[PATCH v2 4/6] fsmonitor: add test cases for fsmonitor extension

[Ben Peart <peartben@gmail.com>]

Add test cases that ensure status results are correct when using the new
fsmonitor extension.  Test untracked, modified, and new files by
ensuring the results are identical to when not using the extension.

Add a test to ensure updates to the index properly mark corresponding
entries in the index extension as dirty so that the status is correct
after commands that modify the index but don't trigger changes in the
working directory.

Add a test that verifies that if the fsmonitor extension doesn't tell
git about a change, it doesn't discover it on its own.  This ensures
git is honoring the extension and that we get the performance benefits
desired.

All test hooks output a marker file that is used to ensure the hook
was actually used to generate the test results.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
---
 t/t7519-status-fsmonitor.sh | 153 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)
 create mode 100755 t/t7519-status-fsmonitor.sh

diff --git a/t/t7519-status-fsmonitor.sh b/t/t7519-status-fsmonitor.sh
new file mode 100755
index 0000000000..d3cffc758f
--- /dev/null
+++ b/t/t7519-status-fsmonitor.sh
@@ -0,0 +1,153 @@
+#!/bin/sh
+
+test_description='git status with file system watcher'
+
+. ./test-lib.sh
+
+clean_repo () {
+	git reset --hard HEAD
+	git clean -fd
+	rm marker -f
+}
+
+dirty_repo () {
+	: >untracked
+	: >dir1/untracked
+	: >dir2/untracked
+	echo 1 >modified
+	echo 2 >dir1/modified
+	echo 3 >dir2/modified
+	echo 4 >new
+	echo 5 >dir1/new
+	echo 6 >dir2/new
+	git add new
+	git add dir1/new
+	git add dir2/new
+}
+
+# The test query-fsmonitor hook proc will output a marker file we can use to
+# ensure the hook was actually used to generate the correct results.
+
+test_expect_success 'setup' '
+	mkdir -p .git/hooks &&
+	write_script .git/hooks/query-fsmonitor<<-\EOF &&
+	: >marker
+	printf "untracked\0"
+	printf "dir1/untracked\0"
+	printf "dir2/untracked\0"
+	printf "modified\0"
+	printf "dir1/modified\0"
+	printf "dir2/modified\0"
+	printf "new\0""
+	printf "dir1/new\0"
+	printf "dir2/new\0"
+	EOF
+	: >tracked &&
+	: >modified &&
+	mkdir dir1 &&
+	: >dir1/tracked &&
+	: >dir1/modified &&
+	mkdir dir2 &&
+	: >dir2/tracked &&
+	: >dir2/modified &&
+	git add . &&
+	test_tick &&
+	git commit -m initial &&
+	dirty_repo
+'
+
+cat >.gitignore <<\EOF
+.gitignore
+expect*
+output*
+marker*
+EOF
+
+# Status is well tested elsewhere so we'll just ensure that the results are
+# the same when using core.fsmonitor. First call after turning on the option
+# does a complete scan so need to do two calls to ensure we test the new
+# codepath.
+
+test_expect_success 'status with core.untrackedcache true' '
+	git config core.fsmonitor true  &&
+	git config core.untrackedcache true &&
+	git -c core.fsmonitor=false -c core.untrackedcache=true status >expect &&
+	clean_repo &&
+	git status &&
+	test_path_is_missing marker &&
+	dirty_repo &&
+	git status >output &&
+	test_path_is_file marker &&
+	test_i18ncmp expect output
+'
+
+
+test_expect_success 'status with core.untrackedcache false' '
+	git config core.fsmonitor true &&
+	git config core.untrackedcache false &&
+	git -c core.fsmonitor=false -c core.untrackedcache=false status >expect &&
+	clean_repo &&
+	git status &&
+	test_path_is_missing marker &&
+	dirty_repo &&
+	git status >output &&
+	test_path_is_file marker &&
+	test_i18ncmp expect output
+'
+
+# Ensure commands that call refresh_index() to move the index back in time
+# properly invalidate the fsmonitor cache
+
+test_expect_success 'refresh_index() invalidates fsmonitor cache' '
+	git config core.fsmonitor true &&
+	git config core.untrackedcache true &&
+	clean_repo &&
+	git status &&
+	test_path_is_missing marker &&
+	dirty_repo &&
+	write_script .git/hooks/query-fsmonitor<<-\EOF &&
+	:>marker
+	EOF
+	git add . &&
+	git commit -m "to reset" &&
+	git status &&
+	test_path_is_file marker &&
+	git reset HEAD~1 &&
+	git status >output &&
+	test_path_is_file marker &&
+	git -c core.fsmonitor=false status >expect &&
+	test_i18ncmp expect output
+'
+
+# Now make sure it's actually skipping the check for modified and untracked
+# files unless it is told about them.  Note, after "git reset --hard HEAD" no
+# extensions exist other than 'TREE' so do a "git status" to get the extension
+# written before testing the results.
+
+test_expect_success 'status doesnt detect unreported modifications' '
+	git config core.fsmonitor true &&
+	git config core.untrackedcache true &&
+	write_script .git/hooks/query-fsmonitor<<-\EOF &&
+	:>marker
+	EOF
+	clean_repo &&
+	git status &&
+	test_path_is_missing marker &&
+	: >untracked &&
+	echo 2 >dir1/modified &&
+	git status >output &&
+	test_path_is_file marker &&
+	test_i18ngrep ! "Changes not staged for commit:" output &&
+	test_i18ngrep ! "Untracked files:" output &&
+	write_script .git/hooks/query-fsmonitor<<-\EOF &&
+	:>marker
+	printf "untracked%s\0"
+	printf "dir1/modified\0"
+	EOF
+	git status >output &&
+	test_path_is_file marker &&
+	test_i18ngrep "Changes not staged for commit:" output &&
+	test_i18ngrep "Untracked files:" output
+'
+
+test_done
-- 
2.13.0.windows.1.6.g4597375fc3