1 files changed, 52 insertions, 0 deletions
diff --git a/t/t6500-gc.sh b/t/t6500-gc.sh
index 1762dfa6a3..41b0be575d 100755
--- a/t/t6500-gc.sh
+++ b/t/t6500-gc.sh
@@ -67,5 +67,57 @@ test_expect_success 'auto gc with too many loose objects does not attempt to cre
 	test_line_count = 2 new # There is one new pack and its .idx
 '
 
+run_and_wait_for_auto_gc () {
+	# We read stdout from gc for the side effect of waiting until the
+	# background gc process exits, closing its fd 9.  Furthermore, the
+	# variable assignment from a command substitution preserves the
+	# exit status of the main gc process.
+	# Note: this fd trickery doesn't work on Windows, but there is no
+	# need to, because on Win the auto gc always runs in the foreground.
+	doesnt_matter=$(git gc --auto 9>&1)
+}
+
+test_expect_success 'background auto gc does not run if gc.log is present and recent but does if it is old' '
+	test_commit foo &&
+	test_commit bar &&
+	git repack &&
+	test_config gc.autopacklimit 1 &&
+	test_config gc.autodetach true &&
+	echo fleem >.git/gc.log &&
+	test_must_fail git gc --auto 2>err &&
+	test_i18ngrep "^error:" err &&
+	test_config gc.logexpiry 5.days &&
+	test-chmtime =-345600 .git/gc.log &&
+	test_must_fail git gc --auto &&
+	test_config gc.logexpiry 2.days &&
+	run_and_wait_for_auto_gc &&
+	ls .git/objects/pack/pack-*.pack >packs &&
+	test_line_count = 1 packs
+'
+
+test_expect_success 'background auto gc respects lock for all operations' '
+	# make sure we run a background auto-gc
+	test_commit make-pack &&
+	git repack &&
+	test_config gc.autopacklimit 1 &&
+	test_config gc.autodetach true &&
+
+	# create a ref whose loose presence we can use to detect a pack-refs run
+	git update-ref refs/heads/should-be-loose HEAD &&
+	test_path_is_file .git/refs/heads/should-be-loose &&
+
+	# now fake a concurrent gc that holds the lock; we can use our
+	# shell pid so that it looks valid.
+	hostname=$(hostname || echo unknown) &&
+	printf "$$ %s" "$hostname" >.git/gc.pid &&
+
+	# our gc should exit zero without doing anything
+	run_and_wait_for_auto_gc &&
+	test_path_is_file .git/refs/heads/should-be-loose
+'
+
+# DO NOT leave a detached auto gc process running near the end of the
+# test script: it can run long enough in the background to racily
+# interfere with the cleanup in 'test_done'.
 
 test_done