Rename MarkAllReadCommand to MarkReadOrUnreadCommand and make it handle both cases.

Commands/MarkAllReadCommand.swift

@@ -1,54 +0,0 @@
-//
-//  MarkAllReadCommand.swift
-//  Evergreen
-//
-//  Created by Brent Simmons on 10/26/17.
-//  Copyright © 2017 Ranchero Software. All rights reserved.
-//
-
-import Foundation
-import RSCore
-import Data
-
-final class MarkAllReadCommand: UndoableCommand {
-    
-    static private let actionName = NSLocalizedString("Mark All as Read", comment: "command")
-    let undoActionName = actionName
-    let redoActionName = actionName
-    let articles: Set<Article>
-	let undoManager: UndoManager
-    
-	init?(initialArticles: [Article], undoManager: UndoManager) {
-        
-        // Filter out articles already read.
-        let unreadArticles = initialArticles.filter { !$0.status.read }
-		if unreadArticles.isEmpty {
-			return nil
-		}
-
-        self.articles = Set(unreadArticles)
-		self.undoManager = undoManager
-    }
-    
-    func perform() {
-        mark(read: true)
-		registerUndo()
-    }
-    
-    func undo() {
-        mark(read: false)
-		registerRedo()
-    }
-    
-    func redo() {
-        perform()
-    }
-}
-
-private extension MarkAllReadCommand {
-    
-    func mark(read: Bool) {
-        
-        markArticles(articles, statusKey: .read, flag: read)
-    }
-}

Commands/MarkReadOrUnreadCommand.swift

@@ -0,0 +1,63 @@
+//
+//  MarkReadOrUnreadCommand.swift
+//  Evergreen
+//
+//  Created by Brent Simmons on 10/26/17.
+//  Copyright © 2017 Ranchero Software. All rights reserved.
+//
+
+import Foundation
+import RSCore
+import Data
+
+final class MarkReadOrUnreadCommand: UndoableCommand {
+    
+	static private let markReadActionName = NSLocalizedString("Mark Read", comment: "command")
+	static private let markUnreadActionName = NSLocalizedString("Mark Unread", comment: "command")
+	let undoActionName: String
+	let redoActionName: String
+    let articles: Set<Article>
+	let undoManager: UndoManager
+	let markingRead: Bool
+
+	init?(initialArticles: [Article], markingRead: Bool, undoManager: UndoManager) {
+        
+        // Filter out articles already read.
+		let articlesToMark = initialArticles.filter { markingRead ? !$0.status.read : $0.status.read }
+		if articlesToMark.isEmpty {
+			return nil
+		}
+		self.articles = Set(articlesToMark)
+
+		self.markingRead = markingRead
+
+ 		self.undoManager = undoManager
+
+		if markingRead {
+			self.undoActionName = MarkReadOrUnreadCommand.markReadActionName
+			self.redoActionName = MarkReadOrUnreadCommand.markReadActionName
+		}
+		else {
+			self.undoActionName = MarkReadOrUnreadCommand.markUnreadActionName
+			self.redoActionName = MarkReadOrUnreadCommand.markUnreadActionName
+		}
+    }
+    
+    func perform() {
+        mark(read: markingRead)
+		registerUndo()
+    }
+    
+    func undo() {
+        mark(read: !markingRead)
+		registerRedo()
+    }
+}
+
+private extension MarkReadOrUnreadCommand {
+    
+    func mark(read: Bool) {
+        
+        markArticles(articles, statusKey: .read, flag: read)
+    }
+}

