👍 Add UnsupportedHostingServiceError error

Now `getHostingService` throws `UnsupportedHostingServiceError` error
when the hosting service is not supported.

Author: lambdalisue

hosting_service/mod.ts

@@ -26,8 +26,26 @@ export async function getHostingService(
 ): Promise<HostingService> {
   const hostname = aliases?.[fetchURL.hostname] ?? fetchURL.hostname;
   const svcName = hostname.replace(/\W/g, "_");
-  const svc = await import(
-    new URL(`./services/${svcName}.ts`, import.meta.url).href
-  );
-  return svc.service;
+  try {
+    const svc = await import(
+      new URL(`./services/${svcName}.ts`, import.meta.url).href
+    );
+    return svc.service;
+  } catch (err: unknown) {
+    if (err instanceof TypeError) {
+      // TypeError: Module not found "...".
+      throw new UnsupportedHostingServiceError(hostname, svcName);
+    }
+    throw err;
+  }
+}
+
+export class UnsupportedHostingServiceError extends Error {
+  constructor(
+    public hostname: string,
+    public svcName: string,
+  ) {
+    super(`Unsupported hosting service: ${hostname} (${svcName})`);
+    this.name = this.constructor.name;
+  }
 }

hosting_service/mod_test.ts

@@ -1,12 +1,22 @@
-import { assertSnapshot } from "https://deno.land/[email protected]/testing/snapshot.ts";
-import { getHostingService } from "./mod.ts";
+import { assertRejects } from "https://deno.land/[email protected]/assert/mod.ts";
+import { assertSnapshot } from "https://deno.land/[email protected]/testing/snapshot.ts";
+import { getHostingService, UnsupportedHostingServiceError } from "./mod.ts";
 
 Deno.test("getHostingService", async (t) => {
+  await t.step("throws error for unsupported hosting service", async () => {
+    const url = new URL("https://example.com/lambdalisue/gin.vim");
+    await assertRejects(
+      () => {
+        return getHostingService(url);
+      },
+      UnsupportedHostingServiceError,
+    );
+  });
+
   const urls = [
     new URL("ssh://[email protected]/lambdalisue/gin.vim"),
     new URL("https://github.com/lambdalisue/gin.vim"),
   ];
-
   for (const url of urls) {
     const svc = await getHostingService(url);