Include revision hash in Source::Git#to_sshow-git-rev

This effectively changes the output of commands that use Source::Git#to_s
(ie. `bundle install`). For example:

    Using rack 1.0.0 from git@github.com:rack/rack.git (at master@574b147)

Closes #3433.

1 files changed, 2 insertions, 2 deletions

diff --git a/spec/update/git_spec.rb b/spec/update/git_spec.rb
index 5fd587dbba..f61e561179 100644
--- a/spec/update/git_spec.rb
+++ b/spec/update/git_spec.rb
@@ -32,7 +32,7 @@ describe "bundle update" do
       G
 
       bundle "update rails"
-      expect(out).to include("Using activesupport 3.0 from #{lib_path("rails")} (at master)")
+      expect(out).to include("Using activesupport 3.0 from #{lib_path("rails")} (at master@#{revision_for(lib_path("rails"))[0..6]})")
       should_be_installed "rails 3.0", "activesupport 3.0"
     end
 
@@ -229,7 +229,7 @@ describe "bundle update" do
       G
 
       bundle "update"
-      expect(out).to include("Using rails 3.0 (was 2.3.2) from #{lib_path("rails")} (at master)")
+      expect(out).to include("Using rails 3.0 (was 2.3.2) from #{lib_path("rails")} (at master@#{revision_for(lib_path("rails"))[0..6]})")
     end
   end