[PATCH v2] git-prompt.sh: add submodule indicator

[PATCH v2] git-prompt.sh: add submodule indicator

[Benjamin Fuchs]

Hi everyone again,
I guess this time I'm rerolling my patch the right way.
Thanks again Gábor for your feedback.
And thanks to Junio for being patient and explaining the reroll workflow 
Greeting,
Benjamin

Benjamin Fuchs (1):
  git-prompt.sh: add submodule indicator

 contrib/completion/git-prompt.sh | 40 ++++++++++++++++++++++++++-
 t/t9903-bash-prompt.sh           | 59 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 1 deletion(-)

-- 
2.7.4

[PATCH v2] git-prompt.sh: add submodule indicator

[Benjamin Fuchs]

I expirienced that working with submodules can be confusing. A submodule can be
anywhere in your parent git repository. While walking through the parent
repository it would be good to have a reminder to know when you entered a
submodule.

This new indicator will show if you are in a submodule. The new prompt will look
like this: (sub:master). If the currently checked out submodule commit does not
match the SHA-1 found in the index of the containing repository a "+" will be
prepended (+sub:master). Adding a new optional env variable for the new feature.

Signed-off-by: Benjamin Fuchs <email@benjaminfuchs.de>
---
 contrib/completion/git-prompt.sh | 40 ++++++++++++++++++++++++++-
 t/t9903-bash-prompt.sh           | 59 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 1 deletion(-)

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index 97eacd7..9a0c4af 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -93,6 +93,13 @@
 # directory is set up to be ignored by git, then set
 # GIT_PS1_HIDE_IF_PWD_IGNORED to a nonempty value. Override this on the
 # repository level by setting bash.hideIfPwdIgnored to "false".
+#
+# If you would like __git_ps1 to indicate that you are in a submodule,
+# set GIT_PS1_SHOWSUBMODULE to a nonempty value. In this case the name
+# of the submodule will be prepended to the branch name (e.g. module:master).
+# If you set GIT_PS1_SHOWDIRTYSTATE to a nonempty value, the name will be
+# prepended by "+" if the currently checked out submodule commit does not
+# match the SHA-1 found in the index of the containing repository.
 
 # check whether printf supports -v
 __git_printf_supports_v=
@@ -284,6 +291,32 @@ __git_eread ()
 	test -r "$f" && read "$@" <"$f"
 }
 
+# __git_ps1_submodule
+# Requires the git dir set in $g by the caller.
+# Returns the name of the submodule in $sub if we are currently inside one.
+# The name will be prepended by "+" if the currently checked out submodule commit
+# does not match the SHA-1 found in the index of the containing repository.
+# NOTE: git_dir looks like in a ...
+# - submodule:	"GIT_PARENT/.git/modules/PATH_TO_SUBMODULE"
+# - parent:	"GIT_PARENT/.git" (exception "." in .git)
+__git_ps1_submodule ()
+{
+	local git_dir="$g"
+	local submodule_name="$(basename "$git_dir")"
+	if [ "$submodule_name" != ".git" ] && [ "$submodule_name" != "." ]; then
+		local status=""
+		if [ -n "${GIT_PS1_SHOWDIRTYSTATE-}" ] &&
+		   [ "$(git config --bool bash.showDirtyState)" != "false" ]
+		then
+			local parent_top="${git_dir%.git*}"
+			local submodule_top="${git_dir#*modules/}"
+			git -C "$parent_top" diff --no-ext-diff --ignore-submodules=dirty --quiet -- "$submodule_top" 2>/dev/null || status="+"
+		fi
+
+		sub="$status$submodule_name:"
+	fi
+}
+
 # __git_ps1 accepts 0 or 1 arguments (i.e., format string)
 # when called from PS1 using command substitution
 # in this mode it prints text to add to bash PS1 prompt (includes branch name)
@@ -513,8 +546,13 @@ __git_ps1 ()
 		b="\${__git_ps1_branch_name}"
 	fi
 
+	local sub=""
+	if [ -n "${GIT_PS1_SHOWSUBMODULE-}" ]; then
+		__git_ps1_submodule
+	fi
+
 	local f="$w$i$s$u"
-	local gitstring="$c$b${f:+$z$f}$r$p"
+	local gitstring="$c$sub$b${f:+$z$f}$r$p"
 
 	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 97c9b32..ac82c99 100755
--- a/t/t9903-bash-prompt.sh
+++ b/t/t9903-bash-prompt.sh
@@ -16,9 +16,22 @@ c_lblue='\\[\\e[1;34m\\]'
 c_clear='\\[\\e[0m\\]'
 
 test_expect_success 'setup for prompt tests' '
+	mkdir .subrepo &&
+	(cd .subrepo &&
+		git init &&
+		echo 1 >file &&
+		git add file &&
+		git commit -m initial &&
+		git checkout -b dirty &&
+		echo 2 >file &&
+		git commit -m "dirty branch" file
+	) &&
 	git init otherrepo &&
 	echo 1 >file &&
 	git add file &&
+	git submodule add ./.subrepo sub &&
+	git -C sub checkout master &&
+	git add sub &&
 	test_tick &&
 	git commit -m initial &&
 	git tag -a -m msg1 t1 &&
@@ -755,4 +768,50 @@ test_expect_success 'prompt - hide if pwd ignored - inside gitdir (stderr)' '
 	test_cmp expected "$actual"
 '
 
+test_expect_success 'prompt - submodule indicator' '
+	printf " (sub:master)" >expected &&
+	(
+		cd sub &&
+		GIT_PS1_SHOWSUBMODULE=y &&
+		__git_ps1 >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success 'prompt - submodule indicator - disabled' '
+	printf " (master)" >expected &&
+	(
+		cd sub &&
+		GIT_PS1_SHOWSUBMODULE= &&
+		__git_ps1 >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success 'prompt - submodule indicator - dirty status indicator' '
+	printf " (+sub:dirty)" >expected &&
+	git -C sub checkout dirty &&
+	test_when_finished "git -C sub checkout master" &&
+	(
+		cd sub &&
+		GIT_PS1_SHOWSUBMODULE=y &&
+		GIT_PS1_SHOWDIRTYSTATE=y &&
+		__git_ps1 >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
+test_expect_success 'prompt - submodule indicator - dirty status indicator disabled' '
+	printf " (sub:dirty)" >expected &&
+	git -C sub checkout dirty &&
+	test_when_finished "git -C sub checkout master" &&
+	(
+		cd sub &&
+		GIT_PS1_SHOWSUBMODULE=y &&
+		GIT_PS1_SHOWDIRTYSTATE= &&
+		__git_ps1 >"$actual"
+	) &&
+	test_cmp expected "$actual"
+'
+
 test_done
-- 
2.7.4