fix(types): infer types correctly when method is omitted (#2551)

Author: danielroe

src/types/fetch/fetch.ts

@@ -78,7 +78,13 @@ export interface $Fetch<
   >(
     request: R,
     opts?: O
-  ): Promise<TypedInternalResponse<R, T, ExtractedRouteMethod<R, O>>>;
+  ): Promise<
+    TypedInternalResponse<
+      R,
+      T,
+      NitroFetchOptions<R> extends O ? "get" : ExtractedRouteMethod<R, O>
+    >
+  >;
   raw<
     T = DefaultT,
     R extends NitroFetchRequest = DefaultR,
@@ -87,7 +93,13 @@ export interface $Fetch<
     request: R,
     opts?: O
   ): Promise<
-    FetchResponse<TypedInternalResponse<R, T, ExtractedRouteMethod<R, O>>>
+    FetchResponse<
+      TypedInternalResponse<
+        R,
+        T,
+        NitroFetchOptions<R> extends O ? "get" : ExtractedRouteMethod<R, O>
+      >
+    >
   >;
   create<T = DefaultT, R extends NitroFetchRequest = DefaultR>(
     defaults: FetchOptions

test/fixture/types.ts

@@ -183,6 +183,13 @@ describe("API routes", () => {
   });
 
   it("generates the correct type depending on the method used", () => {
+    expectTypeOf($fetch("/api/methods")).toEqualTypeOf<Promise<"Index get">>();
+    expectTypeOf($fetch("/api/methods", {})).toEqualTypeOf<
+      Promise<"Index get">
+    >();
+    expectTypeOf($fetch("/api/methods", { query: {} })).toEqualTypeOf<
+      Promise<"Index get">
+    >();
     expectTypeOf($fetch("/api/methods", { method: "get" })).toEqualTypeOf<
       Promise<"Index get">
     >();