Avoid creating node_modules/.cache/ when --cache is not enabled (#18124)

Co-authored-by: fisker Cheung <lionkay@gmail.com>

changelog_unreleased/cli/18124.md

@@ -0,0 +1,3 @@
+#### Avoid creating `node_modules/.cache/` directory when `--cache` is not enabled (#18124 by @chiawendt)
+
+Run `prettier .` without `--cache` no longer creates an empty `node_modules/.cache/` directory.

src/cli/find-cache-file.js

@@ -8,8 +8,7 @@ import { isJson, statSafe } from "./utils.js";
  * Find default cache file (`./node_modules/.cache/prettier/.prettier-cache`) using https://github.com/sindresorhus/find-cache-directory
  */
 function findDefaultCacheFile() {
-  const cacheDir =
-    findCacheDirectory({ name: "prettier", create: true }) || os.tmpdir();
+  const cacheDir = findCacheDirectory({ name: "prettier" }) ?? os.tmpdir();
   const cacheFilePath = path.join(cacheDir, ".prettier-cache");
   return cacheFilePath;
 }

tests/integration/__tests__/cache.js

@@ -57,6 +57,18 @@ describe("--cache option", () => {
   });
   afterAll(clean);
 
+  it("creates cache file with --cache", async () => {
+    await runCliWithoutGitignore(dir, ["--cache", "a.js"]);
+    await expect(fs.stat(defaultCacheFile)).resolves.not.toThrow();
+  });
+
+  it("doesn't create cache directory without --cache", async () => {
+    await runCliWithoutGitignore(dir, ["a.js"]);
+    await expect(
+      fs.stat(path.join(dir, "node_modules/.cache")),
+    ).rejects.toHaveProperty("code", "ENOENT");
+  });
+
   it("throw error when cache-strategy is invalid", async () => {
     const { stderr } = await runCliWithoutGitignore(dir, [
       "--cache",