diff --git a/src/libutil/tests/tests.cc b/src/libutil/tests/tests.cc
index 1b016430d..d46f6a5a4 100644
--- a/src/libutil/tests/tests.cc
+++ b/src/libutil/tests/tests.cc
@@ -127,11 +127,9 @@ namespace nix {
         ASSERT_EQ(p1, "");
     }
 
-    // XXX: according to the doc of `baseNameOf`, baseNameOf("/dir/") should return
-    // "" but it actually returns "dir"
-    TEST(baseNameOf, DISABLED_trailingSlash) {
+    TEST(baseNameOf, trailingSlash) {
         auto p1 = baseNameOf("/dir/");
-        ASSERT_EQ(p1, "");
+        ASSERT_EQ(p1, "dir");
     }
 
     /* ----------------------------------------------------------------------------
diff --git a/src/libutil/util.hh b/src/libutil/util.hh
index 38a0f7a5c..a63ee05b3 100644
--- a/src/libutil/util.hh
+++ b/src/libutil/util.hh
@@ -63,7 +63,7 @@ Path canonPath(const Path & path, bool resolveSymlinks = false);
 Path dirOf(const Path & path);
 
 /* Return the base name of the given canonical path, i.e., everything
-   following the final `/'. */
+   following the final `/' (trailing slashes are removed). */
 std::string_view baseNameOf(std::string_view path);
 
 /* Check whether 'path' is a descendant of 'dir'. */