Return None when loading a null !path

Author: Aegdesil

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 ## Unreleased
+## 4.0.1
+### Fixes
+- Loading a null `!path` will now return `None` instead of raising an Exception
+
 ## 4.0.0
 ### Breaking changes
 - The `!env` tag has been removed, environment variables can now be loaded anywhere

CONTRIBUTING.md

@@ -21,6 +21,7 @@ Run `python -m unitttest discover` to run the tests.
 
 Run these commands to check the files linting:
 ```shell script
-pylint --load-plugins pylint_quotes configue
-pylint --load-plugins pylint_quotes tests --disable=protected-access,too-many-instance-attributes,no-self-use
+black . --check -l 120
+pylint configue
+pylint tests --disable=too-many-instance-attributes,no-self-use,similarities
 ```

configue/file_loader.py

@@ -1,6 +1,6 @@
 import logging
 import os
-from typing import Any, List, TYPE_CHECKING, Type, Union, cast
+from typing import Any, List, Optional, TYPE_CHECKING, Type, Union, cast
 
 from yaml import Loader, MappingNode, Node, ScalarNode, SequenceNode
 
@@ -71,8 +71,11 @@ def _load_import(self, loader: ConfigueLoader, tag_suffix: str, node: ScalarNode
         path = self._load_path(loader, node)
         return self._root_loader.load_file(path, tag_suffix[1:])
 
-    def _load_path(self, loader: ConfigueLoader, node: ScalarNode) -> str:
-        path = os.path.expanduser(loader.construct_scalar(node))
+    def _load_path(self, loader: ConfigueLoader, node: ScalarNode) -> Optional[str]:
+        raw_path = loader.construct_scalar(node)
+        if raw_path is None:
+            return None
+        path = os.path.expanduser(raw_path)
         return os.path.join(os.path.dirname(self._file_path), path)
 
     def _load_cfg(self, loader: ConfigueLoader, node: ScalarNode) -> Any:

tests/test_configue.py

@@ -116,6 +116,12 @@ def test_load_external_value(self):
         result = configue.load(self._get_path("test_file_2.yml"), "const")
         self.assertEqual(CONSTANT, result)
 
+    def test_null_path(self):
+        result = configue.load(self._get_path("test_file_2.yml"), "paths")
+        self.assertIsNone(result["path"])
+        self.assertEqual(os.path.expanduser("~"), result["path2"])
+        self.assertIsNone(result["path3"])
+
     @staticmethod
     def _get_path(file_name: str) -> str:
         return os.path.join(os.path.dirname(__file__), file_name)

tests/test_file_2.yml

@@ -8,3 +8,7 @@ invalid_class:
   (): tests.external_module.CONSTANT
 
 const: !ext tests.external_module.CONSTANT
+paths:
+  path: !path ${ENV_PATH-null}
+  path2: !path "${ENV_PATH-~}"
+  path3: !path ${ENV_PATH-~}