avoid using same port number for test (#4147)

1 files changed, 5 insertions, 3 deletions

diff --git a/std/examples/tests/echo_server_test.ts b/std/examples/tests/echo_server_test.ts
index 20fd7479c..3c1893342 100644
--- a/std/examples/tests/echo_server_test.ts
+++ b/std/examples/tests/echo_server_test.ts
@@ -1,12 +1,14 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 import { assertStrictEq, assertNotEquals } from "../../testing/asserts.ts";
 import { BufReader, ReadLineResult } from "../../io/bufio.ts";
+import { randomPort } from "../../http/test_util.ts";
+const port = randomPort();
 
 Deno.test("[examples/echo_server]", async () => {
   const encoder = new TextEncoder();
   const decoder = new TextDecoder();
   const process = Deno.run({
-    args: [Deno.execPath(), "--allow-net", "echo_server.ts"],
+    args: [Deno.execPath(), "--allow-net", "echo_server.ts", `${port}`],
     cwd: "examples",
     stdout: "piped"
   });
@@ -19,10 +21,10 @@ Deno.test("[examples/echo_server]", async () => {
     assertNotEquals(message, Deno.EOF);
     assertStrictEq(
       decoder.decode((message as ReadLineResult).line).trim(),
-      "Listening on 0.0.0.0:8080"
+      "Listening on 0.0.0.0:" + port
     );
 
-    conn = await Deno.connect({ hostname: "127.0.0.1", port: 8080 });
+    conn = await Deno.connect({ hostname: "127.0.0.1", port });
     const connReader = new BufReader(conn);
 
     await conn.write(encoder.encode("Hello echo_server\n"));