Merge pull request #27 from larsmaxfield/developer/lars

Fix #26: Don't delete object if already empty

Author: larsmaxfield

jsonschema_fill_default/jsonschema_fill_default.py

@@ -114,6 +114,13 @@ def _fill_empty_property(schema: dict):
         return None
 
 
+def _is_empty_object(x):
+    """True if an empty object, False if not empty and/or not an object"""
+    if not isinstance(x, (list, tuple, dict, set, range)):
+        return False
+    return not x
+
+
 def _fill_properties(instance: dict, schema: dict):
     """Recursively fill a JSON instance with schema "properties" defaults
 
@@ -135,10 +142,12 @@ def _fill_properties(instance: dict, schema: dict):
         if any(key in ["properties", "oneOf", "allOf", "anyOf", "if", "dependentSchemas"] for key in subschema):  # Recursion
             if _property not in instance:
                 instance[_property] = dict()
+                _was_empty = False
+            else:
+                _was_empty = _is_empty_object(instance[_property])
             fill_default(instance[_property], subschema)
-            if isinstance(instance[_property], (list, tuple, dict, set)):
-                if len(instance[_property]) == 0:  # No default found inside
-                    del instance[_property]
+            if not _was_empty and _is_empty_object(instance[_property]):
+                del instance[_property]
         if _property not in instance \
                 and "default" in subschema:
             instance[_property] = subschema["default"]

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "jsonschema-fill-default"
-version = "0.1.2.20250130"
+version = "0.1.3.20250131"
 description = "Fill a JSON instance with the missing defaults from its JSON Schema Draft 2020-12-valid schema"
 authors = ["Lars Maxfield"]
 readme = "README.md"

tests/unit/test_validate_and_fill.py

@@ -703,6 +703,53 @@
                 }
             }
         ]
+    },
+    "emptyExisting": {
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "title": "JSON Schema of 'dependentSchemas' with nested keywords",
+            "type": "object",
+            "properties": {
+                "subObject": {
+                    "allOf": [
+                        {
+                            "if": {"required": ["exists"]},
+                            "then": {
+                                "properties": {
+                                    "string": {"default": "nested"}
+                                }
+                            }
+                        }
+                    ]
+                }
+            }
+        },
+        "instances": [
+            {  # Empty
+                "original": {
+                    "subObject": {}
+                },
+                "expected": {
+                    "subObject": {}
+                }
+            },
+            {  # Partial
+                "original": {
+                    "subObject": {"exists": True}
+                },
+                "expected": {
+                    "subObject": {"exists": True, "string": "nested"}
+                }
+            },
+            {  # Partial
+                "original": {
+                    "subObject": {"string": "hello"}
+                },
+                "expected": {
+                    "subObject": {"string": "hello"}
+                }
+            }
+        ]
     }
 }