use more meaningful errors

bow-swift · Jun 10, 2020 · fa2138c · fa2138c
1 parent 7ec7ee8
commit fa2138c
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Showing 2 changed files with 19 additions and 9 deletions.
diff --git a/nef/AppDelegate.swift b/nef/AppDelegate.swift
@@ -110,7 +110,7 @@ class AppDelegate: NSObject, NSApplicationDelegate {
 
         let config = ClipboardConfig(clipboard: .general, notificationCenter: .current())
 
-        assembler.resolveCarbon(code: code).env()^
+        assembler.resolveCarbon(code: code).env()^.mapError { _ in .carbon }
             .flatMap(pasteboardCarbonIO)^
             .provide(config)
             .unsafeRunAsync(on: .global(qos: .userInitiated)) { output in

diff --git a/nef/Extensions/AppDelegate+Notifications.swift b/nef/Extensions/AppDelegate+Notifications.swift
@@ -11,12 +11,12 @@ struct ClipboardConfig {
 }
 
 extension AppDelegate {
-    func pasteboardCarbonIO(data: Data) -> EnvIO<ClipboardConfig, AppDelegate.Error, NSImage> {
-        func makeImage(_ data: Data) -> IO<AppDelegate.Error, NSImage> {
-            data.makeImage().mapError { _ in AppDelegate.Error.carbon }
+    func pasteboardCarbonIO(data: Data) -> EnvIO<ClipboardConfig, Clipboard.Error, NSImage> {
+        func makeImage(_ data: Data) -> IO<Clipboard.Error, NSImage> {
+            data.makeImage().mapError { _ in .invalidData }
         }
 
-        let image = EnvIO<ClipboardConfig, AppDelegate.Error, NSImage>.var()
+        let image = EnvIO<ClipboardConfig, Clipboard.Error, NSImage>.var()
 
         return binding(
             image <- makeImage(data).env(),
@@ -29,10 +29,12 @@ extension AppDelegate {
         yield:image.get)^
     }
 
-    private func writeToPasteboard(_ image: NSImage) -> EnvIO<ClipboardConfig, AppDelegate.Error, Void> {
+    private func writeToPasteboard(_ image: NSImage) -> EnvIO<ClipboardConfig, Clipboard.Error, Void> {
         EnvIO.invoke { config in
             config.clipboard.clearContents()
-            config.clipboard.writeObjects([image])
+            if !config.clipboard.writeObjects([image]) {
+                throw Clipboard.Error.writeToClipboard
+            }
         }^
     }
 }
@@ -50,13 +52,13 @@ extension AppDelegate: UNUserNotificationCenterDelegate {
         NefNotification.center.requestAuthorization(options: [.alert, .sound]) { granted, _  in }
     }
 
-    func removeOldNotifications() -> EnvIO<ClipboardConfig, AppDelegate.Error, Void> {
+    func removeOldNotifications() -> EnvIO<ClipboardConfig, Clipboard.Error, Void> {
         EnvIO.invoke { config in
             config.notificationCenter.removeAllDeliveredNotifications()
         }^
     }
 
-    func showNotification(title: String, body: String, imageData: Data? = nil, actions: [NefNotification.Action] = [], id: String = UUID().uuidString) -> EnvIO<ClipboardConfig,AppDelegate.Error, Void> {
+    func showNotification(title: String, body: String, imageData: Data? = nil, actions: [NefNotification.Action] = [], id: String = UUID().uuidString) -> EnvIO<ClipboardConfig, Clipboard.Error, Void> {
         EnvIO.invoke { config in
             let content = UNMutableNotificationContent()
             content.title = title
@@ -111,6 +113,14 @@ enum NefNotification {
     static var center: UNUserNotificationCenter { .current() }
 }
 
+enum Clipboard {
+    enum Error: Swift.Error {
+        case invalidData
+        case writeToClipboard
+        case carbon
+    }
+}
+
 extension NefNotification {
     enum Action: Equatable {
         case saveImage