fix: support PORT=0 for random port assignment (#4000)

Author: wadefletch

src/presets/bun/runtime/bun.ts

@@ -8,7 +8,8 @@ import { startScheduleRunner } from "#nitro/runtime/task";
 import { trapUnhandledErrors } from "#nitro/runtime/error/hooks";
 import { resolveWebsocketHooks } from "#nitro/runtime/app";
 
-const port = Number.parseInt(process.env.NITRO_PORT || process.env.PORT || "") || 3000;
+const _parsedPort = Number.parseInt(process.env.NITRO_PORT ?? process.env.PORT ?? "");
+const port = Number.isNaN(_parsedPort) ? 3000 : _parsedPort;
 const host = process.env.NITRO_HOST || process.env.HOST;
 const cert = process.env.NITRO_SSL_CERT;
 const key = process.env.NITRO_SSL_KEY;

src/presets/deno/runtime/deno-server.ts

@@ -8,7 +8,8 @@ import { startScheduleRunner } from "#nitro/runtime/task";
 import { trapUnhandledErrors } from "#nitro/runtime/error/hooks";
 import { resolveWebsocketHooks } from "#nitro/runtime/app";
 
-const port = Number.parseInt(process.env.NITRO_PORT || process.env.PORT || "") || 3000;
+const _parsedPort = Number.parseInt(process.env.NITRO_PORT ?? process.env.PORT ?? "");
+const port = Number.isNaN(_parsedPort) ? 3000 : _parsedPort;
 
 const host = process.env.NITRO_HOST || process.env.HOST;
 const cert = process.env.NITRO_SSL_CERT;

src/presets/node/runtime/node-cluster.ts

@@ -8,7 +8,8 @@ import { startScheduleRunner } from "#nitro/runtime/task";
 import { trapUnhandledErrors } from "#nitro/runtime/error/hooks";
 import { resolveWebsocketHooks } from "#nitro/runtime/app";
 
-const port = Number.parseInt(process.env.NITRO_PORT || process.env.PORT || "") || 3000;
+const _parsedPort = Number.parseInt(process.env.NITRO_PORT ?? process.env.PORT ?? "");
+const port = Number.isNaN(_parsedPort) ? 3000 : _parsedPort;
 
 const host = process.env.NITRO_HOST || process.env.HOST;
 const cert = process.env.NITRO_SSL_CERT;

src/presets/node/runtime/node-server.ts

@@ -7,7 +7,8 @@ import { startScheduleRunner } from "#nitro/runtime/task";
 import { trapUnhandledErrors } from "#nitro/runtime/error/hooks";
 import { resolveWebsocketHooks } from "#nitro/runtime/app";
 
-const port = Number.parseInt(process.env.NITRO_PORT || process.env.PORT || "") || 3000;
+const _parsedPort = Number.parseInt(process.env.NITRO_PORT ?? process.env.PORT ?? "");
+const port = Number.isNaN(_parsedPort) ? 3000 : _parsedPort;
 
 const host = process.env.NITRO_HOST || process.env.HOST;
 const cert = process.env.NITRO_SSL_CERT;