Add ArrayBuffer, JSTypedArray, and Data conversion (#13)

Resolves #7.

Author: MaxDesiatov

Sources/DOMKit/ECMAScript/ArrayBuffer.swift

@@ -2,8 +2,8 @@
 //  Created by Manuel Burghard. Licensed unter MIT.
 //
 
-import JavaScriptKit
 import _CJavaScriptKit
+import JavaScriptKit
 
 public typealias Int8Array = JSTypedArray<Int8>
 public typealias Int16Array = JSTypedArray<Int16>
@@ -15,7 +15,6 @@ public typealias Float32Array = JSTypedArray<Float32>
 public typealias Float64Array = JSTypedArray<Float64>
 
 public class ArrayBuffer: JSBridgedClass {
-
     public class var constructor: JSFunction { JSObject.global.ArrayBuffer.function! }
 
     public let jsObject: JSObject
@@ -25,10 +24,32 @@ public class ArrayBuffer: JSBridgedClass {
     }
 
     public convenience init(length: Int) {
-        self.init(unsafelyWrapping: Self.constructor.new( length))
+        self.init(unsafelyWrapping: Self.constructor.new(length))
     }
 
     public static func isView(_ object: JSValueCompatible) -> Bool {
         JSObject.global.ArrayBuffer.object!.isView!(object).fromJSValue()!
     }
 }
+
+public extension JSTypedArray {
+    convenience init(_ arrayBuffer: ArrayBuffer) {
+        self.init(unsafelyWrapping: Self.constructor.new(arrayBuffer))
+    }
+
+    var buffer: ArrayBuffer {
+        ArrayBuffer(unsafelyWrapping: jsObject.buffer.object!)
+    }
+}
+
+#if canImport(Foundation)
+import Foundation
+
+public extension Data {
+    init(_ arrayBuffer: ArrayBuffer) {
+        self = JSTypedArray<UInt8>(arrayBuffer).withUnsafeBytes {
+            Data(buffer: $0)
+        }
+    }
+}
+#endif

Tests/DOMKitTests/DOMKitTests.swift

@@ -1,8 +1,10 @@
-import XCTest
 import DOMKit
+import Foundation
+import JavaScriptKit
+import XCTest
 
 final class DOMKitTests: XCTestCase {
-    func testExample() {
+    func testQuerySelector() {
         let document = globalThis.document
         let button = document.createElement(localName: "button")
         button.textContent = "Hello, world!"
@@ -11,4 +13,31 @@ final class DOMKitTests: XCTestCase {
         let queriedButton = document.querySelector(selectors: "body button")
         XCTAssertEqual(queriedButton?.textContent, "Hello, world!")
     }
+
+    func testDataToTypedArray() {
+        let array: [UInt8] = [1, 2, 3, 4, 5]
+        let data = Data(array)
+        let typedArray = JSTypedArray(data)
+
+        typedArray.withUnsafeBytes {
+            XCTAssertEqual($0.count, data.count)
+            for index in $0.indices {
+                XCTAssertEqual(array[index], $0[index])
+            }
+        }
+    }
+
+    func testTypedArrayToData() {
+        let array: [UInt8] = [1, 2, 3, 4, 5]
+        let typedArray = JSTypedArray(array)
+
+        let data = Data(typedArray.buffer)
+
+        typedArray.withUnsafeBytes {
+            XCTAssertEqual($0.count, data.count)
+            for index in $0.indices {
+                XCTAssertEqual(array[index], $0[index])
+            }
+        }
+    }
 }