Merge branch 'jl/submodule-diff'

* jl/submodule-diff:
  Performance optimization for detection of modified submodules
  git status: Show uncommitted submodule changes too when enabled
  Teach diff that modified submodule directory is dirty
  Show submodules as modified when they contain a dirty work tree

4 files changed, 154 insertions, 19 deletions

diff --git a/t/t4027-diff-submodule.sh b/t/t4027-diff-submodule.sh
index 5cf8924b21..83c1914771 100755
--- a/t/t4027-diff-submodule.sh
+++ b/t/t4027-diff-submodule.sh
@@ -32,7 +32,8 @@ test_expect_success setup '
 		cd sub &&
 		git rev-list HEAD
 	) &&
-	echo ":160000 160000 $3 $_z40 M	sub" >expect
+	echo ":160000 160000 $3 $_z40 M	sub" >expect &&
+	subtip=$3 subprev=$2
 '
 
 test_expect_success 'git diff --raw HEAD' '
@@ -50,6 +51,87 @@ test_expect_success 'git diff-files --raw' '
 	test_cmp expect actual.files
 '
 
+expect_from_to () {
+	printf "%sSubproject commit %s\n+Subproject commit %s\n" \
+		"-" "$1" "$2"
+}
+
+test_expect_success 'git diff HEAD' '
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subtip $subprev &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (work tree)' '
+	echo >>sub/world &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subtip $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (index)' '
+	(
+		cd sub &&
+		git reset --hard &&
+		echo >>world &&
+		git add world
+	) &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subtip $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (untracked)' '
+	(
+		cd sub &&
+		git reset --hard &&
+		git clean -qfdx &&
+		>cruft
+	) &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subtip $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (work tree, refs match)' '
+	git commit -m "x" sub &&
+	echo >>sub/world &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subprev $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (index, refs match)' '
+	(
+		cd sub &&
+		git reset --hard &&
+		echo >>world &&
+		git add world
+	) &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subprev $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
+test_expect_success 'git diff HEAD with dirty submodule (untracked, refs match)' '
+	(
+		cd sub &&
+		git reset --hard &&
+		git clean -qfdx &&
+		>cruft
+	) &&
+	git diff HEAD >actual &&
+	sed -e "1,/^@@/d" actual >actual.body &&
+	expect_from_to >expect.body $subprev $subprev-dirty &&
+	test_cmp expect.body actual.body
+'
+
 test_expect_success 'git diff (empty submodule dir)' '
 	: >empty &&
 	rm -rf sub/* sub/.git &&
diff --git a/t/t7401-submodule-summary.sh b/t/t7401-submodule-summary.sh
index 6cc16c39fe..d3c039f724 100755
--- a/t/t7401-submodule-summary.sh
+++ b/t/t7401-submodule-summary.sh
@@ -213,7 +213,7 @@ EOF
 test_expect_success '--for-status' "
     git submodule summary --for-status HEAD^ >actual &&
     test_cmp actual - <<EOF
-# Modified submodules:
+# Submodule changes to be committed:
 #
 # * sm1 $head6...0000000:
 #
diff --git a/t/t7506-status-submodule.sh b/t/t7506-status-submodule.sh
index 3ca17abad1..253c334319 100755
--- a/t/t7506-status-submodule.sh
+++ b/t/t7506-status-submodule.sh
@@ -5,34 +5,87 @@ test_description='git status for submodule'
 . ./test-lib.sh
 
 test_expect_success 'setup' '
-	test_create_repo sub
-	cd sub &&
-	: >bar &&
-	git add bar &&
-	git commit -m " Add bar" &&
-	cd .. &&
-	git add sub &&
+	test_create_repo sub &&
+	(
+		cd sub &&
+		: >bar &&
+		git add bar &&
+		git commit -m " Add bar" &&
+		: >foo &&
+		git add foo &&
+		git commit -m " Add foo"
+	) &&
+	echo output > .gitignore &&
+	git add sub .gitignore &&
 	git commit -m "Add submodule sub"
 '
 
 test_expect_success 'status clean' '
-	git status |
-	grep "nothing to commit"
+	git status >output &&
+	grep "nothing to commit" output
 '
+
 test_expect_success 'commit --dry-run -a clean' '
-	git commit --dry-run -a |
-	grep "nothing to commit"
+	test_must_fail git commit --dry-run -a >output &&
+	grep "nothing to commit" output
+'
+
+test_expect_success 'status with modified file in submodule' '
+	(cd sub && git reset --hard) &&
+	echo "changed" >sub/foo &&
+	git status >output &&
+	grep "modified:   sub" output
+'
+
+test_expect_success 'status with modified file in submodule (porcelain)' '
+	(cd sub && git reset --hard) &&
+	echo "changed" >sub/foo &&
+	git status --porcelain >output &&
+	diff output - <<-\EOF
+	 M sub
+	EOF
+'
+
+test_expect_success 'status with added file in submodule' '
+	(cd sub && git reset --hard && echo >foo && git add foo) &&
+	git status >output &&
+	grep "modified:   sub" output
+'
+
+test_expect_success 'status with added file in submodule (porcelain)' '
+	(cd sub && git reset --hard && echo >foo && git add foo) &&
+	git status --porcelain >output &&
+	diff output - <<-\EOF
+	 M sub
+	EOF
+'
+
+test_expect_success 'status with untracked file in submodule' '
+	(cd sub && git reset --hard) &&
+	echo "content" >sub/new-file &&
+	git status >output &&
+	grep "modified:   sub" output
+'
+
+test_expect_success 'status with untracked file in submodule (porcelain)' '
+	git status --porcelain >output &&
+	diff output - <<-\EOF
+	 M sub
+	EOF
 '
+
 test_expect_success 'rm submodule contents' '
 	rm -rf sub/* sub/.git
 '
+
 test_expect_success 'status clean (empty submodule dir)' '
-	git status |
-	grep "nothing to commit"
+	git status >output &&
+	grep "nothing to commit" output
 '
+
 test_expect_success 'status -a clean (empty submodule dir)' '
-	git commit --dry-run -a |
-	grep "nothing to commit"
+	test_must_fail git commit --dry-run -a >output &&
+	grep "nothing to commit" output
 '
 
 test_done
diff --git a/t/t7508-status.sh b/t/t7508-status.sh
index cf67fe3a4a..556d0faa77 100755
--- a/t/t7508-status.sh
+++ b/t/t7508-status.sh
@@ -579,7 +579,7 @@ cat >expect <<EOF
 #
 #	modified:   dir1/modified
 #
-# Modified submodules:
+# Submodule changes to be committed:
 #
 # * sm 0000000...$head (1):
 #   > Add foo
@@ -672,7 +672,7 @@ cat >expect <<EOF
 #
 #	modified:   dir1/modified
 #
-# Modified submodules:
+# Submodule changes to be committed:
 #
 # * sm 0000000...$head (1):
 #   > Add foo