Improve error filtering for anyOf and oneOf

- Do not filter object level validations (e.g. required) in anyOf/oneOf.
- Filter anyOf/oneOf/additionalProperties errors
- Extend core tests

packages/core/src/reducers/core.ts

@@ -340,20 +340,47 @@ export const errorsAt = (
   schema: JsonSchema,
   matchPath: (path: string) => boolean
 ) => (errors: ErrorObject[]): ErrorObject[] => {
+  // Get data paths of oneOf and anyOf errors to later determine whether an error occurred inside a subschema of oneOf or anyOf.
   const combinatorPaths = filter(
     errors,
     error => error.keyword === 'oneOf' || error.keyword === 'anyOf'
   ).map(error => error.dataPath);
 
   return filter(errors, error => {
+    // Filter errors that match any keyword that we don't want to show in the UI
+    if (filteredErrorKeywords.indexOf(error.keyword) !== -1) {
+      return false;
+    }
+
     let result = matchPath(error.dataPath);
-    if (combinatorPaths.findIndex(p => instancePath.startsWith(p)) !== -1) {
-      result = result && isEqual(error.parentSchema, schema);
+    // In anyOf and oneOf blocks with "primitive subschemas" (not defining an object),
+    // we want to make sure that errors are only shown for the correct subschema.
+    // Therefore, we compare the error's parent schema with the property's schema.
+    // This is necessary because in the primitive case the error's data path is the same for all subschemas:
+    // It directly points to the property defining the anyOf/oneOf.
+    // In contrast, this comparison must not be done for errors whose parent schema defines an object
+    // because the parent schema can never match the property schema (e.g. for 'required' checks).
+    const parentSchema: JsonSchema | undefined = error.parentSchema;
+    if (result && parentSchema?.type !== 'object'
+      && combinatorPaths.findIndex(p => instancePath.startsWith(p)) !== -1) {
+      result = result && isEqual(parentSchema, schema);
     }
     return result;
   });
 };
 
+/**
+ * The error-type of an AJV error is defined by its `keyword` property.
+ * Certain errors are filtered because they don't fit to any rendered control.
+ * All of them have in common that we don't want to show them in the UI
+ * because controls will show the actual reason why they don't match their correponding sub schema.
+ * - additionalProperties: Indicates that a property is present that is not defined in the schema.
+ *      Jsonforms only allows to edit defined properties. These errors occur if an oneOf doesn't match.
+ * - anyOf: Indicates that an anyOf definition itself is not valid because none of its subschemas matches.
+ * - oneOf: Indicates that an oneOf definition itself is not valid because not exactly one of its subschemas matches.
+ */
+const filteredErrorKeywords = ['additionalProperties', 'anyOf', 'oneOf'];
+
 const getErrorsAt = (
   instancePath: string,
   schema: JsonSchema,

packages/core/test/reducers/core.test.ts

@@ -754,6 +754,110 @@ test('errorAt filters required', t => {
   t.deepEqual(filtered[0], state.errors[1]);
 });
 
+test('errorAt filters required in oneOf object', t => {
+  const ajv = createAjv();
+  const schema: JsonSchema = {
+    type: 'object',
+    properties: {
+      fooOrBar: {
+        oneOf: [
+          {
+            title: 'Foo',
+            type: 'object',
+            properties: {
+              foo: {
+                type: 'string'
+              }
+            },
+            required: ['foo'],
+            additionalProperties: false
+          },
+          {
+            title: 'Bar',
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'number'
+              }
+            },
+            required: ['bar'],
+            additionalProperties: false
+          }
+        ]
+      }
+    },
+    additionalProperties: false
+  };
+  const data = { fooOrBar: { } };
+  const v = ajv.compile(schema);
+  const errors = sanitizeErrors(v, data);
+
+  const state: JsonFormsCore = {
+    data,
+    schema,
+    uischema: undefined,
+    errors
+  };
+  const filtered = errorAt(
+    'fooOrBar.foo',
+    schema.properties.fooOrBar.oneOf[0].properties.foo
+  )(state);
+  t.is(filtered.length, 1);
+  t.deepEqual(filtered[0].keyword, 'required');
+});
+
+test('errorAt filters required in anyOf object', t => {
+  const ajv = createAjv();
+  const schema: JsonSchema = {
+    type: 'object',
+    properties: {
+      fooOrBar: {
+        anyOf: [
+          {
+            title: 'Foo',
+            type: 'object',
+            properties: {
+              foo: {
+                type: 'string'
+              }
+            },
+            required: ['foo'],
+            additionalProperties: false
+          },
+          {
+            title: 'Bar',
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'number'
+              }
+            },
+            required: ['bar'],
+            additionalProperties: false
+          }
+        ]
+      }
+    },
+    additionalProperties: false
+  };
+  const data = { fooOrBar: { } };
+  const v = ajv.compile(schema);
+  const errors = sanitizeErrors(v, data);
+
+  const state: JsonFormsCore = {
+    data,
+    schema,
+    uischema: undefined,
+    errors
+  };
+  const filtered = errorAt(
+    'fooOrBar.foo',
+    schema.properties.fooOrBar.anyOf[0].properties.foo
+  )(state);
+  t.is(filtered.length, 1);
+  t.deepEqual(filtered[0].keyword, 'required');
+});
+
 test('errorAt filters array minItems', t => {
   const ajv = createAjv();
   const schema: JsonSchema = {
@@ -973,6 +1077,7 @@ test('errorAt filters oneOf objects', t => {
     schema.properties.coloursOrNumbers.oneOf[1].properties.colour
   )(state);
   t.is(filtered.length, 1);
+  t.is(filtered[0].keyword, 'enum');
   t.deepEqual(filtered[0], state.errors[1]);
 });
 

packages/examples/src/oneOf.ts

@@ -35,15 +35,17 @@ export const schema = {
         city: { type: 'string' },
         state: { type: 'string' }
       },
-      required: ['street_address', 'city', 'state']
+      required: ['street_address', 'city', 'state'],
+      additionalProperties: false
     },
     user: {
       type: 'object',
       properties: {
         name: { type: 'string' },
         mail: { type: 'string' }
       },
-      required: ['name', 'mail']
+      required: ['name', 'mail'],
+      additionalProperties: false
     }
   },
 
@@ -54,7 +56,8 @@ export const schema = {
     addressOrUser: {
       oneOf: [{ $ref: '#/definitions/address' }, { $ref: '#/definitions/user' }]
     }
-  }
+  },
+  required: ['name']
 };
 
 export const uischema = {