Add JSDate implementation with tests

IntegrationTests/TestSuites/Sources/PrimaryTests/main.swift

@@ -394,3 +394,27 @@ try test("TypedArray_Mutation") {
     }
     try expectEqual(toString(array.jsValue().object!), jsStringify(Array(0..<100)))
 }
+
+try test("Date") {
+    let date1Milliseconds = JSDate.now()
+    let date1 = JSDate(millisecondsSinceEpoch: date1Milliseconds)
+    let date2 = JSDate(millisecondsSinceEpoch: date1.valueOf())
+
+    try expectEqual(date1.valueOf(), date2.valueOf())
+    try expectEqual(date1.fullYear, date2.fullYear)
+    try expectEqual(date1.month, date2.month)
+    try expectEqual(date1.date, date2.date)
+    try expectEqual(date1.day, date2.day)
+    try expectEqual(date1.hours, date2.hours)
+    try expectEqual(date1.minutes, date2.minutes)
+    try expectEqual(date1.seconds, date2.seconds)
+    try expectEqual(date1.milliseconds, date2.milliseconds)
+    try expectEqual(date1.utcFullYear, date2.utcFullYear)
+    try expectEqual(date1.utcMonth, date2.utcMonth)
+    try expectEqual(date1.utcDate, date2.utcDate)
+    try expectEqual(date1.utcDay, date2.utcDay)
+    try expectEqual(date1.utcHours, date2.utcHours)
+    try expectEqual(date1.utcMinutes, date2.utcMinutes)
+    try expectEqual(date1.utcSeconds, date2.utcSeconds)
+    try expectEqual(date1.utcMilliseconds, date2.utcMilliseconds)
+}

Sources/JavaScriptKit/BasicObjects/JSDate.swift

@@ -0,0 +1,210 @@
+public final class JSDate {
+    private static let constructor = JSObject.global.Date.function!
+    public let ref: JSObject
+
+    public init(millisecondsSinceEpoch: Double? = nil) {
+        if let milliseconds = millisecondsSinceEpoch {
+            ref = Self.constructor.new(milliseconds)
+        } else {
+            ref = Self.constructor.new()
+        }
+    }
+
+    /** According to the standard, `monthIndex` is zero-indexed, where `11` is December. `day` 
+    represents a day of the month starting at `1`.
+    */
+    public init(
+        year: Int,
+        monthIndex: Int,
+        day: Int = 1,
+        hours: Int = 0,
+        minutes: Int = 0,
+        seconds: Int = 0,
+        milliseconds: Int = 0
+    ) {
+        ref = Self.constructor.new(year, monthIndex, day, hours, minutes, seconds, milliseconds)
+    }
+
+    /// Year of this date in local time zone.
+    public var fullYear: Int {
+        get {
+            Int(ref.getFullYear!().number!)
+        }
+        set {
+            _ = ref.setFullYear!(newValue)
+        }
+    }
+
+    /// Month of this date in `0–11` range in local time zone
+    public var month: Int {
+        get {
+            Int(ref.getMonth!().number!)
+        }
+        set {
+            _ = ref.setMonth!(newValue)
+        }
+    }
+
+    /// The day of the month in `1..31` range in local time zone.
+    public var date: Int {
+        get {
+            Int(ref.getDate!().number!)
+        }
+        set {
+            _ = ref.setDate!(newValue)
+        }
+    }
+
+    /// The day of the week in `0..6` range in local time zone.
+    public var day: Int {
+        Int(ref.getDay!().number!)
+    }
+
+    /// The amount of hours in this day from `0..23` range in local time zone.
+    public var hours: Int {
+        get {
+            Int(ref.getHours!().number!)
+        }
+        set {
+            _ = ref.setHours!(newValue)
+        }
+    }
+
+    /// The amount of minutes in this hours from `0..59` range in local time zone.
+    public var minutes: Int {
+        get {
+            Int(ref.getMinutes!().number!)
+        }
+        set {
+            _ = ref.setMinutes!(newValue)
+        }
+    }
+
+    /// The amount of seconds in this minute from `0..59` range in local time zone.
+    public var seconds: Int {
+        get {
+            Int(ref.getSeconds!().number!)
+        }
+        set {
+            _ = ref.setSeconds!(newValue)
+        }
+    }
+
+    /// The amount of milliseconds in this second `0..999` range in local time zone.
+    public var milliseconds: Int {
+        get {
+            Int(ref.getMilliseconds!().number!)
+        }
+        set {
+            _ = ref.setMilliseconds!(newValue)
+        }
+    }
+
+    /// Year of this date in the UTC time zone
+    public var utcFullYear: Int {
+        get {
+            Int(ref.getFullYear!().number!)
+        }
+        set {
+            _ = ref.setFullYear!(newValue)
+        }
+    }
+
+    /// Month of this date in `0–11` range in the UTC time zone
+    public var utcMonth: Int {
+        get {
+            Int(ref.getMonth!().number!)
+        }
+        set {
+            _ = ref.setMonth!(newValue)
+        }
+    }
+
+    /// The day of the month in `1..31` range in the UTC time zone
+    public var utcDate: Int {
+        get {
+            Int(ref.getDate!().number!)
+        }
+        set {
+            _ = ref.setDate!(newValue)
+        }
+    }
+
+    /// The day of the week in `0..6` range in the UTC time zone
+    public var utcDay: Int {
+        Int(ref.getDay!().number!)
+    }
+
+    /// The amount of hours in this day from `0..23` range in the UTC time zone
+    public var utcHours: Int {
+        get {
+            Int(ref.getHours!().number!)
+        }
+        set {
+            _ = ref.setHours!(newValue)
+        }
+    }
+
+    /// The amount of minutes in this hours from `0..59` range in the UTC time zone
+    public var utcMinutes: Int {
+        get {
+            Int(ref.getMinutes!().number!)
+        }
+        set {
+            _ = ref.setMinutes!(newValue)
+        }
+    }
+
+    /// The amount of seconds in this minute from `0..59` range in the UTC time zone
+    public var utcSeconds: Int {
+        get {
+            Int(ref.getSeconds!().number!)
+        }
+        set {
+            _ = ref.setSeconds!(newValue)
+        }
+    }
+
+    /// The amount of milliseconds in this second `0..999` range in the UTC time zone
+    public var utcMilliseconds: Int {
+        get {
+            Int(ref.getMilliseconds!().number!)
+        }
+        set {
+            _ = ref.setMilliseconds!(newValue)
+        }
+    }
+
+    /// Offset in minutes between the local time zone and UTC
+    public var timezoneOffset: Int {
+        Int(ref.getTimezoneOffset!().number!)
+    }
+
+    public func toISOString() -> String {
+        ref.toISOString!().string!
+    }
+
+    public func toLocaleDateString() -> String {
+        ref.toLocaleDateString!().string!
+    }
+
+    public func toLocaleTimeString() -> String {
+        ref.toLocaleTimeString!().string!
+    }
+
+    public func toUTCString() -> String {
+        ref.toUTCString!().string!
+    }
+
+    /// Number of seconds since midnight 01 January 1970 UTC to the present moment ignoring leap 
+    /// seconds
+    public static func now() -> Double {
+        constructor.now!().number!
+    }
+
+    /// Number of seconds since midnight 01 January 1970 UTC to the present moment ignoring leap 
+    /// seconds
+    public func valueOf() -> Double {
+        ref.valueOf!().number!
+    }
+}