">>> TEST OK");
       } else if (exitCode == 253) {
         print(">>> TEST CRASH");
       } else {
         print(">>> TEST FAIL");
       }
       stderr.writeln(">>> EOF STDERR");
       subscription.resume();
     });
   });
 }
	// Copyright (c) 2013, 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.cmdline;

	import 'dart:async'
	show Future, EventSink;
	import 'dart:convert' show UTF8, LineSplitter;
	import 'dart:io'
	show exit, File, FileMode, Platform, RandomAccessFile, FileSystemException,
	stdin, stderr;

	import '../compiler.dart' as api;
	import 'source_file.dart';
	import 'source_file_provider.dart';
	import 'filenames.dart';
	import 'util/uri_extras.dart';
	import 'util/util.dart' show stackTraceFilePrefix;
	import 'util/command_line.dart';
	import 'package:_internal/libraries.dart';

	const String LIBRARY_ROOT = '../../../../../sdk';
	const String OUTPUT_LANGUAGE_DART = 'Dart';

	/**
	* A string to identify the revision or build.
	*
	* This ID is displayed if the compiler crashes and in verbose mode, and is
	* an aid in reproducing bug reports.
	*
	* The actual string is rewritten by a wrapper script when included in the sdk.
	*/
	String BUILD_ID = null;

	/**
	* The data passed to the [HandleOption] callback is either a single
	* string argument, or the arguments iterator for multiple arguments
	* handlers.
	*/
	typedef void HandleOption(data);

	class OptionHandler {
	final String pattern;
	final HandleOption handle;
	final bool multipleArguments;

	OptionHandler(this.pattern, this.handle, {this.multipleArguments: false});
	}

	/**
	* Extract the parameter of an option.
	*
	* For example, in ['--out=fisk.js'] and ['-ohest.js'], the parameters
	* are ['fisk.js'] and ['hest.js'], respectively.
	*/
	String extractParameter(String argument, {bool isOptionalArgument: false}) {
	// m[0] is the entire match (which will be equal to argument). m[1]
	// is something like "-o" or "--out=", and m[2] is the parameter.
	Match m = new RegExp('^(-[a-z]\|--.+=)(.*)').firstMatch(argument);
	if (m == null) {
	if (isOptionalArgument) return null;
	helpAndFail('Unknown option "$argument".');
	}
	return m[2];
	}

	String extractPath(String argument) {
	String path = nativeToUriPath(extractParameter(argument));
	return path.endsWith("/") ? path : "$path/";
	}

	void parseCommandLine(List<OptionHandler> handlers, List<String> argv) {
	// TODO(ahe): Use ../../args/args.dart for parsing options instead.
	var patterns = <String>[];
	for (OptionHandler handler in handlers) {
	patterns.add(handler.pattern);
	}
	var pattern = new RegExp('^(${patterns.join(")\$\|^(")})\$');

	Iterator<String> arguments = argv.iterator;
	OUTER: while (arguments.moveNext()) {
	String argument = arguments.current;
	Match match = pattern.firstMatch(argument);
	assert(match.groupCount == handlers.length);
	for (int i = 0; i < handlers.length; i++) {
	if (match[i + 1] != null) {
	OptionHandler handler = handlers[i];
	if (handler.multipleArguments) {
	handler.handle(arguments);
	} else {
	handler.handle(argument);
	}
	continue OUTER;
	}
	}
	throw 'Internal error: "$argument" did not match';
	}
	}

	FormattingDiagnosticHandler diagnosticHandler;

	Future compile(List<String> argv) {
	stackTraceFilePrefix = '$currentDirectory';
	Uri libraryRoot = currentDirectory;
	Uri out = currentDirectory.resolve('out.js');
	Uri sourceMapOut = currentDirectory.resolve('out.js.map');
	Uri packageRoot = null;
	List<String> options = new List<String>();
	bool explicitOut = false;
	bool wantHelp = false;
	bool wantVersion = false;
	String outputLanguage = 'JavaScript';
	bool stripArgumentSet = false;
	bool analyzeOnly = false;
	bool analyzeAll = false;
	bool enableAsyncAwait = false;
	bool trustTypeAnnotations = false;
	bool trustPrimitives = false;
	bool checkedMode = false;
	// List of provided options that imply that output is expected.
	List<String> optionsImplyCompilation = <String>[];
	bool hasDisallowUnsafeEval = false;
	// TODO(johnniwinther): Measure time for reading files.
	SourceFileProvider inputProvider = new CompilerSourceFileProvider();
	diagnosticHandler = new FormattingDiagnosticHandler(inputProvider);
	Map<String, dynamic> environment = new Map<String, dynamic>();

