fix https://github.com/photostructure/fs-metadata/security/code-scann…

…ing/8
photostructure · Jan 9, 2025 · edc1a86 · edc1a86
1 parent a08cf0a
commit edc1a86
Show file tree

Hide file tree

Showing 2 changed files with 13 additions and 5 deletions.
diff --git a/src/path.test.ts b/src/path.test.ts
@@ -19,6 +19,7 @@ describe("mount_point", () => {
     });
 
     it("handles multiple trailing slashes", () => {
+      expect(normalizePosixPath("//")).toBe("/");
       expect(normalizePosixPath("/home//")).toBe("/home");
       expect(normalizePosixPath("/usr////")).toBe("/usr");
     });

diff --git a/src/path.ts b/src/path.ts
@@ -24,11 +24,18 @@ export function normalizePath(
 export function normalizePosixPath(
   mountPoint: string | undefined,
 ): string | undefined {
-  return isBlank(mountPoint)
-    ? undefined
-    : mountPoint === "/"
-      ? mountPoint
-      : mountPoint.replace(/\/+$/, "");
+  if (isBlank(mountPoint)) return undefined;
+  if (mountPoint === "/") return mountPoint;
+
+  // Fast path: check last char only if no trailing slash
+  if (mountPoint[mountPoint.length - 1] !== "/") return mountPoint;
+
+  // Slower path: trim trailing slashes
+  let end = mountPoint.length - 1;
+  while (end > 0 && mountPoint[end] === "/") {
+    end--;
+  }
+  return mountPoint.slice(0, end + 1);
 }
 
 /**