allow for null or undefined search params

package.json

@@ -1,6 +1,6 @@
 {
   "name": "route-fn",
-  "version": "1.1.0",
+  "version": "1.1.1",
   "description": "A simple utility function for typesafe urls.",
   "license": "MIT",
   "type": "module",

src/index.ts

@@ -28,9 +28,13 @@ export function createRouteFn<const Routes extends string[]>(routes: Routes) {
     for (const key in params) {
       if (key === "searchParams") {
         const searchParams = new URLSearchParams(
-          params.searchParams as Record<string, string>
+          Object.fromEntries(
+            Object.entries(params.searchParams ?? {})
+              .filter(([, value]) => value !== null && value !== undefined)
+              .map(([key, value]) => [key, value!.toString()])
+          )
         )
-        url += `?${searchParams.toString()}`
+        url += searchParams.size ? `?${searchParams.toString()}` : ""
       } else {
         const param = (params as Record<string, string>)[key]!
         url = url.replace(`:${key}`, param)

src/types.ts

@@ -60,7 +60,7 @@ export type RouteIdParams<Id extends string> = Record<
 >
 
 export type SearchParams = {
-  searchParams?: Record<string, string | number>
+  searchParams?: Record<string, string | number | null | undefined>
 }
 
 export type RouteParams<Id extends string> = Prettify<

tests/index.test.ts

@@ -22,13 +22,27 @@ describe("route-fn", () => {
   })
 
   it("should return the correct route with search params", async () => {
-    const route = createRouteFn(["/account", "/user/:id"])
+    const route = createRouteFn(["/user/:id"])
 
+    expect(route("/user/:id", { id: 1, searchParams: { page: 0 } })).toBe(
+      "/user/1?page=0"
+    )
     expect(route("/user/:id", { id: 1, searchParams: { page: 2 } })).toBe(
       "/user/1?page=2"
     )
   })
 
+  it("should strip null or undefined search params", async () => {
+    const route = createRouteFn(["/user/:id"])
+
+    expect(route("/user/:id", { id: 1, searchParams: { page: null } })).toBe(
+      "/user/1"
+    )
+    expect(
+      route("/user/:id", { id: 1, searchParams: { page: undefined } })
+    ).toBe("/user/1")
+  })
+
   it("should show type error when a param is missing", async () => {
     const route = createRouteFn(["/user/:id/settings/:page"])