	passThrough(String argument) => options.add(argument);

	if (BUILD_ID != null) {
	passThrough("--build-id=$BUILD_ID");
	}

	setLibraryRoot(String argument) {
	libraryRoot = currentDirectory.resolve(extractPath(argument));
	}

	setPackageRoot(String argument) {
	packageRoot = currentDirectory.resolve(extractPath(argument));
	}

	setOutput(Iterator<String> arguments) {
	optionsImplyCompilation.add(arguments.current);
	String path;
	if (arguments.current == '-o') {
	if (!arguments.moveNext()) {
	helpAndFail('Error: Missing file after -o option.');
	}
	path = arguments.current;
	} else {
	path = extractParameter(arguments.current);
	}
	explicitOut = true;
	out = currentDirectory.resolve(nativeToUriPath(path));
	sourceMapOut = Uri.parse('$out.map');
	}

	setOutputType(String argument) {
	optionsImplyCompilation.add(argument);
	if (argument == '--output-type=dart' \|\|
	argument == '--output-type=dart-multi') {
	outputLanguage = OUTPUT_LANGUAGE_DART;
	if (!explicitOut) {
	out = currentDirectory.resolve('out.dart');
	sourceMapOut = currentDirectory.resolve('out.dart.map');
	}
	}
	passThrough(argument);
	}

	String getDepsOutput(Map<String, SourceFile> sourceFiles) {
	var filenames = new List.from(sourceFiles.keys);
	filenames.sort();
	return filenames.join("\n");
	}

	setStrip(String argument) {
	optionsImplyCompilation.add(argument);
	stripArgumentSet = true;
	passThrough(argument);
	}

	setAnalyzeOnly(String argument) {
	analyzeOnly = true;
	passThrough(argument);
	}

	setAnalyzeAll(String argument) {
	analyzeAll = true;
	passThrough(argument);
	}

	setEnableAsync(String argument) {
	enableAsyncAwait = true;
	passThrough(argument);
	}

	setVerbose(_) {
	diagnosticHandler.verbose = true;
	passThrough('--verbose');
	}

	implyCompilation(String argument) {
	optionsImplyCompilation.add(argument);
	passThrough(argument);
	}

	setTrustTypeAnnotations(String argument) {
	trustTypeAnnotations = true;
	implyCompilation(argument);
	}

	setTrustPrimitives(String argument) {
	trustPrimitives = true;
	implyCompilation(argument);
	}

	setCheckedMode(String argument) {
	checkedMode = true;
	passThrough(argument);
	}

	addInEnvironment(String argument) {
	int eqIndex = argument.indexOf('=');
	String name = argument.substring(2, eqIndex);
	String value = argument.substring(eqIndex + 1);
	environment[name] = value;
	}

	setCategories(String argument) {
	List<String> categories = extractParameter(argument).split(',');
	Set<String> allowedCategories =
	LIBRARIES.values.map((x) => x.category).toSet();
	allowedCategories.remove('Shared');
	allowedCategories.remove('Internal');
	List<String> allowedCategoriesList =
	new List<String>.from(allowedCategories);
	allowedCategoriesList.sort();
	if (categories.contains('all')) {
	categories = allowedCategoriesList;
	} else {
	String allowedCategoriesString = allowedCategoriesList.join(', ');
	for (String category in categories) {
	if (!allowedCategories.contains(category)) {
	fail('Unsupported library category "$category", '
	'supported categories are: $allowedCategoriesString');
	}
	}
	}
	passThrough('--categories=${categories.join(",")}');
	}

	void handleThrowOnError(String argument) {
	diagnosticHandler.throwOnError = true;
	String parameter = extractParameter(argument, isOptionalArgument: true);
	if (parameter != null) {
	diagnosticHandler.throwOnErrorCount = int.parse(parameter);
	}
	}

	handleShortOptions(String argument) {
	var shortOptions = argument.substring(1).split("");
	for (var shortOption in shortOptions) {
	switch (shortOption) {
	case 'v':
	setVerbose(null);
	break;
	case 'h':
	case '?':
	wantHelp = true;
	break;
	case 'c':
	setCheckedMode('--enable-checked-mode');
	break;
	case 'm':
	implyCompilation('--minify');
	break;
	default:
	throw 'Internal error: "$shortOption" did not match';
	}
	}
	}

