improve detecting upstream information

lib/hub/context.rb

@@ -81,9 +81,17 @@ def current_branch
       GIT_CONFIG['symbolic-ref -q HEAD']
     end
 
+    def upstream_ref(branch)
+      GIT_CONFIG["name-rev #{branch}@{upstream} --name-only --refs='refs/remotes/*' --no-undefined"]
+    end
+
+    def upstream_remote(branch)
+      upstream_ref(branch) =~ %r{^remotes/(.+?)/} and $1
+    end
+
     def tracked_branch
-      branch = current_branch && tracked_for(current_branch)
-      normalize_branch(branch) if branch
+      branch = current_branch && upstream_ref(current_branch)
+      branch.sub(%r{^remotes/(.+?)/}, '') if branch
     end
 
     def remotes
@@ -98,7 +106,7 @@ def remotes_group(name)
 
     def current_remote
       return if remotes.empty?
-      (current_branch && remote_for(current_branch)) || default_remote
+      (current_branch && upstream_remote(current_branch)) || default_remote
     end
 
     def default_remote
@@ -109,14 +117,6 @@ def normalize_branch(branch)
       branch.sub('refs/heads/', '')
     end
 
-    def remote_for(branch)
-      GIT_CONFIG['config branch.%s.remote' % normalize_branch(branch)]
-    end
-
-    def tracked_for(branch)
-      GIT_CONFIG['config branch.%s.merge' % normalize_branch(branch)]
-    end
-
     def http_clone?
       GIT_CONFIG['config --bool hub.http-clone'] == 'true'
     end

test/hub_test.rb

@@ -43,8 +43,7 @@ def setup
       'config github.token'  => 'abc123',
       'config --get-all remote.origin.url' => 'git://github.com/defunkt/hub.git',
       'config --get-all remote.mislav.url' => 'git://github.com/mislav/hub.git',
-      'config branch.master.remote'  => 'origin',
-      'config branch.master.merge'   => 'refs/heads/master',
+      "name-rev refs/heads/master@{upstream} --name-only --refs='refs/remotes/*' --no-undefined" => 'remotes/origin/master',
       'config --bool hub.http-clone' => 'false',
       'rev-parse --git-dir' => '.git'
     )
@@ -700,7 +699,7 @@ def test_hub_compare_tracking_nothing
 
   def test_hub_compare_tracking_branch
     stub_branch('refs/heads/feature')
-    stub_tracking('feature', 'mislav', 'refs/heads/experimental')
+    stub_tracking('feature', 'mislav', 'experimental')
 
     assert_command "compare",
       "open https://github.com/mislav/hub/compare/experimental"
@@ -774,7 +773,7 @@ def test_hub_browse_subpage
 
   def test_hub_browse_on_branch
     stub_branch('refs/heads/feature')
-    stub_tracking('feature', 'mislav', 'refs/heads/experimental')
+    stub_tracking('feature', 'mislav', 'experimental')
 
     assert_command "browse resque", "open https://github.com/tpw/resque"
     assert_command "browse resque commits",
@@ -804,7 +803,7 @@ def test_hub_browse_no_tracking
 
   def test_hub_browse_no_tracking_on_branch
     stub_branch('refs/heads/feature')
-    stub_tracking('feature', nil, nil)
+    stub_tracking_nothing('feature')
     assert_command "browse", "open https://github.com/defunkt/hub"
   end
 
@@ -909,8 +908,8 @@ def stub_branch(value)
     end
 
     def stub_tracking(from, remote_name, remote_branch)
-      @git["config branch.#{from}.remote"] = remote_name
-      @git["config branch.#{from}.merge"] = remote_branch
+      value = remote_branch ? "remotes/#{remote_name}/#{remote_branch}" : nil
+      @git["name-rev refs/heads/#{from}@{upstream} --name-only --refs='refs/remotes/*' --no-undefined"] = value
     end
 
     def stub_tracking_nothing