Merge branch 'jc/maint-co-track' into maint

* jc/maint-co-track:
  Enhance hold_lock_file_for_{update,append}() API
  demonstrate breakage of detached checkout with symbolic link HEAD
  Fix "checkout --track -b newbranch" on detached HEAD

1 files changed, 20 insertions, 6 deletions

diff --git a/t/t7201-co.sh b/t/t7201-co.sh
index 0679abd29..c9abed6a2 100755
--- a/t/t7201-co.sh
+++ b/t/t7201-co.sh
@@ -330,12 +330,26 @@ test_expect_success \
     test "$(git config branch.track2.merge)"
     git config branch.autosetupmerge false'
 
-test_expect_success \
-    'checkout w/--track from non-branch HEAD fails' '
-    git checkout -b delete-me master &&
-    rm .git/refs/heads/delete-me &&
-    test refs/heads/delete-me = "$(git symbolic-ref HEAD)" &&
-    test_must_fail git checkout --track -b track'
+test_expect_success 'checkout w/--track from non-branch HEAD fails' '
+    git checkout master^0 &&
+    test_must_fail git symbolic-ref HEAD &&
+    test_must_fail git checkout --track -b track &&
+    test_must_fail git rev-parse --verify track &&
+    test_must_fail git symbolic-ref HEAD &&
+    test "z$(git rev-parse master^0)" = "z$(git rev-parse HEAD)"
+'
+
+test_expect_success 'detach a symbolic link HEAD' '
+    git checkout master &&
+    git config --bool core.prefersymlinkrefs yes &&
+    git checkout side &&
+    git checkout master &&
+    it=$(git symbolic-ref HEAD) &&
+    test "z$it" = zrefs/heads/master &&
+    here=$(git rev-parse --verify refs/heads/master) &&
+    git checkout side^ &&
+    test "z$(git rev-parse --verify refs/heads/master)" = "z$here"
+'
 
 test_expect_success 'checkout an unmerged path should fail' '
 	rm -f .git/index &&