	List<String> arguments = <String>[];
	List<OptionHandler> handlers = <OptionHandler>[
	new OptionHandler('-[chvm?]+', handleShortOptions),
	new OptionHandler('--throw-on-error(?:=[0-9]+)?', handleThrowOnError),
	new OptionHandler('--suppress-warnings', (_) {
	diagnosticHandler.showWarnings = false;
	passThrough('--suppress-warnings');
	}),
	new OptionHandler('--suppress-hints',
	(_) => diagnosticHandler.showHints = false),
	new OptionHandler(
	'--output-type=dart\|--output-type=dart-multi\|--output-type=js',
	setOutputType),
	new OptionHandler('--verbose', setVerbose),
	new OptionHandler('--version', (_) => wantVersion = true),
	new OptionHandler('--library-root=.+', setLibraryRoot),
	new OptionHandler('--out=.+\|-o.*', setOutput, multipleArguments: true),
	new OptionHandler('--allow-mock-compilation', passThrough),
	new OptionHandler('--minify\|-m', implyCompilation),
	new OptionHandler('--preserve-uris', passThrough),
	new OptionHandler('--force-strip=.*', setStrip),
	new OptionHandler('--disable-diagnostic-colors',
	(_) => diagnosticHandler.enableColors = false),
	new OptionHandler('--enable-diagnostic-colors',
	(_) => diagnosticHandler.enableColors = true),
	new OptionHandler('--enable[_-]checked[_-]mode\|--checked',
	(_) => setCheckedMode('--enable-checked-mode')),
	new OptionHandler('--enable-concrete-type-inference',
	(_) => implyCompilation(
	'--enable-concrete-type-inference')),
	new OptionHandler('--trust-type-annotations',
	(_) => setTrustTypeAnnotations(
	'--trust-type-annotations')),
	new OptionHandler('--trust-primitives',
	(_) => setTrustPrimitives(
	'--trust-primitives')),
	new OptionHandler(r'--help\|/\?\|/h', (_) => wantHelp = true),
	new OptionHandler('--package-root=.+\|-p.+', setPackageRoot),
	new OptionHandler('--analyze-all', setAnalyzeAll),
	new OptionHandler('--analyze-only', setAnalyzeOnly),
	new OptionHandler('--analyze-signatures-only', setAnalyzeOnly),
	new OptionHandler('--disable-native-live-type-analysis', passThrough),
	new OptionHandler('--categories=.*', setCategories),
	new OptionHandler('--disable-type-inference', implyCompilation),
	new OptionHandler('--terse', passThrough),
	new OptionHandler('--dump-info', implyCompilation),
	new OptionHandler('--disallow-unsafe-eval',
	(_) => hasDisallowUnsafeEval = true),
	new OptionHandler('--show-package-warnings', passThrough),
	new OptionHandler('--csp', passThrough),
	new OptionHandler('--enable-experimental-mirrors', passThrough),
	new OptionHandler('--enable-async', setEnableAsync),
	new OptionHandler('--enable-enum', passThrough),
	new OptionHandler('-D.+=.*', addInEnvironment),

	// The following two options must come last.
	new OptionHandler('-.*', (String argument) {
	helpAndFail("Unknown option '$argument'.");
	}),
	new OptionHandler('.*', (String argument) {
	arguments.add(nativeToUriPath(argument));
	})
	];

	parseCommandLine(handlers, argv);
	if (wantHelp \|\| wantVersion) {
	helpAndExit(wantHelp, wantVersion, diagnosticHandler.verbose);
	}

	if (hasDisallowUnsafeEval) {
	String precompiledName =
	relativize(currentDirectory,
	RandomAccessFileOutputProvider.computePrecompiledUri(out),
	Platform.isWindows);
	helpAndFail("Option '--disallow-unsafe-eval' has been removed."
	" Instead, the compiler generates a file named"
	" '$precompiledName'.");
	}

	if (outputLanguage != OUTPUT_LANGUAGE_DART && stripArgumentSet) {
	helpAndFail("Option '--force-strip' may only be used with "
	"'--output-type=dart'.");
	}
	if (arguments.isEmpty) {
	helpAndFail('No Dart file specified.');
	}
	if (arguments.length > 1) {
	var extra = arguments.sublist(1);
	helpAndFail('Extra arguments: ${extra.join(" ")}');
	}

	if (checkedMode && trustTypeAnnotations) {
	helpAndFail("Option '--trust-type-annotations' may not be used in "
	"checked mode.");
	}

