Add normalizer rule for required on allOf

src/normalizer.ts

@@ -145,6 +145,15 @@ rules.set('Transform const to singleton enum', schema => {
   }
 })
 
+rules.set('Spread required on allOf into its subSchema', schema => {
+  if (schema.allOf && schema.required) {
+    const schemaRequired = schema.required
+    schema.allOf.forEach(subSchema => {
+      subSchema.required = [...(subSchema.required || []), ...schemaRequired]
+    })
+  }
+})
+
 export function normalize(rootSchema: LinkedJSONSchema, filename: string, options: Options): NormalizedJSONSchema {
   rules.forEach(rule => traverse(rootSchema, schema => rule(schema, filename, options)))
   return rootSchema as NormalizedJSONSchema

test/__snapshots__/test/test.ts.md

@@ -9021,3 +9021,62 @@ Generated by [AVA](https://avajs.dev).
         ""␊
       ]␊
     }`
+
+## Spread required on AllOf into its sub-schema
+
+> Snapshot 1
+
+    `{␊
+      "type": "object",␊
+      "properties": {␊
+        "reference": {␊
+          "allOf": [␊
+            {␊
+              "$ref": "#/definitions/defined",␊
+              "required": [␊
+                "subproperty"␊
+              ]␊
+            }␊
+          ],␊
+          "required": [␊
+            "subproperty"␊
+          ]␊
+        }␊
+      },␊
+      "definitions": {␊
+        "defined": {␊
+          "type": "object",␊
+          "properties": {␊
+            "subproperty": {␊
+              "type": "integer"␊
+            }␊
+          },␊
+          "required": [],␊
+          "additionalProperties": true␊
+        }␊
+      },␊
+      "additionalProperties": false,␊
+      "required": [],␊
+      "id": "RequiredOnAllOf"␊
+    }`
+
+## mergeRequiredFromAllOf.js
+
+> Expected output to match snapshot for e2e test: mergeRequiredFromAllOf.js
+
+    `/* tslint:disable */␊
+    /**␊
+     * This file was automatically generated by json-schema-to-typescript.␊
+     * DO NOT MODIFY IT BY HAND. Instead, modify the source JSONSchema file,␊
+     * and run json-schema-to-typescript to regenerate this file.␊
+     */␊
+    ␊
+    export interface MergeRequiredFromAllOf {␊
+      reference?: Defined;␊
+    }␊
+    export interface Defined {␊
+      foo: number;␊
+      bar: string;␊
+      [k: string]: unknown;␊
+    }␊
+    `

test/e2e/mergeRequiredFromAllOf.ts

@@ -0,0 +1,31 @@
+export const input = {
+  title: 'MergeRequiredFromAllOf',
+  type: 'object',
+  properties: {
+    reference: {
+      allOf: [
+        {
+          $ref: '#/definitions/defined'
+        }
+      ],
+      required: ['foo']
+    }
+  },
+  definitions: {
+    defined: {
+      additionalProperties: true,
+      type: 'object',
+      properties: {
+        foo: {
+          type: 'integer'
+        },
+        bar: {
+          type: 'string'
+        }
+      },
+      required: ['bar']
+    }
+  },
+  required: [],
+  additionalProperties: false
+}

test/normalizer/requiredOnAllOf.json

@@ -0,0 +1,62 @@
+{
+  "name": "Spread required on AllOf into its sub-schema",
+  "in": {
+    "type": "object",
+    "properties": {
+      "reference": {
+        "allOf": [
+          {
+            "$ref": "#/definitions/defined"
+          }
+        ],
+        "required": [
+          "subproperty"
+        ]
+      }
+    },
+    "definitions": {
+      "defined": {
+        "type": "object",
+        "properties": {
+          "subproperty": {
+            "type": "integer"
+          }
+        }
+      }
+    },
+    "additionalProperties": false
+  },
+  "out": {
+    "id": "RequiredOnAllOf",
+    "type": "object",
+    "properties": {
+      "reference": {
+        "allOf": [
+          {
+            "$ref": "#/definitions/defined",
+            "required": [
+              "subproperty"
+            ]
+          }
+        ],
+        "required": [
+          "subproperty"
+        ]
+      }
+    },
+    "definitions": {
+      "defined": {
+        "additionalProperties": true,
+        "type": "object",
+        "properties": {
+          "subproperty": {
+            "type": "integer"
+          }
+        },
+        "required": []
+      }
+    },
+    "required": [],
+    "additionalProperties": false
+  }
+}