feat: all static page types are inferred

TODO
- Create a union type of all possible paths given the pages
- Update tests and refactor examples to match new api

packages/waku/src/router/create-pages.ts

@@ -47,6 +47,12 @@ type Split<Str extends string, Del extends string | number> = string extends Str
       ? [T, ...Split<U, Del>]
       : [Str];
 
+/**
+ * This helper makes types more readable
+ * @see https://www.totaltypescript.com/concepts/the-prettify-helper
+ */
+type Prettify<T> = { [K in keyof T]: T[K] } & {};
+
 /** Assumes that the path is a part of a slug path. */
 type IsValidPathItem<T> = T extends `/${infer _}`
   ? false
@@ -144,33 +150,46 @@ export type CreatePage = <
   PagePath extends string,
   SlugKey extends string,
   WildSlugKey extends string,
+  Render extends 'static' | 'dynamic',
 >(
   page: (
     | {
-        render: 'static';
+        render: Extract<Render, 'static'>;
         path: PathWithoutSlug<PagePath>;
         component: FunctionComponent<RouteProps>;
       }
     | {
-        render: 'static';
+        render: Extract<Render, 'static'>;
         path: PathWithStaticSlugs<PagePath>;
         staticPaths: StaticSlugRoutePaths<PagePath>;
         component: FunctionComponent<RouteProps & Record<SlugKey, string>>;
       }
     | {
-        render: 'dynamic';
+        render: Extract<Render, 'dynamic'>;
         path: PathWithoutSlug<PagePath>;
         component: FunctionComponent<RouteProps>;
       }
     | {
-        render: 'dynamic';
+        render: Extract<Render, 'dynamic'>;
         path: PathWithWildcard<PagePath, SlugKey, WildSlugKey>;
         component: FunctionComponent<
           RouteProps & Record<SlugKey, string> & Record<WildSlugKey, string[]>
         >;
       }
   ) & { unstable_disableSSR?: boolean },
-) => PagePath;
+) => Prettify<
+  Omit<
+    Exclude<typeof page, { path: never } | { render: never }>,
+    'unstable_disableSSR'
+  >
+>;
+
+/** Generic type that represents any page. This is used to infer the return type of createPages. */
+type AnyPage = {
+  path: string;
+  render: 'static' | 'dynamic';
+  staticPaths?: string[];
+};
 
 export type CreateLayout = <T extends string>(layout: {
   render: 'static' | 'dynamic';
@@ -180,7 +199,7 @@ export type CreateLayout = <T extends string>(layout: {
   >;
 }) => void;
 
-export function createPages<AllPages extends string[]>(
+export function createPages<AllPages extends AnyPage[]>(
   fn: (fns: {
     createPage: CreatePage;
     createLayout: CreateLayout;
@@ -297,7 +316,7 @@ export function createPages<AllPages extends string[]>(
     } else {
       throw new Error('Invalid page configuration');
     }
-    return page.path;
+    return page as Exclude<typeof page, { path: never } | { render: never }>;
   };
 
   const createLayout: CreateLayout = (layout) => {

packages/waku/src/router/test.tsx

@@ -33,6 +33,4 @@ export const router = createPages(async ({ createPage }) => {
 // Note: This abstracts away the return type from the final router
 type Router = typeof router;
 
-type InferredRouterPath = Awaited<
-  NonNullable<Router['DO_NOT_USE_ready']>
->[number];
+type InferredRouter = Awaited<NonNullable<Router['DO_NOT_USE_ready']>>[number];