- Added test and fix when in detached head.

merge-conflict

@@ -2,7 +2,7 @@
 set -eu
 
 dest="${1:-master}"
-current="$(git symbolic-ref --short HEAD)"
+current="$(git symbolic-ref --short HEAD)" || exit 0  # Detached head.
 
 [ "$current" != "$dest" ] || exit 0
 

tests/merge-conflict.bats

@@ -25,6 +25,12 @@ export repo="$BATS_TMPDIR/testrepo"
     fi
 }
 
+@test "Detached head" {
+    cd "$repo"
+    git checkout "$(git rev-parse HEAD)"
+    merge-conflict
+}
+
 @test "Same branch" {
     cd "$repo"
     git checkout master || true