Improved error handling

Author: insidegui

PACore/Source/PAInvocation.swift

@@ -8,6 +8,17 @@
 
 import Foundation
 
+public enum PAInvocationError: Error {
+    case invalidData
+    
+    public var localizedDescription: String {
+        switch self {
+        case .invalidData:
+            return NSLocalizedString("Unable to process selection data", comment: "Unable to process selection data (error message)")
+        }
+    }
+}
+
 public final class PAInvocation {
 
     public enum Platform: String {
@@ -46,7 +57,7 @@ public final class PAInvocation {
         }
     }
 
-    public class func invoke(with buffer: String, platform: Platform = .iOS) {
+    public class func invoke(with buffer: String, platform: Platform = .iOS) throws {
         let info = [
             Keys.buffer: buffer,
             Keys.platform: platform.rawValue.lowercased()
@@ -58,7 +69,7 @@ public final class PAInvocation {
                 DistributedNotificationCenter.default().post(name: Notifications.CreatePlayground, object: json, userInfo: nil)
             }
         } catch {
-            
+            throw PAInvocationError.invalidData
         }
     }
 

PlayAwaysExtension/Commands.swift

@@ -10,10 +10,22 @@ import Foundation
 import XcodeKit
 import PACore
 
+final class Commander {
+    
+    class func perform(with invocation: XCSourceEditorCommandInvocation, for platform: PAInvocation.Platform) {
+        do {
+            try PAInvocation.invoke(with: invocation.buffer.completeBuffer, platform: platform)
+        } catch {
+            NSAlert(error: error).runModal()
+        }
+    }
+    
+}
+
 class EmbeddedCommand: NSObject, XCSourceEditorCommand {
 
     func perform(with invocation: XCSourceEditorCommandInvocation, completionHandler: @escaping (Error?) -> Void ) -> Void {
-        PAInvocation.invoke(with: invocation.buffer.completeBuffer, platform: .iOS)
+        Commander.perform(with: invocation, for: .iOS)
 
         completionHandler(nil)
     }
@@ -23,7 +35,7 @@ class EmbeddedCommand: NSObject, XCSourceEditorCommand {
 class MacCommand: NSObject, XCSourceEditorCommand {
 
     func perform(with invocation: XCSourceEditorCommandInvocation, completionHandler: @escaping (Error?) -> Void ) -> Void {
-        PAInvocation.invoke(with: invocation.buffer.completeBuffer, platform: .macOS)
+        Commander.perform(with: invocation, for: .macOS)
 
         completionHandler(nil)
     }
@@ -33,7 +45,7 @@ class MacCommand: NSObject, XCSourceEditorCommand {
 class TVCommand: NSObject, XCSourceEditorCommand {
 
     func perform(with invocation: XCSourceEditorCommandInvocation, completionHandler: @escaping (Error?) -> Void ) -> Void {
-        PAInvocation.invoke(with: invocation.buffer.completeBuffer, platform: .tvOS)
+        Commander.perform(with: invocation, for: .tvOS)
 
         completionHandler(nil)
     }