tests: Add tests for python application factories

Add the following tests cases:

1. When "factory" key is used inside the "targets" option.
2. When "factory" key is used at the root level of python application
   config.
3. When factory returns invalid callable or When factory is invalid
   callable

Link: <https://github.com/nginx/unit/pull/1336>
[ Commit subject & message formatting tweaks - Andrew ]
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/test/python/factory/wsgi.py b/test/python/factory/wsgi.py
new file mode 100644
index 00000000..8ad4887b
--- /dev/null
+++ b/test/python/factory/wsgi.py
@@ -0,0 +1,23 @@
+def wsgi_a(env, start_response):
+    start_response("200", [("Content-Length", "1")])
+    return [b"1"]
+
+
+def wsgi_b(env, start_response):
+    start_response("200", [("Content-Length", "1")])
+    return [b"2"]
+
+
+def wsgi_a_factory():
+    return wsgi_a
+
+
+def wsgi_b_factory():
+    return wsgi_b
+
+
+wsgi_invalid_callable = None
+
+
+def wsgi_factory_returning_invalid_callable():
+    return wsgi_invalid_callable