fix(remix-dev): re-use REMIX_DEV_SERVER_WS_PORT when reloading config (#3206)

Co-authored-by: Kent C. Dodds <me+github@kentcdodds.com>

Author: mcansh

packages/remix-dev/__tests__/readConfig-test.ts

@@ -52,4 +52,9 @@ describe("readConfig", () => {
     `
     );
   });
+
+  it("returns the same devServerPort value across reloads", async () => {
+    let newConfig = await readConfig(remixRoot);
+    expect(newConfig.devServerPort).toBe(config.devServerPort);
+  });
 });

packages/remix-dev/config.ts

@@ -353,12 +353,7 @@ export async function readConfig(
       path.join("public", "build")
   );
 
-  if (typeof appConfig.devServerPort !== "number") {
-    appConfig.devServerPort = Number(
-      process.env.REMIX_DEV_SERVER_WS_PORT || 8002
-    );
-  }
-  let devServerPort = await getPort({ port: appConfig.devServerPort });
+  let devServerPort = Number(process.env.REMIX_DEV_SERVER_WS_PORT) || await getPort({ port: Number(appConfig.devServerPort) || undefined });
   // set env variable so un-bundled servers can use it
   process.env.REMIX_DEV_SERVER_WS_PORT = `${devServerPort}`;
   let devServerBroadcastDelay = appConfig.devServerBroadcastDelay || 0;