1 files changed, 78 insertions, 0 deletions
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Number/Number.prototype.toLocaleString.js b/Userland/Libraries/LibJS/Tests/builtins/Number/Number.prototype.toLocaleString.js
new file mode 100644
index 0000000000..72ffb24573
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/builtins/Number/Number.prototype.toLocaleString.js
@@ -0,0 +1,78 @@
+describe("errors", () => {
+    test("must be called with numeric |this|", () => {
+        [true, [], {}, Symbol("foo"), "bar", 1n].forEach(value => {
+            expect(() => Number.prototype.toLocaleString.call(value)).toThrowWithMessage(
+                TypeError,
+                "Not an object of type Number"
+            );
+        });
+    });
+});
+
+describe("correct behavior", () => {
+    test("length", () => {
+        expect(Number.prototype.toLocaleString).toHaveLength(0);
+    });
+});
+
+describe("special values", () => {
+    test("NaN", () => {
+        expect(NaN.toLocaleString()).toBe("NaN");
+        expect(NaN.toLocaleString("en")).toBe("NaN");
+        expect(NaN.toLocaleString("ar")).toBe("ليس رقم");
+    });
+
+    test("Infinity", () => {
+        expect(Infinity.toLocaleString()).toBe("∞");
+        expect(Infinity.toLocaleString("en")).toBe("∞");
+        expect(Infinity.toLocaleString("ar")).toBe("∞");
+    });
+});
+
+describe("styles", () => {
+    test("decimal", () => {
+        expect((12).toLocaleString("en")).toBe("12");
+        expect((12).toLocaleString("ar")).toBe("\u0661\u0662");
+    });
+
+    test("percent", () => {
+        expect((0.234).toLocaleString("en", { style: "percent" })).toBe("23%");
+        expect((0.234).toLocaleString("ar", { style: "percent" })).toBe("\u0662\u0663\u066a\u061c");
+    });
+
+    test("currency", () => {
+        expect(
+            (1.23).toLocaleString("en", {
+                style: "currency",
+                currency: "USD",
+                currencyDisplay: "name",
+            })
+        ).toBe("1.23 US dollars");
+
+        expect(
+            (1.23).toLocaleString("ar", {
+                style: "currency",
+                currency: "USD",
+                currencyDisplay: "name",
+            })
+        ).toBe("\u0661\u066b\u0662\u0663 دولار أمريكي");
+    });
+
+    test("unit", () => {
+        expect(
+            (1.23).toLocaleString("en", {
+                style: "unit",
+                unit: "kilometer-per-hour",
+                unitDisplay: "long",
+            })
+        ).toBe("1.23 kilometers per hour");
+
+        expect(
+            (1.23).toLocaleString("ar", {
+                style: "unit",
+                unit: "kilometer-per-hour",
+                unitDisplay: "long",
+            })
+        ).toBe("\u0661\u066b\u0662\u0663 كيلومتر في الساعة");
+    });
+});