tap: support --full even if installed

Makes `tap` re-runnable and unshallows when requested with `--full`.
Tapping with a different URL raises an exception.

The homebrew/core tap cannot be untapped with `untap` so running
`brew tap --full homebrew/core` is now a built-in way to get a full
clone of this tap without resorting to workarounds.

Closes #17.

Signed-off-by: ilovezfs <ilovezfs@icloud.com>

1 files changed, 26 insertions, 1 deletions

diff --git a/Library/Homebrew/test/test_tap.rb b/Library/Homebrew/test/test_tap.rb
index fa0602e94..0b2671698 100644
--- a/Library/Homebrew/test/test_tap.rb
+++ b/Library/Homebrew/test/test_tap.rb
@@ -164,7 +164,32 @@ class TapTest < Homebrew::TestCase
   end
 
   def test_install_tap_already_tapped_error
-    assert_raises(TapAlreadyTappedError) { @tap.install }
+    setup_git_repo
+    already_tapped_tap = Tap.new("Homebrew", "foo")
+    assert_equal true, already_tapped_tap.installed?
+    assert_raises(TapAlreadyTappedError) { already_tapped_tap.install }
+  end
+
+  def test_install_tap_remote_match_already_tapped_error
+    setup_git_repo
+    already_tapped_tap = Tap.new("Homebrew", "foo")
+    assert_equal true, already_tapped_tap.installed?
+    right_remote = "#{@tap.remote}"
+    assert_raises(TapAlreadyTappedError) { already_tapped_tap.install :clone_target => right_remote }
+  end
+
+  def test_install_tap_remote_mismatch_error
+    setup_git_repo
+    already_tapped_tap = Tap.new("Homebrew", "foo")
+    assert_equal true, already_tapped_tap.installed?
+    wrong_remote = "#{@tap.remote}-oops"
+    assert_raises(TapRemoteMismatchError) { already_tapped_tap.install :clone_target => wrong_remote }
+  end
+
+  def test_install_tap_already_unshallow_error
+    setup_git_repo
+    already_tapped_tap = Tap.new("Homebrew", "foo")
+    assert_raises(TapAlreadyUnshallowError) { already_tapped_tap.install :full_clone => true }
   end
 
   def test_uninstall_tap_unavailable_error