Delete SeekingFavicon, which wasn’t needed as a separate object. Save a little memory this way too.

Evergreen.xcodeproj/project.pbxproj

@@ -20,7 +20,6 @@
 		84513F901FAA63950023A1A9 /* FeedListControlsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84513F8F1FAA63950023A1A9 /* FeedListControlsView.swift */; };
 		845213231FCA5B11003B6E93 /* ImageDownloader.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845213221FCA5B10003B6E93 /* ImageDownloader.swift */; };
 		845A29091FC74B8E007B49E3 /* SingleFaviconDownloader.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845A29081FC74B8E007B49E3 /* SingleFaviconDownloader.swift */; };
-		845A291B1FC75AA6007B49E3 /* SeekingFavicon.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845A291A1FC75AA6007B49E3 /* SeekingFavicon.swift */; };
 		845A29221FC9251E007B49E3 /* SidebarCellLayout.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845A29211FC9251E007B49E3 /* SidebarCellLayout.swift */; };
 		845A29241FC9255E007B49E3 /* SidebarCellAppearance.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845A29231FC9255E007B49E3 /* SidebarCellAppearance.swift */; };
 		845EE7B11FC2366500854A1F /* StarredFeedDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 845EE7B01FC2366500854A1F /* StarredFeedDelegate.swift */; };
@@ -421,7 +420,6 @@
 		84513F8F1FAA63950023A1A9 /* FeedListControlsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedListControlsView.swift; sourceTree = "<group>"; };
 		845213221FCA5B10003B6E93 /* ImageDownloader.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ImageDownloader.swift; sourceTree = "<group>"; };
 		845A29081FC74B8E007B49E3 /* SingleFaviconDownloader.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SingleFaviconDownloader.swift; sourceTree = "<group>"; };
-		845A291A1FC75AA6007B49E3 /* SeekingFavicon.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SeekingFavicon.swift; sourceTree = "<group>"; };
 		845A29211FC9251E007B49E3 /* SidebarCellLayout.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SidebarCellLayout.swift; sourceTree = "<group>"; };
 		845A29231FC9255E007B49E3 /* SidebarCellAppearance.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SidebarCellAppearance.swift; sourceTree = "<group>"; };
 		845B14A51FC2299E0013CF92 /* README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };
@@ -637,7 +635,6 @@
 			children = (
 				848F6AE41FC29CFA002D422E /* FaviconDownloader.swift */,
 				845A29081FC74B8E007B49E3 /* SingleFaviconDownloader.swift */,
-				845A291A1FC75AA6007B49E3 /* SeekingFavicon.swift */,
 				84FF69B01FC3793300DC198E /* FaviconURLFinder.swift */,
 			);
 			name = Favicons;
@@ -1370,7 +1367,6 @@
 				84F2D5371FC22FCC00998D64 /* PseudoFeed.swift in Sources */,
 				845EE7C11FC2488C00854A1F /* SmartFeed.swift in Sources */,
 				84702AA41FA27AC0006B8943 /* MarkReadOrUnreadCommand.swift in Sources */,
-				845A291B1FC75AA6007B49E3 /* SeekingFavicon.swift in Sources */,
 				849A979F1ED9F130007D329B /* SidebarCell.swift in Sources */,
 				849A97651ED9EB96007D329B /* SidebarTreeControllerDelegate.swift in Sources */,
 				849A97671ED9EB96007D329B /* UnreadCountView.swift in Sources */,

