1 files changed, 31 insertions, 0 deletions
diff --git a/fs/utils_test.ts b/fs/utils_test.ts
new file mode 100644
index 000000000..9d6959de5
--- /dev/null
+++ b/fs/utils_test.ts
@@ -0,0 +1,31 @@
+// Copyright the Browserify authors. MIT License.
+
+import { test } from "../testing/mod.ts";
+import { assertEquals } from "../testing/asserts.ts";
+import { isSubdir } from "./utils.ts";
+import * as path from "./path/mod.ts";
+
+test(function _isSubdir() {
+  const pairs = [
+    ["", "", false, path.posix.sep],
+    ["/first/second", "/first", false, path.posix.sep],
+    ["/first", "/first", false, path.posix.sep],
+    ["/first", "/first/second", true, path.posix.sep],
+    ["first", "first/second", true, path.posix.sep],
+    ["../first", "../first/second", true, path.posix.sep],
+    ["c:\\first", "c:\\first", false, path.win32.sep],
+    ["c:\\first", "c:\\first\\second", true, path.win32.sep]
+  ];
+
+  pairs.forEach(function(p) {
+    const src = p[0] as string;
+    const dest = p[1] as string;
+    const expected = p[2] as boolean;
+    const sep = p[3] as string;
+    assertEquals(
+      isSubdir(src, dest, sep),
+      expected,
+      `'${src}' should ${expected ? "" : "not"} be parent dir of '${dest}'`
+    );
+  });
+});