1 files changed, 49 insertions, 0 deletions

diff --git a/packages/turbo-utils/src/getTurboRoot.ts b/packages/turbo-utils/src/getTurboRoot.ts
new file mode 100644
index 0000000..64a37be
--- /dev/null
+++ b/packages/turbo-utils/src/getTurboRoot.ts
@@ -0,0 +1,49 @@
+import { findRootSync } from "@manypkg/find-root";
+import searchUp from "./searchUp";
+import JSON5 from "json5";
+
+interface Options {
+  cache?: boolean;
+}
+
+function contentCheck(content: string): boolean {
+  const result = JSON5.parse(content);
+  return !result.extends;
+}
+
+const configCache: Record<string, string> = {};
+
+function getTurboRoot(cwd?: string, opts?: Options): string | null {
+  const cacheEnabled = opts?.cache ?? true;
+  const currentDir = cwd || process.cwd();
+
+  if (cacheEnabled && configCache[currentDir]) {
+    return configCache[currentDir];
+  }
+
+  // Turborepo root can be determined by a turbo.json without an extends key
+  let root = searchUp({
+    target: "turbo.json",
+    cwd: currentDir,
+    contentCheck,
+  });
+
+  if (!root) {
+    try {
+      root = findRootSync(currentDir);
+      if (!root) {
+        return null;
+      }
+    } catch (err) {
+      return null;
+    }
+  }
+
+  if (cacheEnabled) {
+    configCache[currentDir] = root;
+  }
+
+  return root;
+}
+
+export default getTurboRoot;