React gracefully to a fully-.gitignored package.

lib/src/package.dart

Index: lib/src/package.dart
diff --git a/lib/src/package.dart b/lib/src/package.dart
index 28af288d66e38e29e11a25a44a410d2e59a7bcc6..1a192c400c3e1b37666e92952bb78ab84ce1afb5 100644
--- a/lib/src/package.dart
+++ b/lib/src/package.dart
@@ -115,12 +115,12 @@ class Package {
     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;