	Uri uri = currentDirectory.resolve(arguments[0]);
	if (packageRoot == null) {
	packageRoot = uri.resolve('./packages/');
	}

	if ((analyzeOnly \|\| analyzeAll) && !optionsImplyCompilation.isEmpty) {
	if (!analyzeOnly) {
	diagnosticHandler.info(
	"Option '--analyze-all' implies '--analyze-only'.",
	api.Diagnostic.INFO);
	}
	diagnosticHandler.info(
	"Options $optionsImplyCompilation indicate that output is expected, "
	"but compilation is turned off by the option '--analyze-only'.",
	api.Diagnostic.INFO);
	}
	if (analyzeAll) analyzeOnly = true;
	if (enableAsyncAwait && !analyzeOnly) {
	helpAndFail("Option '--enable-async' is currently only supported in "
	"combination with the '--analyze-only' option.");
	}

	diagnosticHandler.info('Package root is $packageRoot');

	options.add('--out=$out');
	options.add('--source-map=$sourceMapOut');

	RandomAccessFileOutputProvider outputProvider =
	new RandomAccessFileOutputProvider(
	out, sourceMapOut, onInfo: diagnosticHandler.info, onFailure: fail);

	compilationDone(String code) {
	if (analyzeOnly) return;
	if (code == null) {
	fail('Compilation failed.');
	}
	writeString(Uri.parse('$out.deps'),
	getDepsOutput(inputProvider.sourceFiles));
	diagnosticHandler.info(
	'Compiled ${inputProvider.dartCharactersRead} characters Dart '
	'-> ${outputProvider.totalCharactersWritten} characters '
	'$outputLanguage in '
	'${relativize(currentDirectory, out, Platform.isWindows)}');
	if (diagnosticHandler.verbose) {
	String input = uriPathToNative(arguments[0]);
	print('Dart file ($input) compiled to $outputLanguage.');
	print('Wrote the following files:');
	for (String filename in outputProvider.allOutputFiles) {
	print(" $filename");
	}
	} else if (!explicitOut) {
	String input = uriPathToNative(arguments[0]);
	String output = relativize(currentDirectory, out, Platform.isWindows);
	print('Dart file ($input) compiled to $outputLanguage: $output');
	}
	}

	return compileFunc(uri, libraryRoot, packageRoot,
	inputProvider, diagnosticHandler,
	options, outputProvider, environment)
	.then(compilationDone);
	}

	class AbortLeg {
	final message;
	AbortLeg(this.message);
	toString() => 'Aborted due to --throw-on-error: $message';
	}

	void writeString(Uri uri, String text) {
	if (uri.scheme != 'file') {
	fail('Unhandled scheme ${uri.scheme}.');
	}
	var file = new File(uri.toFilePath()).openSync(mode: FileMode.WRITE);
	file.writeStringSync(text);
	file.closeSync();
	}

	void fail(String message) {
	if (diagnosticHandler != null) {
	diagnosticHandler.diagnosticHandler(
	null, -1, -1, message, api.Diagnostic.ERROR);
	} else {
	print('Error: $message');
	}
	exitFunc(1);
	}

	Future compilerMain(List<String> arguments) {
	var root = uriPathToNative("/$LIBRARY_ROOT");
	arguments = <String>['--library-root=${Platform.script.toFilePath()}$root']
	..addAll(arguments);
	return compile(arguments);
	}

	void help() {
	// 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. 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).
	-m Generate minified output.
	-h Display this message (add -v for information about all options).''');
	}

	void verboseHelp() {
	print(r'''
	Usage: dart2js [options] dartfile

	Compiles Dart to JavaScript.

	Supported options:
	-o <file>, --out=<file>
	Generate the output into <file>.

	-c, --enable-checked-mode, --checked
	Insert runtime type checks and enable assertions (checked mode).

	-m, --minify
	Generate minified output.

	-h, /h, /?, --help
	Display this message (add -v for information about all options).

	-v, --verbose
	Display verbose information.

	-D<name>=<value>
	Define an environment variable.

	--version
	Display version information.

	-p<path>, --package-root=<path>
	Where to find packages, that is, "package:..." imports.

	--analyze-all
	Analyze all code. Without this option, the compiler only analyzes
	code that is reachable from [main]. This option implies --analyze-only.

