add test for child errors

test/test_build.py

@@ -117,7 +117,20 @@ def test_load_requires(self):
         text = 'test'
         output = gokart.build(_LoadRequires(task=_DummyTask(param=text)), reset_register=False)
         self.assertEqual(output, text)
-
+
+    def test_build_with_child_task_error(self):
+        class CheckException(Exception):
+            pass
+        class FailTask(gokart.TaskOnKart):
+            def run(self):
+                raise CheckException()
+
+        try:
+            t = FailTask()
+            gokart.build(t, reset_register=False, log_level=logging.CRITICAL)
+        except GokartBuildError as e:
+            self.assertEqual(len(e.raised_exceptions), 1)
+            self.assertIsInstance(e.raised_exceptions[t.make_unique_id()][0], CheckException)
 
 class LoggerConfigTest(unittest.TestCase):
     def test_logger_config(self):