Evergreen.xcodeproj/project.pbxproj

@@ -17,7 +17,7 @@
 		846E773E1F6EF67A00A165E2 /* Account.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 846E773A1F6EF5D700A165E2 /* Account.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		846E77411F6EF6A100A165E2 /* Database.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 846E77211F6EF5D100A165E2 /* Database.framework */; };
 		846E77421F6EF6A100A165E2 /* Database.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 846E77211F6EF5D100A165E2 /* Database.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
-		84702AA41FA27AC0006B8943 /* MarkAllReadCommand.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84702AA31FA27AC0006B8943 /* MarkAllReadCommand.swift */; };
+		84702AA41FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84702AA31FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift */; };
 		849A97431ED9EAA9007D329B /* AddFolderWindowController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 849A97421ED9EAA9007D329B /* AddFolderWindowController.swift */; };
 		849A97531ED9EAC0007D329B /* AddFeedController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 849A97511ED9EAC0007D329B /* AddFeedController.swift */; };
 		849A97541ED9EAC0007D329B /* AddFeedWindowController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 849A97521ED9EAC0007D329B /* AddFeedWindowController.swift */; };
@@ -383,7 +383,7 @@
 		846A7BEB1F872C5600FEFD30 /* BatchUpdate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = BatchUpdate.swift; path = Evergreen/BatchUpdate.swift; sourceTree = "<group>"; };
 		846E77161F6EF5D000A165E2 /* Database.xcodeproj */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.pb-project"; name = Database.xcodeproj; path = Frameworks/Database/Database.xcodeproj; sourceTree = "<group>"; };
 		846E77301F6EF5D600A165E2 /* Account.xcodeproj */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.pb-project"; name = Account.xcodeproj; path = Frameworks/Account/Account.xcodeproj; sourceTree = "<group>"; };
-		84702AA31FA27AC0006B8943 /* MarkAllReadCommand.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MarkAllReadCommand.swift; sourceTree = "<group>"; };
+		84702AA31FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MarkReadOrUnreadCommand.swift; sourceTree = "<group>"; };
 		849A97421ED9EAA9007D329B /* AddFolderWindowController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AddFolderWindowController.swift; sourceTree = "<group>"; };
 		849A97511ED9EAC0007D329B /* AddFeedController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = AddFeedController.swift; path = AddFeed/AddFeedController.swift; sourceTree = "<group>"; };
 		849A97521ED9EAC0007D329B /* AddFeedWindowController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = AddFeedWindowController.swift; path = AddFeed/AddFeedWindowController.swift; sourceTree = "<group>"; };
@@ -525,7 +525,7 @@
 		84702AB31FA27AE8006B8943 /* Commands */ = {
 			isa = PBXGroup;
 			children = (
-				84702AA31FA27AC0006B8943 /* MarkAllReadCommand.swift */,
+				84702AA31FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift */,
 			);
 			path = Commands;
 			sourceTree = "<group>";
@@ -1185,7 +1185,7 @@
 				842E45E51ED8C6B7000A8B52 /* MainWindowSplitView.swift in Sources */,
 				849A97661ED9EB96007D329B /* SidebarViewController.swift in Sources */,
 				849A97641ED9EB96007D329B /* SidebarOutlineView.swift in Sources */,
-				84702AA41FA27AC0006B8943 /* MarkAllReadCommand.swift in Sources */,
+				84702AA41FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift in Sources */,
 				849A979F1ED9F130007D329B /* SidebarCell.swift in Sources */,
 				849A97651ED9EB96007D329B /* SidebarTreeControllerDelegate.swift in Sources */,
 				849A97671ED9EB96007D329B /* UnreadCountView.swift in Sources */,

Evergreen/MainWindow/Timeline/TimelineViewController.swift

@@ -123,10 +123,10 @@ class TimelineViewController: NSViewController, NSTableViewDelegate, NSTableView
 	
 	func markAllAsRead() {
 
-		guard let undoManager = undoManager, let markAllReadCommand = MarkAllReadCommand(initialArticles: articles, undoManager: undoManager) else {
+		guard let undoManager = undoManager, let markReadCommand = MarkReadOrUnreadCommand(initialArticles: articles, markingRead: true, undoManager: undoManager) else {
 			return
 		}
-		runCommand(markAllReadCommand)
+		runCommand(markReadCommand)
 	}
 
 	// MARK: - Undoable Commands
@@ -144,9 +144,9 @@ class TimelineViewController: NSViewController, NSTableViewDelegate, NSTableView
 
 	private func clearUndoableCommands() {
 
-		// When the timeline is reloaded based on a different sidebar selection,
+		// When the timeline is reloaded and the list of articles changes,
 		// undoable commands should be dropped — otherwise things like
-		// Redo Mark All as Read are ambiguous. (Do they apply to the previous articles
+		// Redo Mark Read are ambiguous. (Do they apply to the previous articles
 		// or to the current articles?)
 
 		guard let undoManager = undoManager else {
@@ -174,17 +174,28 @@ class TimelineViewController: NSViewController, NSTableViewDelegate, NSTableView
 		let status = articles.first!.status
 		let markAsRead = !status.read
 
-		markArticles(Set(articles), statusKey: .read, flag: markAsRead)
+		if markAsRead {
+			markSelectedArticlesAsRead(sender)
+		}
+		else {
+			markSelectedArticlesAsUnread(sender)
+		}
 	}
 	
 	@IBAction func markSelectedArticlesAsRead(_ sender: AnyObject) {
 
-		markArticles(Set(selectedArticles), statusKey: .read, flag: true)
+		guard let undoManager = undoManager, let markReadCommand = MarkReadOrUnreadCommand(initialArticles: selectedArticles, markingRead: true, undoManager: undoManager) else {
+			return
+		}
+		runCommand(markReadCommand)
 	}
 	
 	@IBAction func markSelectedArticlesAsUnread(_ sender: AnyObject) {
 		
-		markArticles(Set(selectedArticles), statusKey: .read, flag: false)
+		guard let undoManager = undoManager, let markUnreadCommand = MarkReadOrUnreadCommand(initialArticles: selectedArticles, markingRead: false, undoManager: undoManager) else {
+			return
+		}
+		runCommand(markUnreadCommand)
 	}
 	
 	// MARK: - Navigation

Frameworks/RSCore/RSCore/UndoableCommand.swift

@@ -14,9 +14,8 @@ public protocol UndoableCommand: class {
 	var redoActionName: String { get }
 	var undoManager: UndoManager { get }
 
-	func perform()
+	func perform() // must call registerUndo()
-	func undo()
+	func undo() // must call registerRedo()
-	func redo()
 }
 
 extension UndoableCommand {
@@ -33,7 +32,7 @@ extension UndoableCommand {
 		
 		undoManager.setActionName(redoActionName)
 		undoManager.registerUndo(withTarget: self) { (target) in
-			self.redo()
+			self.perform()
 		}
 	}
 }