Emit warning if the documentation cannot be found for a given project.

Author: domdfcoding

seed_intersphinx_mapping/core.py

@@ -30,6 +30,7 @@
 import functools
 import json
 import re
+import warnings
 from typing import Any, Dict, Optional, Pattern, Tuple, Union
 
 # 3rd party
@@ -141,12 +142,12 @@ def seed_intersphinx_mapping(base_dir: PathLike) -> Dict[str, Tuple[str, Optiona
 		try:
 			doc_url = get_sphinx_doc_url(project_name)
 			intersphinx_mapping[project_name] = (doc_url, None)
-		except ValueError:
+		except (ValueError, requests.exceptions.ConnectionError):
 			# Couldn't get it from PyPI, trying fallback mapping
 			if project_name in fallback_mapping():
 				doc_url = fallback_mapping()[project_name]
 				intersphinx_mapping[project_name] = (doc_url, None)
-			# TODO: perhaps emit warning?
-			# TODO: handle user being offline
+			else:
+				warnings.warn(f"Unable to determine documentation url for project {project_name}")
 
 	return intersphinx_mapping

tests/test_seeding.py

@@ -26,4 +26,7 @@
 		)
 def test_seed_intersphinx_mapping(tmpdir, contents, expects):
 	(PathPlus(tmpdir) / "requirements.txt").write_text(contents)
-	assert seed_intersphinx_mapping(tmpdir) == expects
+
+	with pytest.warns(UserWarning) as w:
+		assert seed_intersphinx_mapping(tmpdir) == expects
+	assert len(w) == 1