Raise exception for missing config file

tests/conftest.py

@@ -4,11 +4,15 @@
 import pytest
 
 from twine import settings
+from twine import utils
 
 
 @pytest.fixture()
-def config_file(tmpdir):
-    return tmpdir / ".pypirc"
+def config_file(tmpdir, monkeypatch):
+    path = tmpdir / ".pypirc"
+    # Mimic common case of .pypirc in home directory
+    monkeypatch.setattr(utils, "DEFAULT_CONFIG_FILE", path)
+    return path
 
 
 @pytest.fixture

tests/test_utils.py

@@ -171,10 +171,24 @@ def test_get_repository_config_with_invalid_url(config_file, repo_url, message):
         utils.get_repository_from_config(config_file, "pypi", repo_url)
 
 
-def test_get_repository_config_missing_config(config_file):
-    """Raise an exception when a repository isn't defined in .pypirc."""
-    with pytest.raises(exceptions.InvalidConfiguration):
-        utils.get_repository_from_config(config_file, "foobar")
+def test_get_repository_config_missing_repository(write_config_file):
+    """Raise an exception when a custom repository isn't defined in .pypirc."""
+    config_file = write_config_file("")
+    with pytest.raises(
+        exceptions.InvalidConfiguration,
+        match="Missing 'missing-repository'",
+    ):
+        utils.get_repository_from_config(config_file, "missing-repository")
+
+
+@pytest.mark.parametrize("repository", ["pypi", "missing-repository"])
+def test_get_repository_config_missing_file(repository):
+    """Raise an exception when a custom config file doesn't exist."""
+    with pytest.raises(
+        exceptions.InvalidConfiguration,
+        match=r"No such file.*missing-file",
+    ):
+        utils.get_repository_from_config("missing-file", repository)
 
 
 def test_get_config_deprecated_pypirc():

twine/settings.py

@@ -52,7 +52,7 @@ def __init__(
         password: Optional[str] = None,
         non_interactive: bool = False,
         comment: Optional[str] = None,
-        config_file: str = "~/.pypirc",
+        config_file: str = utils.DEFAULT_CONFIG_FILE,
         skip_existing: bool = False,
         cacert: Optional[str] = None,
         client_cert: Optional[str] = None,
@@ -244,7 +244,7 @@ def register_argparse_arguments(parser: argparse.ArgumentParser) -> None:
         )
         parser.add_argument(
             "--config-file",
-            default="~/.pypirc",
+            default=utils.DEFAULT_CONFIG_FILE,
             help="The .pypirc config file to use.",
         )
         parser.add_argument(

twine/utils.py

@@ -33,6 +33,8 @@
 DEFAULT_REPOSITORY = "https://upload.pypi.org/legacy/"
 TEST_REPOSITORY = "https://test.pypi.org/legacy/"
 
+DEFAULT_CONFIG_FILE = "~/.pypirc"
+
 # TODO: In general, it seems to be assumed that the values retrieved from
 # instances of this type aren't None, except for username and password.
 # Type annotations would be cleaner if this were Dict[str, str], but that
@@ -48,13 +50,20 @@ def get_config(path: str) -> Dict[str, RepositoryConfig]:
 
     Format: https://packaging.python.org/specifications/pypirc/
 
-    If the file doesn't exist, return a default configuration for pypyi and testpypi.
+    If the default config file doesn't exist, return a default configuration for
+    pypyi and testpypi.
     """
+    realpath = os.path.realpath(os.path.expanduser(path))
     parser = configparser.RawConfigParser()
 
-    path = os.path.expanduser(path)
-    if parser.read(path):
-        logger.info(f"Using configuration from {path}")
+    try:
+        with open(realpath) as f:
+            parser.read_file(f)
+            logger.info(f"Using configuration from {realpath}")
+    except FileNotFoundError:
+        # User probably set --config-file, but the file can't be read
+        if path != DEFAULT_CONFIG_FILE:
+            raise
 
     # server-login is obsolete, but retained for backwards compatibility
     defaults: RepositoryConfig = {
@@ -121,8 +130,11 @@ def get_repository_from_config(
             "username": None,
             "password": None,
         }
+
     try:
         return get_config(config_file)[repository]
+    except OSError as exc:
+        raise exceptions.InvalidConfiguration(str(exc))
     except KeyError:
         raise exceptions.InvalidConfiguration(
             f"Missing '{repository}' section from {config_file}.\n"