1 files changed, 63 insertions, 0 deletions
diff --git a/Userland/Libraries/LibJS/Tests/string-escapes.js b/Userland/Libraries/LibJS/Tests/string-escapes.js
new file mode 100644
index 0000000000..8a0920361e
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/string-escapes.js
@@ -0,0 +1,63 @@
+test("hex escapes", () => {
+    expect("\x55").toBe("U");
+    expect("X55").toBe("X55");
+    expect(`\x55`).toBe("U");
+    expect(`\X55`).toBe("X55");
+    expect("\xff").toBe(String.fromCharCode(0xff));
+    expect("'\\x'").not.toEval();
+    expect("'\\x1'").not.toEval();
+    expect("'\\xz'").not.toEval();
+    expect("'\\xzz'").not.toEval();
+    expect("'\\x🐞'").not.toEval();
+});
+
+test("unicode escapes", () => {
+    expect("\u26a0").toBe("⚠");
+    expect(`\u26a0`).toBe("⚠");
+    expect("\u{1f41e}").toBe("🐞");
+    expect(`\u{1f41e}`).toBe("🐞");
+    expect("\u00ff").toBe(String.fromCharCode(0xff));
+    expect("'\\u'").not.toEval();
+    expect("'\\u1'").not.toEval();
+    expect("'\\uf'").not.toEval();
+    expect("'\\u123'").not.toEval();
+    expect("'\\u123z'").not.toEval();
+    expect("'\\uz'").not.toEval();
+    expect("'\\uzz'").not.toEval();
+    expect("'\\uzzzz'").not.toEval();
+    expect("'\\u{'").not.toEval();
+    expect("'\\u{}'").not.toEval();
+    expect("'\\u{z}'").not.toEval();
+    expect("'\\u🐞'").not.toEval();
+});
+
+describe("octal escapes", () => {
+    test("basic functionality", () => {
+        expect("\1").toBe("\u0001");
+        expect("\2").toBe("\u0002");
+        expect("\3").toBe("\u0003");
+        expect("\4").toBe("\u0004");
+        expect("\5").toBe("\u0005");
+        expect("\6").toBe("\u0006");
+        expect("\7").toBe("\u0007");
+        // prettier-ignore
+        expect("\8").toBe("8");
+        // prettier-ignore
+        expect("\9").toBe("9");
+        expect("\128").toBe("\n8");
+        expect("\141bc").toBe("abc");
+        expect("f\157o\142a\162").toBe("foobar");
+        expect("\123\145\162\145\156\151\164\171\117\123").toBe("SerenityOS");
+    });
+
+    test("syntax error in template literal", () => {
+        expect("`\\123`").not.toEval();
+    });
+
+    test("syntax error in strict mode", () => {
+        expect("'use strict'; '\\123'").not.toEval();
+        expect('"use strict"; "\\123"').not.toEval();
+        // Special case, string literal precedes use strict directive
+        expect("'\\123'; somethingElse; 'use strict'").not.toEval();
+    });
+});