[PATCH v4 2/6] unit-tests: show location of checks outside of tests

["René Scharfe" <l.s.r@web.de>]

Checks outside of tests are caught at runtime and reported like this:

 Assertion failed: (ctx.running), function test_assert, file test-lib.c, line 267.

The assert() call aborts the unit test and doesn't reveal the location
or even the type of the offending check, as test_assert() is called by
all of them.

Handle it like the opposite case, a test without any checks: Don't
abort, but report the location of the actual check, along with a message
explaining the situation.  The output for example above becomes:

 # BUG: check outside of test at t/helper/test-example-tap.c:75

... and the unit test program continues and indicates the error in its
exit code at the end.

Signed-off-by: René Scharfe <l.s.r@web.de>
---
 t/helper/test-example-tap.c | 2 ++
 t/t0080-unit-test-output.sh | 5 +++--
 t/unit-tests/test-lib.c     | 7 ++++++-
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/t/helper/test-example-tap.c b/t/helper/test-example-tap.c
index d072ad559f..79c12b01cd 100644
--- a/t/helper/test-example-tap.c
+++ b/t/helper/test-example-tap.c
@@ -72,6 +72,8 @@ static void t_empty(void)

 int cmd__example_tap(int argc, const char **argv)
 {
+	check(1);
+
 	test_res = TEST(check_res = check_int(1, ==, 1), "passing test");
 	TEST(t_res(1), "passing test and assertion return 1");
 	test_res = TEST(check_res = check_int(1, ==, 2), "failing test");
diff --git a/t/t0080-unit-test-output.sh b/t/t0080-unit-test-output.sh
index 9ec47b7360..fe221f3bdb 100755
--- a/t/t0080-unit-test-output.sh
+++ b/t/t0080-unit-test-output.sh
@@ -7,9 +7,10 @@ TEST_PASSES_SANITIZE_LEAK=true

 test_expect_success 'TAP output from unit tests' - <<\EOT
 	cat >expect <<-EOF &&
+	# BUG: check outside of test at t/helper/test-example-tap.c:75
 	ok 1 - passing test
 	ok 2 - passing test and assertion return 1
-	# check "1 == 2" failed at t/helper/test-example-tap.c:77
+	# check "1 == 2" failed at t/helper/test-example-tap.c:79
 	#    left: 1
 	#   right: 2
 	not ok 3 - failing test
@@ -46,7 +47,7 @@ test_expect_success 'TAP output from unit tests' - <<\EOT
 	#    left: '\\\\'
 	#   right: '\\''
 	not ok 17 - messages from failing string and char comparison
-	# BUG: test has no checks at t/helper/test-example-tap.c:92
+	# BUG: test has no checks at t/helper/test-example-tap.c:94
 	not ok 18 - test with no checks
 	ok 19 - test with no checks returns 0
 	1..19
diff --git a/t/unit-tests/test-lib.c b/t/unit-tests/test-lib.c
index 3c513ce59a..989dc758e6 100644
--- a/t/unit-tests/test-lib.c
+++ b/t/unit-tests/test-lib.c
@@ -264,7 +264,12 @@ static void test_todo(void)

 int test_assert(const char *location, const char *check, int ok)
 {
-	assert(ctx.running);
+	if (!ctx.running) {
+		test_msg("BUG: check outside of test at %s",
+			 make_relative(location));
+		ctx.failed = 1;
+		return 0;
+	}

 	if (ctx.result == RESULT_SKIP) {
 		test_msg("skipping check '%s' at %s", check,
--
2.46.0