Merge branch 'en/stash-apply-sparse-checkout' into maint

"git stash" did not work well in a sparsely checked out working
tree.

* en/stash-apply-sparse-checkout:
  stash: fix stash application in sparse-checkouts
  stash: remove unnecessary process forking
  t7012: add a testcase demonstrating stash apply bugs in sparse checkouts

2 files changed, 96 insertions, 8 deletions

diff --git a/t/lib-submodule-update.sh b/t/lib-submodule-update.sh
index bd3fa3c6da..4b714e9308 100644
--- a/t/lib-submodule-update.sh
+++ b/t/lib-submodule-update.sh
@@ -316,14 +316,7 @@ test_submodule_switch_common () {
 	command="$1"
 	######################### Appearing submodule #########################
 	# Switching to a commit letting a submodule appear creates empty dir ...
-	if test "$KNOWN_FAILURE_STASH_DOES_IGNORE_SUBMODULE_CHANGES" = 1
-	then
-		# Restoring stash fails to restore submodule index entry
-		RESULT="failure"
-	else
-		RESULT="success"
-	fi
-	test_expect_$RESULT "$command: added submodule creates empty directory" '
+	test_expect_success "$command: added submodule creates empty directory" '
 		prolog &&
 		reset_work_tree_to no_submodule &&
 		(
@@ -337,6 +330,13 @@ test_submodule_switch_common () {
 		)
 	'
 	# ... and doesn't care if it already exists.
+	if test "$KNOWN_FAILURE_STASH_DOES_IGNORE_SUBMODULE_CHANGES" = 1
+	then
+		# Restoring stash fails to restore submodule index entry
+		RESULT="failure"
+	else
+		RESULT="success"
+	fi
 	test_expect_$RESULT "$command: added submodule leaves existing empty directory alone" '
 		prolog &&
 		reset_work_tree_to no_submodule &&
diff --git a/t/t7012-skip-worktree-writing.sh b/t/t7012-skip-worktree-writing.sh
index 7476781979..e5c6a038fb 100755
--- a/t/t7012-skip-worktree-writing.sh
+++ b/t/t7012-skip-worktree-writing.sh
@@ -149,6 +149,94 @@ test_expect_success '--ignore-skip-worktree-entries leaves worktree alone' '
 		--diff-filter=D -- keep-me.t
 '
 
+test_expect_success 'stash restore in sparse checkout' '
+	test_create_repo stash-restore &&
+	(
+		cd stash-restore &&
+
+		mkdir subdir &&
+		echo A >subdir/A &&
+		echo untouched >untouched &&
+		echo removeme >removeme &&
+		echo modified >modified &&
+		git add . &&
+		git commit -m Initial &&
+
+		echo AA >>subdir/A &&
+		echo addme >addme &&
+		echo tweaked >>modified &&
+		rm removeme &&
+		git add addme &&
+
+		git stash push &&
+
+		git sparse-checkout set subdir &&
+
+		# Ensure after sparse-checkout we only have expected files
+		cat >expect <<-EOF &&
+		S modified
+		S removeme
+		H subdir/A
+		S untouched
+		EOF
+		git ls-files -t >actual &&
+		test_cmp expect actual &&
+
+		test_path_is_missing addme &&
+		test_path_is_missing modified &&
+		test_path_is_missing removeme &&
+		test_path_is_file    subdir/A &&
+		test_path_is_missing untouched &&
+
+		# Put a file in the working directory in the way
+		echo in the way >modified &&
+		git stash apply &&
+
+		# Ensure stash vivifies modifies paths...
+		cat >expect <<-EOF &&
+		H addme
+		H modified
+		H removeme
+		H subdir/A
+		S untouched
+		EOF
+		git ls-files -t >actual &&
+		test_cmp expect actual &&
+
+		# ...and that the paths show up in status as changed...
+		cat >expect <<-EOF &&
+		A  addme
+		 M modified
+		 D removeme
+		 M subdir/A
+		?? actual
+		?? expect
+		?? modified.stash.XXXXXX
+		EOF
+		git status --porcelain | \
+			sed -e s/stash......./stash.XXXXXX/ >actual &&
+		test_cmp expect actual &&
+
+		# ...and that working directory reflects the files correctly
+		test_path_is_file    addme &&
+		test_path_is_file    modified &&
+		test_path_is_missing removeme &&
+		test_path_is_file    subdir/A &&
+		test_path_is_missing untouched &&
+
+		# ...including that we have the expected "modified" file...
+		cat >expect <<-EOF &&
+		modified
+		tweaked
+		EOF
+		test_cmp expect modified &&
+
+		# ...and that the other "modified" file is still present...
+		echo in the way >expect &&
+		test_cmp expect modified.stash.*
+	)
+'
+
 #TODO test_expect_failure 'git-apply adds file' false
 #TODO test_expect_failure 'git-apply updates file' false
 #TODO test_expect_failure 'git-apply removes file' false