add test and update bridge - msg not required

Sources/ShopifyCheckout/CheckoutBridge.swift

@@ -56,7 +56,7 @@ extension CheckoutBridge {
 	enum WebEvent: Decodable {
 		case checkoutComplete
 		case checkoutCanceled
-		case checkoutNotAvailable(String)
+		case checkoutNotAvailable
 		case unsupported(String)
 
 		enum CodingKeys: String, CodingKey {
@@ -74,8 +74,8 @@ extension CheckoutBridge {
 				self = .checkoutComplete
 			case "close":
 				self = .checkoutCanceled
-			case "checkout_not_available":
-				self = .checkoutNotAvailable(name)
+			case "checkoutNotAvailable":
+				self = .checkoutNotAvailable
 			default:
 				self = .unsupported(name)
 			}

Sources/ShopifyCheckout/CheckoutView.swift

@@ -101,9 +101,9 @@ extension CheckoutView: WKScriptMessageHandler {
 			case .checkoutComplete:
 				CheckoutView.cache = nil
 				viewDelegate?.checkoutViewDidCompleteCheckout()
-			case .checkoutNotAvailable(let message):
+			case .checkoutNotAvailable:
 				CheckoutView.cache = nil
-				viewDelegate?.checkoutViewDidFailWithError(error: .checkoutNotAvailable(message: message))
+				viewDelegate?.checkoutViewDidFailWithError(error: .checkoutNotAvailable(message: "Checkout not available."))
 			default: break
 			}
 		} catch {

Tests/ShopifyCheckoutTests/CheckoutBridgeTests.swift

@@ -97,4 +97,18 @@ class CheckoutBridgeTests: XCTestCase {
 			return XCTFail("expected CheckoutScriptMessage.checkoutComplete, got \(result)")
 		}
 	}
+
+	func testDecodeSupportsCheckoutNotAvailableEvent() throws {
+		let mock = WKScriptMessageMock(body: """
+		{
+			"name": "checkoutNotAvailable"
+		}
+		""")
+
+		let result = try CheckoutBridge.decode(mock)
+
+		guard case CheckoutBridge.WebEvent.checkoutNotAvailable = result else {
+			return XCTFail("expected CheckoutScriptMessage.checkoutNotAvailable, got \(result)")
+		}
+	}
 }