avoid EBUSY when deleting fixture dir on windows

src/fixture/src/index.ts

@@ -100,6 +100,10 @@ export class TestFixtures {
       const { onEOF } = this.#t
       this.#t.onEOF = async () => {
         this.#t.onEOF = onEOF
+        if (relative(process.cwd(), dir) === '') {
+          // cd out of it first, or else Windows fails with EBUSY every time
+          process.chdir(dirname(dir))
+        }
         await rimraf(dir)
         await onEOF()
       }

src/fixture/test/index.ts

@@ -5,6 +5,7 @@ import {
   rmdirSync,
   writeFileSync,
 } from 'fs'
+import { relative } from 'path'
 import t from 'tap'
 import { plugin } from '../dist/esm/index.js'
 
@@ -86,3 +87,17 @@ t.test('change testdirName', t => {
   })
   t.end()
 })
+
+t.test('cd out of dir before deleting', t => {
+  let dir: string
+  t.test('chdir into testdir', t => {
+    process.chdir(t.testdir({}))
+    dir = t.testdirName
+    t.end()
+  })
+  t.test('got kicked up a level', t => {
+    t.equal(relative(dir, process.cwd()), '..')
+    t.end()
+  })
+  t.end()
+})