Merge pull request #3153 from brianmaissy/document_not_to_call_main_m…

…ultiple_times Added note that calling pytest.main multiple times from the same process is not recommended because of import caching
pytest-dev · Jan 26, 2018 · 3bc7ced · 3bc7ced
2 parents ff90c9e + 4285325
commit 3bc7ced
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 1 deletion.
diff --git a/changelog/3143.doc b/changelog/3143.doc
@@ -0,0 +1 @@
+Added note that calling pytest.main multiple times from the same process is not recommended because of import caching.
diff --git a/doc/en/usage.rst b/doc/en/usage.rst
@@ -387,6 +387,15 @@ hook was invoked::
 
     $ python myinvoke.py
     *** test run reporting finishing
-    
+
+.. note::
+
+    Calling ``pytest.main()`` will result in importing your tests and any modules
+    that they import. Due to the caching mechanism of python's import system,
+    making subsequent calls to ``pytest.main()`` from the same process will not
+    reflect changes to those files between the calls. For this reason, making
+    multiple calls to ``pytest.main()`` from the same process (in order to re-run
+    tests, for example) is not recommended.
+
 
 .. include:: links.inc