React gracefully to a fully-.gitignored package.

lib/src/package.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 pub.package;
 
 import 'dart:io';
 
 import 'package:barback/barback.dart';
 import 'package:path/path.dart' as p;
@@ skipping 97 matching lines @@
     }));
   }
 
   /// Returns whether or not this package is in a Git repo.
   bool get _inGitRepo {
     if (_inGitRepoCache != null) return _inGitRepoCache;
 
     if (dir == null || !git.isInstalled) {
       _inGitRepoCache = false;
     } else {
-      try {
-        git.runSync(['rev-parse'], workingDir: dir);
-        _inGitRepoCache = true;
-      } on git.GitException catch (_) {
-        _inGitRepoCache = false;
-      }
+      // If the entire package directory is ignored, don't consider it part of a
+      // git repo. `git check-ignore` will return a status code of 0 for
+      // ignored, 1 for not ignored, and 128 for not a Git repo.
+      var result = runProcessSync(git.command, ['check-ignore', '--quiet', '.'],
+          workingDir: dir);
+      _inGitRepoCache = result.exitCode == 1;

[Bob Nystrom, 2015/08/26 23:19:02]

Instead of making git.command public, how about moving this blob of code into
git.dart as a "isDirectoryIgnored" function? I like the idea of all of the
command line argument shenanigans for git being localized to one file in pub.

[nweiz, 2015/08/27 19:04:33]

I'll do this if you want, but I think a lot of the command-line shenanigans are
already pretty exposed. The wrapper functions in the git library are pretty low
level; the only thing they really do, other than the git command, is throw a
nice exception if git fails. So adding such a high-level function would be kind
of at odds with the existing API.

     }
 
     return _inGitRepoCache;
   }
   bool _inGitRepoCache;
 
   /// Loads the package whose root directory is [packageDir].
   ///
   /// [name] is the expected name of that package (e.g. the name given in the
   /// dependency), or `null` if the package being loaded is the entrypoint
@@ skipping 301 matching lines @@
 
   bool operator ==(other) {
     // TODO(rnystrom): We're assuming here that we don't need to delve into the
     // description.
     return other is PackageDep &&
            other.name == name &&
            other.source == source &&
            other.constraint == constraint;
   }
 }