LibJS: Implement stringification Temporal.PlainDate prototypes

Author: https://github.com/trflynn89
Commit: 9fbb5a57fa
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2513
Reviewed-by: https://github.com/shannonbooth ✅

Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.prototype.toJSON.js

@@ -0,0 +1,23 @@
+describe("correct behavior", () => {
+    test("length is 0", () => {
+        expect(Temporal.PlainDate.prototype.toJSON).toHaveLength(0);
+    });
+
+    test("basic functionality", () => {
+        let plainDate;
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6);
+        expect(plainDate.toJSON()).toBe("2021-07-06");
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6, "gregory");
+        expect(plainDate.toJSON()).toBe("2021-07-06[u-ca=gregory]");
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a Temporal.PlainDate object", () => {
+        expect(() => {
+            Temporal.PlainDate.prototype.toJSON.call("foo");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.PlainDate");
+    });
+});

Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.prototype.toLocaleString.js

@@ -0,0 +1,23 @@
+describe("correct behavior", () => {
+    test("length is 0", () => {
+        expect(Temporal.PlainDate.prototype.toLocaleString).toHaveLength(0);
+    });
+
+    test("basic functionality", () => {
+        let plainDate;
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6);
+        expect(plainDate.toLocaleString()).toBe("2021-07-06");
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6, "gregory");
+        expect(plainDate.toLocaleString()).toBe("2021-07-06[u-ca=gregory]");
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a Temporal.PlainDate object", () => {
+        expect(() => {
+            Temporal.PlainDate.prototype.toLocaleString.call("foo");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.PlainDate");
+    });
+});

Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.prototype.toString.js

@@ -0,0 +1,56 @@
+describe("correct behavior", () => {
+    test("length is 0", () => {
+        expect(Temporal.PlainDate.prototype.toString).toHaveLength(0);
+    });
+
+    test("basic functionality", () => {
+        let plainDate;
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6);
+        expect(plainDate.toString()).toBe("2021-07-06");
+        expect(plainDate.toString({ calendarName: "auto" })).toBe("2021-07-06");
+        expect(plainDate.toString({ calendarName: "always" })).toBe("2021-07-06[u-ca=iso8601]");
+        expect(plainDate.toString({ calendarName: "never" })).toBe("2021-07-06");
+        expect(plainDate.toString({ calendarName: "critical" })).toBe("2021-07-06[!u-ca=iso8601]");
+
+        plainDate = new Temporal.PlainDate(2021, 7, 6, "gregory");
+        expect(plainDate.toString()).toBe("2021-07-06[u-ca=gregory]");
+        expect(plainDate.toString({ calendarName: "auto" })).toBe("2021-07-06[u-ca=gregory]");
+        expect(plainDate.toString({ calendarName: "always" })).toBe("2021-07-06[u-ca=gregory]");
+        expect(plainDate.toString({ calendarName: "never" })).toBe("2021-07-06");
+        expect(plainDate.toString({ calendarName: "critical" })).toBe("2021-07-06[!u-ca=gregory]");
+
+        plainDate = new Temporal.PlainDate(0, 1, 1);
+        expect(plainDate.toString()).toBe("0000-01-01");
+
+        plainDate = new Temporal.PlainDate(999, 1, 1);
+        expect(plainDate.toString()).toBe("0999-01-01");
+
+        plainDate = new Temporal.PlainDate(9999, 1, 1);
+        expect(plainDate.toString()).toBe("9999-01-01");
+
+        plainDate = new Temporal.PlainDate(12345, 1, 1);
+        expect(plainDate.toString()).toBe("+012345-01-01");
+
+        plainDate = new Temporal.PlainDate(123456, 1, 1);
+        expect(plainDate.toString()).toBe("+123456-01-01");
+
+        plainDate = new Temporal.PlainDate(-12345, 1, 1);
+        expect(plainDate.toString()).toBe("-012345-01-01");
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a Temporal.PlainDate object", () => {
+        expect(() => {
+            Temporal.PlainDate.prototype.toString.call("foo");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.PlainDate");
+    });
+
+    test("calendarName option must be one of 'auto', 'always', 'never', 'critical'", () => {
+        const plainDate = new Temporal.PlainDate(2021, 7, 6);
+        expect(() => {
+            plainDate.toString({ calendarName: "foo" });
+        }).toThrowWithMessage(RangeError, "foo is not a valid value for option calendarName");
+    });
+});