git-prompt: work under set -u

newren · gitster · commit 5c0cbdb107c5 · 2021-05-13T15:50:26.000+09:00
Commit afda36d ("git-prompt: include sparsity state as well", 2020-06-21) added the use of some variables to control how to show sparsity state in the git prompt, but implicitly assumed that undefined variables would be treated as the empty string. This breaks users who run under 'set -u'; fix the code to be more explicit. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
@@ -433,8 +433,8 @@ __git_ps1 ()
 	fi
 
 	local sparse=""
-	if [ -z "${GIT_PS1_COMPRESSSPARSESTATE}" ] &&
-	   [ -z "${GIT_PS1_OMITSPARSESTATE}" ] &&
+	if [ -z "${GIT_PS1_COMPRESSSPARSESTATE-}" ] &&
+	   [ -z "${GIT_PS1_OMITSPARSESTATE-}" ] &&
 	   [ "$(git config --bool core.sparseCheckout)" = "true" ]; then
 		sparse="|SPARSE"
 	fi
@@ -543,7 +543,7 @@ __git_ps1 ()
 			u="%${ZSH_VERSION+%}"
 		fi
 
-		if [ -n "${GIT_PS1_COMPRESSSPARSESTATE}" ] &&
+		if [ -n "${GIT_PS1_COMPRESSSPARSESTATE-}" ] &&
 		   [ "$(git config --bool core.sparseCheckout)" = "true" ]; then
 			h="?"
 		fi
