[lit][unit] makes sure to print stderr when no test failures are found

In some situations, like running tests with sanitizers, all test passes
but the shard could still fail due to memory issues.

diff --git a/llvm/utils/lit/lit/formats/googletest.py b/llvm/utils/lit/lit/formats/googletest.py
index 5feefaa..6878ebc 100644 (file)
--- a/llvm/utils/lit/lit/formats/googletest.py
+++ b/llvm/utils/lit/lit/formats/googletest.py
@@ -163,6 +163,8 @@ class GoogleTest(TestFormat):
                     res.append(l)
             assert False, f'gtest did not report the result for ' + test_name
 
+        found_failed_test = False
+
         with open(test.gtest_json_file, encoding='utf-8') as f:
             jf = json.load(f)
 
@@ -179,6 +181,7 @@ class GoogleTest(TestFormat):
                     header = f"Script:\n--\n%s --gtest_filter=%s\n--\n" % (
                         ' '.join(cmd), testname)
                     if 'failures' in testinfo:
+                        found_failed_test = True
                         output += header
                         test_out = get_test_stdout(testname)
                         if test_out:
@@ -189,6 +192,12 @@ class GoogleTest(TestFormat):
                     elif result != 'COMPLETED':
                         output += header
                         output += 'unresolved test result\n'
+
+        # In some situations, like running tests with sanitizers, all test passes but
+        # the shard could still fail due to memory issues.
+        if not found_failed_test:
+            output += f"\n{out}\n--\nexit: {exitCode}\n--\n"
+
         return lit.Test.FAIL, output
 
     def prepareCmd(self, cmd):