fix: handle compatible enums

Author: P0lip

src/utils/__tests__/mergeAllOf.spec.ts

@@ -0,0 +1,76 @@
+import { JSONSchema4 } from 'json-schema';
+import { mergeAllOf } from '../mergeAllOf';
+
+describe('mergeAllOf util', () => {
+  describe('enums merging', () => {
+    test('given incompatible, should mark enum as empty', () => {
+      const schema: JSONSchema4 = {
+        allOf: [
+          {
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'string',
+                enum: ['jonas', 'frederik'],
+              },
+            },
+          },
+          {
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'string',
+                enum: ['john', 'chris'],
+              },
+            },
+          },
+        ],
+      };
+
+      expect(mergeAllOf(schema, [], jest.fn())).toEqual({
+        properties: {
+          bar: {
+            enum: [],
+            type: 'string',
+          },
+        },
+        type: 'object',
+      });
+    });
+
+    test('given incompatible, should merge normally', () => {
+      const schema: JSONSchema4 = {
+        allOf: [
+          {
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'string',
+                enum: ['jonas', 'frederik'],
+              },
+            },
+          },
+          {
+            type: 'object',
+            properties: {
+              bar: {
+                type: 'string',
+                enum: ['jonas', 'frederik'],
+              },
+            },
+          },
+        ],
+      };
+
+      expect(mergeAllOf(schema, [], jest.fn())).toEqual({
+        properties: {
+          bar: {
+            enum: ['jonas', 'frederik'],
+            type: 'string',
+          },
+        },
+        type: 'object',
+      });
+    });
+  });
+});

src/utils/mergeAllOf.ts

@@ -1,7 +1,7 @@
 import { pathToPointer } from '@stoplight/json';
 import { JsonPath } from '@stoplight/types';
 import { JSONSchema4 } from 'json-schema';
-import { cloneDeep } from 'lodash';
+import { cloneDeep, compact } from 'lodash';
 import { ResolvingError } from '../errors';
 import { WalkerRefResolver } from '../tree/utils/populateTree';
 
@@ -14,6 +14,9 @@ function _mergeAllOf(schema: JSONSchema4, path: JsonPath, resolveRef: WalkerRefR
       defaultResolver(values: any) {
         return Object.assign({}, ...values);
       },
+      enum(values: unknown[]) {
+        return resolveAllOf.options.resolvers.enum(compact(values)) || [];
+      },
       $ref(values: unknown) {
         return {};
       },