[PATCH v3] git-prompt: show presence of unresolved conflicts at command prompt

["Justin Donnelly via GitGitGadget" <gitgitgadget@gmail.com>]

From: Justin Donnelly <justinrdonnelly@gmail.com>

If GIT_PS1_SHOWCONFLICTSTATE is set to "yes", show the word "CONFLICT"
on the command prompt when there are unresolved conflicts.

Example prompt: (main|CONFLICT)

Signed-off-by: Justin Donnelly <justinrdonnelly@gmail.com>
---
    Show 'CONFLICT' indicator at command prompt
    
    This patch adds functionality for bash/zsh to show "CONFLICT" on the
    prompt in cases where there are unresolved conflicts. The feature is
    only enabled after setting an environment variable.
    
    The conflict state is determined by running git ls-files --unmerged. In
    my testing, the performance was very good. It took around 0.01 seconds
    to run git ls-files --unmerged regardless of the number of conflicts, or
    their depth, even on very large projects (Linux kernel). I got similar
    performance running git diff --cached --quiet --diff-filter=U.
    
    ------------------------------------------------------------------------
    
    Changes since v2:
    
     * There is now a single new test focused explicitly on this feature
       instead of making copies of existing tests and modifying them.
    
    Changes since v1:
    
     * This feature is now disabled by default.
     * Created new tests for conflict state (instead of modifying existing
       tests).

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1302%2Fjustinrdonnelly%2Fconflict-indicator-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1302/justinrdonnelly/conflict-indicator-v3
Pull-Request: https://github.com/gitgitgadget/git/pull/1302

Range-diff vs v2:

 1:  7154d695426 ! 1:  2ea5c403924 git-prompt: show presence of unresolved conflicts at command prompt
     @@ contrib/completion/git-prompt.sh: __git_ps1 ()
       		if [ "${__git_printf_supports_v-}" != yes ]; then
      
       ## t/t9903-bash-prompt.sh ##
     -@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - rebase merge' '
     - 	test_when_finished "git checkout main" &&
     - 	test_must_fail git rebase --merge b1 b2 &&
     - 	test_when_finished "git rebase --abort" &&
     --	__git_ps1 >"$actual" &&
     -+	(
     -+		sane_unset GIT_PS1_SHOWCONFLICTSTATE &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     -+	test_cmp expected "$actual"
     -+'
     -+
     -+test_expect_success 'prompt - rebase merge conflict' '
     -+	printf " (b2|REBASE 1/3|CONFLICT)" >expected &&
     -+	git checkout b2 &&
     -+	test_when_finished "git checkout main" &&
     -+	test_must_fail git rebase --merge b1 b2 &&
     -+	test_when_finished "git rebase --abort" &&
     -+	(
     -+		GIT_PS1_SHOWCONFLICTSTATE="yes" &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     - 	test_cmp expected "$actual"
     - '
     - 
     -@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - rebase am' '
     - 	test_when_finished "git checkout main" &&
     - 	test_must_fail git rebase --apply b1 b2 &&
     - 	test_when_finished "git rebase --abort" &&
     --	__git_ps1 >"$actual" &&
     -+	(
     -+		sane_unset GIT_PS1_SHOWCONFLICTSTATE &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     -+	test_cmp expected "$actual"
     -+'
     -+
     -+test_expect_success 'prompt - rebase am conflict' '
     -+	printf " (b2|REBASE 1/3|CONFLICT)" >expected &&
     -+	git checkout b2 &&
     -+	test_when_finished "git checkout main" &&
     -+	test_must_fail git rebase --apply b1 b2 &&
     -+	test_when_finished "git rebase --abort" &&
     -+	(
     -+		GIT_PS1_SHOWCONFLICTSTATE="yes" &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     - 	test_cmp expected "$actual"
     - '
     - 
     -@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - merge' '
     - 	test_when_finished "git checkout main" &&
     - 	test_must_fail git merge b2 &&
     - 	test_when_finished "git reset --hard" &&
     --	__git_ps1 >"$actual" &&
     -+	(
     -+		sane_unset GIT_PS1_SHOWCONFLICTSTATE &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     -+	test_cmp expected "$actual"
     -+'
     -+
     -+test_expect_success 'prompt - merge conflict' '
     -+	printf " (b1|MERGING|CONFLICT)" >expected &&
     -+	git checkout b1 &&
     -+	test_when_finished "git checkout main" &&
     -+	test_must_fail git merge b2 &&
     -+	test_when_finished "git reset --hard" &&
     -+	(
     -+		GIT_PS1_SHOWCONFLICTSTATE="yes" &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     - 	test_cmp expected "$actual"
     - '
     - 
     -@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - cherry-pick' '
     - 	printf " (main|CHERRY-PICKING)" >expected &&
     - 	test_must_fail git cherry-pick b1 b1^ &&
     - 	test_when_finished "git cherry-pick --abort" &&
     --	__git_ps1 >"$actual" &&
     -+	(
     -+		sane_unset GIT_PS1_SHOWCONFLICTSTATE &&
     -+		__git_ps1 >"$actual"
     -+	) &&
     - 	test_cmp expected "$actual" &&
     - 	git reset --merge &&
     - 	test_must_fail git rev-parse CHERRY_PICK_HEAD &&
     -@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - cherry-pick' '
     +@@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - hide if pwd ignored - inside gitdir' '
       	test_cmp expected "$actual"
       '
       
