Make test_all.py return nonzero when there are no fuzzers. (#4796)

Make test_all.py return nonzero when there are no fuzzers.

This matches the previous behavior.
Fixes https://github.com/google/oss-fuzz/issues/4795

2 files changed, 44 insertions, 0 deletions

diff --git a/infra/base-images/base-runner/test_all.py b/infra/base-images/base-runner/test_all.py
index 1524483df..dfa38260f 100755
--- a/infra/base-images/base-runner/test_all.py
+++ b/infra/base-images/base-runner/test_all.py
@@ -152,6 +152,10 @@ def test_all(out, fuzzing_language, allowed_broken_targets_percentage):
   """Do bad_build_check on all fuzz targets."""
   # TODO(metzman): Refactor so that we can convert test_one to python.
   fuzz_targets = find_fuzz_targets(out, fuzzing_language)
+  if not fuzz_targets:
+    print('ERROR: No fuzz targets found.')
+    return False
+
   pool = multiprocessing.Pool()
   bad_build_results = pool.map(do_bad_build_check, fuzz_targets)
   broken_targets = get_broken_fuzz_targets(bad_build_results, fuzz_targets)
diff --git a/infra/base-images/base-runner/test_test_all.py b/infra/base-images/base-runner/test_test_all.py
new file mode 100644
index 000000000..3771ec231
--- /dev/null
+++ b/infra/base-images/base-runner/test_test_all.py
@@ -0,0 +1,40 @@
+# Copyright 2020 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+"""Tests test_all.py"""
+import unittest
+from unittest import mock
+
+import test_all
+
+
+class TestTestAll(unittest.TestCase):
+  """Tests for the test_all_function."""
+
+  @mock.patch('test_all.find_fuzz_targets', return_value=[])
+  @mock.patch('builtins.print')
+  def test_test_all_no_fuzz_targets(self, mocked_print, _):
+    """Tests that test_all returns False when there are no fuzz targets."""
+    outdir = '/out'
+    fuzzing_language = 'c++'
+    allowed_broken_targets_percentage = 0
+    self.assertFalse(
+        test_all.test_all(outdir, fuzzing_language,
+                          allowed_broken_targets_percentage))
+    mocked_print.assert_called_with('ERROR: No fuzz targets found.')
+
+
+if __name__ == '__main__':
+  unittest.main()