feat(core): c.responses utility (#539)

Co-authored-by: Youssef Gaber <1728215+Gabrola@users.noreply.github.com>

Author: ToTeTo

.changeset/shaggy-lizards-rhyme.md

@@ -0,0 +1,5 @@
+---
+'@ts-rest/core': minor
+---
+
+Add `c.responses` utility

libs/ts-rest/core/src/lib/dsl.spec.ts

@@ -347,7 +347,7 @@ describe('contract', () => {
         method: 'GET',
         path: '/posts/:id',
         responses: {
-          200: c.body<{ id: number }>(),
+          200: c.type<{ id: number }>(),
         },
       },
     });
@@ -370,14 +370,111 @@ describe('contract', () => {
     >;
   });
 
+  it('should be typed correctly with separate query route', () => {
+    const getPost = c.query({
+      method: 'GET',
+      path: '/posts/:id',
+      responses: {
+        200: c.type<{ id: number }>(),
+      },
+    });
+
+    const contract = c.router({
+      getPost,
+    });
+
+    type ContractShape = Expect<
+      Equal<
+        typeof contract,
+        {
+          getPost: {
+            method: 'GET';
+            path: '/posts/:id';
+            responses: {
+              200: ContractPlainType<{
+                id: number;
+              }>;
+            };
+          };
+        }
+      >
+    >;
+  });
+
+  it('should be typed correctly with separate mutation route', () => {
+    const createPost = c.mutation({
+      method: 'POST',
+      path: '/posts',
+      responses: {
+        200: c.type<{ id: number }>(),
+      },
+      body: c.type<{ title: string }>(),
+    });
+
+    const contract = c.router({
+      createPost,
+    });
+
+    type ContractShape = Expect<
+      Equal<
+        typeof contract,
+        {
+          createPost: {
+            method: 'POST';
+            path: '/posts';
+            responses: {
+              200: ContractPlainType<{
+                id: number;
+              }>;
+            };
+            body: ContractPlainType<{
+              title: string;
+            }>;
+          };
+        }
+      >
+    >;
+  });
+
+  it('should be typed correctly with separate responses', () => {
+    const responses = c.responses({
+      200: c.type<{ id: number }>(),
+    });
+
+    const contract = c.router({
+      getPost: {
+        method: 'GET',
+        path: '/posts/:id',
+        responses,
+      },
+    });
+
+    type ContractShape = Expect<
+      Equal<
+        typeof contract,
+        {
+          getPost: {
+            method: 'GET';
+            path: '/posts/:id';
+            responses: {
+              200: ContractPlainType<{
+                id: number;
+              }>;
+            };
+          };
+        }
+      >
+    >;
+  });
+
   it('should add strictStatusCodes=true option to routes', () => {
     const contract = c.router(
       {
         getPost: {
           method: 'GET',
           path: '/posts/:id',
           responses: {
-            200: c.body<{ id: number }>(),
+            200: c.type<{ id: number }>(),
           },
         },
       },
@@ -405,7 +502,7 @@ describe('contract', () => {
           method: 'GET',
           path: '/posts/:id',
           responses: {
-            200: c.body<{ id: number }>(),
+            200: c.type<{ id: number }>(),
           },
         },
       },
@@ -433,7 +530,7 @@ describe('contract', () => {
           method: 'GET',
           path: '/posts/:id',
           responses: {
-            200: c.body<{ id: number }>(),
+            200: c.type<{ id: number }>(),
           },
           strictStatusCodes: true,
         },
@@ -462,7 +559,7 @@ describe('contract', () => {
           method: 'GET',
           path: '/posts/:id',
           responses: {
-            200: c.body<{ id: number }>(),
+            200: c.type<{ id: number }>(),
           },
           strictStatusCodes: false,
         },

libs/ts-rest/core/src/lib/dsl.ts

@@ -177,6 +177,10 @@ export const isAppRoute = (obj: AppRoute | AppRouter): obj is AppRoute => {
   return 'method' in obj && 'path' in obj;
 };
 
+type NarrowObject<T> = {
+  [K in keyof T]: T[K];
+};
+
 /**
  * The instantiated ts-rest client
  */
@@ -196,12 +200,20 @@ type ContractInstance = {
    * A single query route, should exist within
    * a {@link AppRouter}
    */
-  query: <T extends AppRouteQuery>(query: T) => T;
+  query: <T extends AppRouteQuery>(query: NarrowObject<T>) => T;
   /**
    * A single mutation route, should exist within
    * a {@link AppRouter}
    */
-  mutation: <T extends AppRouteMutation>(mutation: T) => T;
+  mutation: <T extends AppRouteMutation>(mutation: NarrowObject<T>) => T;
+  responses: <
+    TResponses extends Record<
+      number,
+      ContractAnyType | ContractOtherResponse<ContractAnyType>
+    >,
+  >(
+    responses: NarrowObject<TResponses>,
+  ) => TResponses;
   /**
    * @deprecated Please use type() instead.
    */
@@ -276,6 +288,7 @@ export const initContract = (): ContractInstance => {
     router: (endpoints, options) => recursivelyApplyOptions(endpoints, options),
     query: (args) => args,
     mutation: (args) => args,
+    responses: (args) => args,
     response: () => ContractPlainTypeRuntimeSymbol,
     body: () => ContractPlainTypeRuntimeSymbol,
     type: () => ContractPlainTypeRuntimeSymbol,