     -+test_expect_success 'prompt - cherry-pick conflict' '
     -+	printf " (main|CHERRY-PICKING|CONFLICT)" >expected &&
     -+	test_must_fail git cherry-pick b1 b1^ &&
     -+	test_when_finished "git cherry-pick --abort" &&
     ++test_expect_success 'prompt - conflict indicator' '
     ++	printf " (main|CONFLICT)" >expected &&
     ++	echo "stash" >file &&
     ++	git stash &&
     ++	test_when_finished "git stash drop" &&
     ++	echo "commit" >file &&
     ++	git commit -m "commit" file &&
     ++	test_when_finished "git reset --hard HEAD~" &&
     ++	test_must_fail git stash apply &&
      +	(
      +		GIT_PS1_SHOWCONFLICTSTATE="yes" &&
      +		__git_ps1 >"$actual"
     @@ t/t9903-bash-prompt.sh: test_expect_success 'prompt - cherry-pick' '
      +	test_cmp expected "$actual"
      +'
      +
     - test_expect_success 'prompt - revert' '
     - 	printf " (main|REVERTING)" >expected &&
     - 	test_must_fail git revert b1^ b1 &&
     + test_done


 contrib/completion/git-prompt.sh | 12 +++++++++++-
 t/t9903-bash-prompt.sh           | 16 ++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index 1435548e004..57972c2845c 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -84,6 +84,10 @@
 # single '?' character by setting GIT_PS1_COMPRESSSPARSESTATE, or omitted
 # by setting GIT_PS1_OMITSPARSESTATE.
 #
+# If you would like to see a notification on the prompt when there are
+# unresolved conflicts, set GIT_PS1_SHOWCONFLICTSTATE to "yes". The
+# prompt will include "|CONFLICT".
+#
 # If you would like to see more information about the identity of
 # commits checked out as a detached HEAD, set GIT_PS1_DESCRIBE_STYLE
 # to one of these values:
@@ -508,6 +512,12 @@ __git_ps1 ()
 		r="$r $step/$total"
 	fi
 
+	local conflict="" # state indicator for unresolved conflicts
+	if [[ "${GIT_PS1_SHOWCONFLICTSTATE}" == "yes" ]] &&
+	   [[ $(git ls-files --unmerged 2>/dev/null) ]]; then
+		conflict="|CONFLICT"
+	fi
+
 	local w=""
 	local i=""
 	local s=""
@@ -572,7 +582,7 @@ __git_ps1 ()
 	fi
 
 	local f="$h$w$i$s$u$p"
-	local gitstring="$c$b${f:+$z$f}${sparse}$r${upstream}"
+	local gitstring="$c$b${f:+$z$f}${sparse}$r${upstream}${conflict}"
 
 	if [ $pcmode = yes ]; then
 		if [ "${__git_printf_supports_v-}" != yes ]; then
diff --git a/t/t9903-bash-prompt.sh b/t/t9903-bash-prompt.sh
index 6a30f5719c3..d459fae6551 100755
--- a/t/t9903-bash-prompt.sh
+++ b/t/t9903-bash-prompt.sh
@@ -759,4 +759,20 @@ test_expect_success 'prompt - hide if pwd ignored - inside gitdir' '
 	test_cmp expected "$actual"
 '
 
+test_expect_success 'prompt - conflict indicator' '
+	printf " (main|CONFLICT)" >expected &&
+	echo "stash" >file &&
+	git stash &&
+	test_when_finished "git stash drop" &&
+	echo "commit" >file &&
+	git commit -m "commit" file &&
+	test_when_finished "git reset --hard HEAD~" &&
+	test_must_fail git stash apply &&
+	(
+		GIT_PS1_SHOWCONFLICTSTATE="yes" &&
+		__git_ps1 >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
 test_done

base-commit: 9bf691b78cf906751e65d65ba0c6ffdcd9a5a12c
-- 
gitgitgadget