chore: inline file traversal function

package.json

@@ -9,9 +9,6 @@
   "engines": {
     "node": "^18.20.0 || ^20.10.0 || >=22.0.0"
   },
-  "dependencies": {
-    "empathic": "^2.0.1"
-  },
   "peerDependencies": {
     "@babel/core": "^7.12.0 || ^8.0.0-beta.1",
     "@rspack/core": "^1.0.0 || ^2.0.0-0",

src/cache.js

@@ -12,8 +12,8 @@ const os = require("os");
 const path = require("path");
 const zlib = require("zlib");
 const { promisify } = require("util");
+const { lstatSync } = require("fs");
 const { readFile, writeFile, mkdir } = require("fs/promises");
-const { up: findUpSync } = require("empathic/find");
 const { env } = process;
 const transform = require("./transform");
 const serialize = require("./serialize");
@@ -274,14 +274,32 @@ function findCacheDir(name) {
   if (env.CACHE_DIR && !["true", "false", "1", "0"].includes(env.CACHE_DIR)) {
     return path.join(env.CACHE_DIR, name);
   }
-  const rootPkgJSONPath = findUpSync("package.json");
-  if (rootPkgJSONPath) {
-    return path.join(
-      path.dirname(rootPkgJSONPath),
-      "node_modules",
-      ".cache",
-      name,
-    );
+  const rootPkgJSONPath = findPackageRoot();
+  if (rootPkgJSONPath !== null) {
+    return path.join(rootPkgJSONPath, "node_modules", ".cache", name);
   }
   return os.tmpdir();
 }
+
+/**
+ * Find the package root directory.
+ * @returns {string | null}
+ */
+function findPackageRoot() {
+  let current = process.cwd();
+  let previous;
+
+  while (current !== previous) {
+    try {
+      if (lstatSync(path.join(current, "package.json")).isFile()) {
+        return current;
+      }
+    } catch {
+      // empty
+    }
+    previous = current;
+    current = path.dirname(current);
+  }
+
+  return null;
+}

yarn.lock

@@ -1941,7 +1941,6 @@ __metadata:
     "@rspack/core": "npm:^1.7.5"
     "@types/node": "npm:^18.19.130"
     c8: "npm:^11.0.0"
-    empathic: "npm:^2.0.1"
     eslint: "npm:^10.6.0"
     eslint-config-prettier: "npm:^10.1.8"
     globals: "npm:^17.7.0"