	--analyze-only
	Analyze but do not generate code.

	--analyze-signatures-only
	Skip analysis of method bodies and field initializers. This option implies
	--analyze-only.

	--suppress-warnings
	Do not display any warnings.

	--suppress-hints
	Do not display any hints.

	--enable-diagnostic-colors
	Add colors to diagnostic messages.

	--terse
	Emit diagnostics without suggestions for how to get rid of the diagnosed
	problems.

	--show-package-warnings
	Show warnings and hints generated from packages.

	--preserve-uris
	Preserve the source URIs in the reflection data. Without this flag the
	`uri` getter for `LibraryMirror`s is mangled in minified mode.

	--csp
	Disables dynamic generation of code in the generated output. This is
	necessary to satisfy CSP restrictions (see http://www.w3.org/TR/CSP/).

	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.

	--library-root=<directory>
	Where to find the Dart platform libraries.

	--allow-mock-compilation
	Do not generate a call to main if either of the following
	libraries are used: dart:dom, dart:html dart:io.

	--enable-concrete-type-inference
	Enable experimental concrete type inference.

	--disable-native-live-type-analysis
	Disable the optimization that removes unused native types from dart:html
	and related libraries.

	--categories=<categories>
	A comma separated list of allowed library categories. The default
	is "Client". Possible categories can be seen by providing an
	unsupported category, for example, --categories=help. To enable
	all categories, use --categories=all.

	--dump-info
	Generates an out.info.json file with information about the generated code.
	You can inspect the generated file with the viewer at:
	https://dart-lang.github.io/dump-info-visualizer/

	'''.trim());
	}

	void helpAndExit(bool wantHelp, bool wantVersion, bool verbose) {
	if (wantVersion) {
	var version = (BUILD_ID == null)
	? '<non-SDK build>'
	: BUILD_ID;
	print('Dart-to-JavaScript compiler (dart2js) version: $version');
	}
	if (wantHelp) {
	if (verbose) {
	verboseHelp();
	} else {
	help();
	}
	}
	exitFunc(0);
	}

	void helpAndFail(String message) {
	help();
	print('');
	fail(message);
	}

	void main(List<String> arguments) {
	// Since the sdk/bin/dart2js script adds its own arguments in front of
	// user-supplied arguments we search for '--batch' at the end of the list.
	if (arguments.length > 0 && arguments.last == "--batch") {
	batchMain(arguments.sublist(0, arguments.length - 1));
	return;
	}
	internalMain(arguments);
	}

	var exitFunc = exit;
	var compileFunc = api.compile;

	Future internalMain(List<String> arguments) {
	onError(exception, trace) {
	try {
	print('The compiler crashed: $exception');
	} catch (ignored) {
	print('The compiler crashed: error while printing exception');
	}

	try {
	if (trace != null) {
	print(trace);
	}
	} finally {
	exitFunc(253); // 253 is recognized as a crash by our test scripts.
	}
	}

	try {
	return compilerMain(arguments).catchError(onError);
	} catch (exception, trace) {
	onError(exception, trace);
	return new Future.value();
	}
	}

	const _EXIT_SIGNAL = const Object();

	void batchMain(List<String> batchArguments) {
	int exitCode;
	exitFunc = (errorCode) {
	// Since we only throw another part of the compiler might intercept our
	// exception and try to exit with a different code.
	if (exitCode == 0) {
	exitCode = errorCode;
	}
	throw _EXIT_SIGNAL;
	};

	var stream = stdin.transform(UTF8.decoder).transform(new LineSplitter());
	var subscription;
	subscription = stream.listen((line) {
	new Future.sync(() {
	subscription.pause();
	exitCode = 0;
	if (line == null) exit(0);
	List<String> args = <String>[];
	args.addAll(batchArguments);
	args.addAll(splitLine(line, windows: Platform.isWindows));
	return internalMain(args);
	}).catchError((exception, trace) {
	if (!identical(exception, _EXIT_SIGNAL)) {
	exitCode = 253;
	}
	}).whenComplete(() {
	// The testing framework waits for a status line on stdout and
	// stderr before moving to the next test.
	if (exitCode == 0){
	print(">>> TEST OK");
	} else if (exitCode == 253) {
	print(">>> TEST CRASH");
	} else {
	print(">>> TEST FAIL");
	}
	stderr.writeln(">>> EOF STDERR");
	subscription.resume();
	});
	});
	}