Experimental analyzer front-end baby-steps.

pkg/analyzer-experimental/bin/analyzer.dart

Index: pkg/analyzer-experimental/bin/analyzer.dart
===================================================================
--- pkg/analyzer-experimental/bin/analyzer.dart	(revision 0)
+++ pkg/analyzer-experimental/bin/analyzer.dart	(revision 0)
@@ -0,0 +1,46 @@
+#!/usr/bin/env dart
+
+// 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.
+
+/** The entry point for the analyzer */

[Bob Nystrom, 2013/01/18 22:25:22]

Make full sentence: "."

[pquitslund, 2013/01/22 18:31:53]

Done.

+library analyzer;
+
+//import 'dart:async';
+import 'dart:io';
+
+import 'package:analyzer/options.dart';
+
+//Exit status codes

[Bob Nystrom, 2013/01/18 22:25:22]

Space after "//" and "." at the end.

[pquitslund, 2013/01/22 18:31:53]

Done.

+const OK_EXIT = 0;
+const ERROR_EXIT = 1;
+
+void main() {
+  run(new Options().arguments).then((result) {
+    exit(result.error ? ERROR_EXIT : OK_EXIT);
+  });
+}
+
+/** The result of an analysis. */
+class AnalysisResult {
+  final bool error;
+  AnalysisResult.forFailure() : error = true;
+  AnalysisResult.forSuccess() : error = false;
+}
+
+
+/**
+ * Runs the dart analyzer with the command-line options in [args].
+ * See [CommandLineOptions] for a list of valid arguments.
+ */
+Future<AnalysisResult> run(List<String> args) {
+
+  var options = CommandLineOptions.parse(args);
+  if (options == null) {
+    return new Future.immediate(new AnalysisResult.forFailure());

[Bob Nystrom, 2013/01/18 22:25:22]

I would probably separate *analysis* failure from argument parsing failure. You
can throw a FormatException from this method and then "catch" it in main() using
catchError() on Future, like:

   run(new Options().arguments).then((result) {
     ...
   }).catchError((error) {
     if (error.error is FormatException) {
       ...
     }
   });

[pquitslund, 2013/01/22 18:31:53]

Since I've already handled a FormatException in parse() (in order to print
usage), throwing another feels odd here unless, that is, I want different exit
codes for analysis and format errors, which I just might.  Anyway, I'm on the
fence enough that I'll probably sit on this for now.   But thanks!

+  }
+
+  //TODO(pquitslund): call out to analyzer...
+
+}