Log keyring tracebacks

changelog/890.bugfix.rst

@@ -0,0 +1 @@
+Improve logging when keyring fails.

tests/test_auth.py

@@ -1,5 +1,6 @@
 import getpass
 import logging
+import re
 
 import pytest
 
@@ -152,14 +153,42 @@ def test_get_username_runtime_error_suppressed(
     entered_username, keyring_no_backends_get_credential, caplog, config
 ):
     assert auth.Resolver(config, auth.CredentialInput()).username == "entered user"
-    assert caplog.messages == ["fail!"]
+    assert re.search(
+        r"Error from keyring.+Traceback.+RuntimeError: fail!", caplog.text, re.DOTALL
+    )
 
 
 def test_get_password_runtime_error_suppressed(
     entered_password, keyring_no_backends, caplog, config
 ):
     assert auth.Resolver(config, auth.CredentialInput("user")).password == "entered pw"
-    assert caplog.messages == ["fail!"]
+    assert re.search(
+        r"Error from keyring.+Traceback.+RuntimeError: fail!", caplog.text, re.DOTALL
+    )
+
+
+@pytest.mark.parametrize(
+    "get_credential",
+    [
+        auth.Resolver.get_username_from_keyring,
+        auth.Resolver.get_password_from_keyring,
+    ],
+)
+def test_log_exception_on_keyring_failure(get_credential, config, monkeypatch, caplog):
+    class FailKeyring:
+        @staticmethod
+        def get_credential(system, username):
+            # Simulate the error from https://github.com/pypa/twine/issues/889
+            environ = {}
+            environ["HOME"]
+
+    monkeypatch.setattr(auth, "keyring", FailKeyring())
+
+    assert not get_credential(auth.Resolver(config, auth.CredentialInput()))
+
+    assert re.search(
+        r"Error from keyring.+Traceback.+KeyError: 'HOME'", caplog.text, re.DOTALL
+    )
 
 
 def test_get_username_return_none(entered_username, monkeypatch, config):

twine/auth.py

@@ -63,7 +63,7 @@ def get_username_from_keyring(self) -> Optional[str]:
             # To support keyring prior to 15.2
             pass
         except Exception as exc:
-            logger.warning(str(exc))
+            logger.warning("Error from keyring", exc_info=exc)
         return None
 
     def get_password_from_keyring(self) -> Optional[str]:
@@ -73,7 +73,7 @@ def get_password_from_keyring(self) -> Optional[str]:
             logger.info("Querying keyring for password")
             return cast(str, keyring.get_password(system, username))
         except Exception as exc:
-            logger.warning(str(exc))
+            logger.warning("Error from keyring", exc_info=exc)
         return None
 
     def username_from_keyring_or_prompt(self) -> str: