From 5190c2d76fb4f8ee48abe8df9eb198829002eb77 Mon Sep 17 00:00:00 2001
From: Gustav Hansen <gustav.hansen@sanity.io>
Date: Wed, 20 May 2026 11:15:20 +0200
Subject: [PATCH] test(cli): stub getWindowSize in vitest worker setup

`@oclif/core/lib/screen.js` reads `process.stdout.getWindowSize()` once,
at module init, but only if `process.stdout.isTTY` is truthy. Vitest's
stdout proxy doesn't implement `getWindowSize`, so when a test sets
`isTTY = true` before oclif is loaded in that worker (the situation in
`checkForUpdates.test.ts`), screen.js crashes the whole worker with
`TypeError: stream.getWindowSize is not a function`.

It's order-dependent: only the shard where checkForUpdates is the first
oclif-touching file flakes, which is why we see different individual
tests fail across shards in CI.

Install a `getWindowSize` shim once per worker so screen.js can load
safely no matter when isTTY gets flipped.
---
 packages/@sanity/cli/test/setup.ts | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/packages/@sanity/cli/test/setup.ts b/packages/@sanity/cli/test/setup.ts
index d29aa8d48..056f143e9 100644
--- a/packages/@sanity/cli/test/setup.ts
+++ b/packages/@sanity/cli/test/setup.ts
@@ -5,3 +5,18 @@ import {vi} from 'vitest'
  */
 // Mock open, to prevent it from opening a browser
 vi.mock('open')
+
+// `@oclif/core/lib/screen.js` reads `process.stdout.getWindowSize()` at module
+// init when `process.stdout.isTTY` is truthy. Vitest's stdout proxy doesn't
+// implement `getWindowSize`, so any test that flips `isTTY = true` before oclif
+// is loaded (e.g. `checkForUpdates.test.ts`) crashes the whole worker.
+// Provide a no-op shim once per worker so the eventual load is safe.
+for (const stream of [process.stdout, process.stderr] as const) {
+  if (typeof stream.getWindowSize !== 'function') {
+    Object.defineProperty(stream, 'getWindowSize', {
+      configurable: true,
+      value: () => [80, 24],
+      writable: true,
+    })
+  }
+}