fix(ext/node): add WriteStream.isTTY (#21801)

2 files changed, 7 insertions, 0 deletions

diff --git a/cli/tests/unit_node/tty_test.ts b/cli/tests/unit_node/tty_test.ts
index ca8809685..c393da5b3 100644
--- a/cli/tests/unit_node/tty_test.ts
+++ b/cli/tests/unit_node/tty_test.ts
@@ -3,6 +3,7 @@
 
 import { assert } from "../../../test_util/std/assert/mod.ts";
 import { isatty } from "node:tty";
+import process from "node:process";
 
 Deno.test("[node/tty isatty] returns true when fd is a tty, false otherwise", () => {
   assert(Deno.isatty(Deno.stdin.rid) === isatty(Deno.stdin.rid));
@@ -29,3 +30,8 @@ Deno.test("[node/tty isatty] returns false for irrelevant values", () => {
   assert(!isatty(null as any));
   assert(!isatty(undefined as any));
 });
+
+Deno.test("[node/tty WriteStream.isTTY] returns true when fd is a tty", () => {
+  assert(Deno.isatty(Deno.stdin.rid) === process.stdin.isTTY);
+  assert(Deno.isatty(Deno.stdout.rid) === process.stdout.isTTY);
+});
diff --git a/ext/node/polyfills/tty.js b/ext/node/polyfills/tty.js
index e6c9c10c1..a08d1ae37 100644
--- a/ext/node/polyfills/tty.js
+++ b/ext/node/polyfills/tty.js
@@ -79,6 +79,7 @@ export class WriteStream extends Socket {
     const { columns, rows } = Deno.consoleSize();
     this.columns = columns;
     this.rows = rows;
+    this.isTTY = true;
   }
 }