test: Add backend error handling tests for Value class

- Add test_get_value_backend_error to verify RuntimeError propagation
- Add test_set_value_backend_error to verify RuntimeError propagation
- Fix type validation in Value.set method

Author: ritwik-g

helm_values_manager/models/value.py

@@ -57,10 +57,10 @@ def set(self, value: Union[str, int, float, bool, None]) -> None:
         Set the value using the backend.
 
         Args:
-            value: The value to store, can be a raw value, a secret reference, or None
+            value: The value to store, can be a string, number, boolean, or None
 
         Raises:
-            ValueError: If value is not a string, number, boolean, or None
+            ValueError: If the value is not a string, number, boolean, or None
             RuntimeError: If backend operation fails
         """
         if not isinstance(value, (str, int, float, bool, type(None))):
@@ -71,6 +71,7 @@ def set(self, value: Union[str, int, float, bool, None]) -> None:
             HelmLogger.debug("Successfully set value for path %s", self.path)
         except Exception as e:
             HelmLogger.error("Failed to set value for path %s in environment %s: %s", self.path, self.environment, e)
+            HelmLogger.error("Error setting value: %s", e)
             raise
 
     def to_dict(self) -> Dict[str, Any]:

tests/unit/models/test_value.py

@@ -81,6 +81,28 @@ def test_set_invalid_type(mock_backend):
         value.set({"key": "value"})  # Dictionary is not a valid type
 
 
+def test_get_value_backend_error(mock_backend):
+    """Test error handling when backend.get_value raises an exception."""
+    mock_backend.get_value.side_effect = RuntimeError("Backend error")
+    value = Value(path="app.replicas", environment="dev", _backend=mock_backend)
+
+    with pytest.raises(RuntimeError, match="Backend error"):
+        value.get()
+
+    mock_backend.get_value.assert_called_once_with("app.replicas", "dev", False)
+
+
+def test_set_value_backend_error(mock_backend):
+    """Test error handling when backend.set_value raises an exception."""
+    mock_backend.set_value.side_effect = RuntimeError("Backend error")
+    value = Value(path="app.replicas", environment="dev", _backend=mock_backend)
+
+    with pytest.raises(RuntimeError, match="Backend error"):
+        value.set("test-value")
+
+    mock_backend.set_value.assert_called_once_with("app.replicas", "dev", "test-value")
+
+
 def test_to_dict(mock_backend):
     """Test serializing a value."""
     value = Value(path="app.replicas", environment="dev", _backend=mock_backend)