test: add strict coverage for types

Author: G-Rath

.github/workflows/python-app.yml

@@ -48,3 +48,4 @@ jobs:
     - name: Check types
       run: |
         mypy .
+        mypy --strict tests/types.py

tests/types.py

@@ -0,0 +1,7 @@
+from markdownify import markdownify, LSTRIP, RSTRIP, STRIP
+
+markdownify("<p>Hello</p>") == "Hello"  # test default of STRIP
+markdownify("<p>Hello</p>", strip_document=LSTRIP) == "Hello\n\n"
+markdownify("<p>Hello</p>", strip_document=RSTRIP) == "\n\nHello"
+markdownify("<p>Hello</p>", strip_document=STRIP) == "Hello"
+markdownify("<p>Hello</p>", strip_document=None) == "\n\nHello\n\n"