Yarn 4 Migration (#32253)

Migrates the Overleaf monorepo package manager from npm (v11) to Yarn 4 (v4.9.1) using node-modules linker mode.

GitOrigin-RevId: 50d32ab01955c15e29679eff9e9e9cfb897fab2d

services/filestore/test/unit/setup.js

@@ -4,7 +4,32 @@ import mongodb from 'mongodb'
 import sinonChai from 'sinon-chai'
 import chaiAsPromised from 'chai-as-promised'
 
+// Workaround: vitest's built-in chai plugins register spy-related properties
+// (e.g. callCount) as getter-only via addChainableMethod. sinon-chai then tries
+// to overwrite them via addMethod (plain property assignment), which fails.
+// Pre-delete the conflicting getter-only properties so the assignment succeeds.
+const sinonChaiMethodProps = [
+  'callCount',
+  'calledBefore',
+  'calledAfter',
+  'calledImmediatelyBefore',
+  'calledImmediatelyAfter',
+  'calledOn',
+  'calledWith',
+  'calledOnceWith',
+  'calledWithExactly',
+  'calledOnceWithExactly',
+  'calledWithMatch',
+  'returned',
+  'thrown',
+]
+for (const name of sinonChaiMethodProps) {
+  if (Object.getOwnPropertyDescriptor(chai.Assertion.prototype, name)?.get) {
+    delete chai.Assertion.prototype[name]
+  }
+}
 chai.use(sinonChai)
+
 chai.use(chaiAsPromised)
 
 // ensure every ObjectId has the id string as a property for correct comparisons