diff --git a/Libraries/LibJS/Tests/String.prototype.repeat.js b/Libraries/LibJS/Tests/String.prototype.repeat.js
new file mode 100644
index 0000000000..3b711a0f7b
--- /dev/null
+++ b/Libraries/LibJS/Tests/String.prototype.repeat.js
@@ -0,0 +1,37 @@
+load("test-common.js");
+
+try {
+    assert(String.prototype.repeat.length === 1);
+
+    try {
+        "foo".repeat(-1);
+        assertNotReached();
+    } catch (e) {
+        assert(e.name === "RangeError");
+        assert(e.message === "repeat count must be a positive number");
+    }
+
+    try {
+        "foo".repeat(Infinity);
+        assertNotReached();
+    } catch (e) {
+        assert(e.name === "RangeError");
+        assert(e.message === "repeat count must be a finite number");
+    }
+
+    assert("foo".repeat(0) === "");
+    assert("foo".repeat(1) === "foo");
+    assert("foo".repeat(2) === "foofoo");
+    assert("foo".repeat(3) === "foofoofoo");
+    assert("foo".repeat(3.1) === "foofoofoo");
+    assert("foo".repeat(3.5) === "foofoofoo");
+    assert("foo".repeat(3.9) === "foofoofoo");
+    assert("foo".repeat(null) === "");
+    assert("foo".repeat(undefined) === "");
+    assert("foo".repeat([]) === "");
+    assert("foo".repeat("") === "");
+
+    console.log("PASS");
+} catch (e) {
+    console.log("FAIL: " + e);
+}