Evergreen/Favicons/FaviconDownloader.swift

@@ -17,10 +17,11 @@ extension Notification.Name {
 
 final class FaviconDownloader {
 
-	private var seekingFaviconCache = [String: SeekingFavicon]() // homePageURL: SeekingFavicon
-	private var singleFaviconDownloaderCache = [String: SingleFaviconDownloader]() // faviconURL: SingleFaviconDownloader
 	private let folder: String
 	private let diskCache: BinaryDiskCache
+	private var singleFaviconDownloaderCache = [String: SingleFaviconDownloader]() // faviconURL: SingleFaviconDownloader
+	private var homePageToFaviconURLCache = [String: String]() //homePageURL: faviconURL
+	private var homePageURLsWithNoFaviconURL = Set<String>()
 	private let queue: DispatchQueue
 
 	struct UserInfoKey {
@@ -33,7 +34,6 @@ final class FaviconDownloader {
 		self.diskCache = BinaryDiskCache(folder: folder)
 		self.queue = DispatchQueue(label: "FaviconDownloader serial queue - \(folder)")
 
-		NotificationCenter.default.addObserver(self, selector: #selector(seekingFaviconDidSeek(_:)), name: .SeekingFaviconSeekDidComplete, object: nil)
 		NotificationCenter.default.addObserver(self, selector: #selector(didLoadFavicon(_:)), name: .DidLoadFavicon, object: nil)
 	}
 
@@ -61,22 +61,30 @@ final class FaviconDownloader {
 
 	func favicon(withHomePageURL homePageURL: String) -> NSImage? {
 
-		guard let seekingFavicon = seekingFavicon(with: normalizedHomePageURL(homePageURL)) else {
+		let url = normalizedHomePageURL(homePageURL)
+		if homePageURLsWithNoFaviconURL.contains(url) {
 			return nil
 		}
-		return favicon(withSeekingFavicon: seekingFavicon)
+		
+		if let faviconURL = homePageToFaviconURLCache[url] {
+			return favicon(with: faviconURL)
+		}
+
+		FaviconURLFinder.findFaviconURL(url) { (faviconURL) in
+			if let faviconURL = faviconURL {
+				self.homePageToFaviconURLCache[url] = faviconURL
+				let _ = self.favicon(with: faviconURL)
+			}
+			else {
+				self.homePageURLsWithNoFaviconURL.insert(url)
+			}
+		}
+
+		return nil
 	}
 
 	// MARK: - Notifications
 
-	@objc func seekingFaviconDidSeek(_ note: Notification) {
-
-		guard let seekingFavicon = note.object as? SeekingFavicon else {
-			return
-		}
-		favicon(withSeekingFavicon: seekingFavicon)
-	}
-
 	@objc func didLoadFavicon(_ note: Notification) {
 
 		guard let singleFaviconDownloader = note.object as? SingleFaviconDownloader else {
@@ -92,7 +100,31 @@ final class FaviconDownloader {
 
 private extension FaviconDownloader {
 
-	private static let localeForLowercasing = Locale(identifier: "en_US")
+	static let localeForLowercasing = Locale(identifier: "en_US")
+
+	func findFaviconURL(with homePageURL: String, _ completion: @escaping (String?) -> Void) {
+
+		guard let url = URL(string: homePageURL) else {
+			completion(nil)
+			return
+		}
+
+		FaviconURLFinder.findFaviconURL(homePageURL) { (faviconURL) in
+
+			if let faviconURL = faviconURL {
+				completion(faviconURL)
+				return
+			}
+
+			guard let scheme = url.scheme, let host = url.host else {
+				completion(nil)
+				return
+			}
+
+			let defaultFaviconURL = "\(scheme)://\(host)/favicon.ico".lowercased(with: FaviconDownloader.localeForLowercasing)
+			completion(defaultFaviconURL)
+		}
+	}
 
 	func normalizedHomePageURL(_ url: String) -> String {
 
@@ -112,15 +144,6 @@ private extension FaviconDownloader {
 		return url + "/"
 	}
 
-	@discardableResult
-	func favicon(withSeekingFavicon seekingFavicon: SeekingFavicon) -> NSImage? {
-
-		guard let faviconURL = seekingFavicon.faviconURL else {
-			return nil
-		}
-		return favicon(with: faviconURL)
-	}
-
 	func faviconDownloader(withURL faviconURL: String) -> SingleFaviconDownloader {
 
 		if let downloader = singleFaviconDownloaderCache[faviconURL] {
@@ -133,19 +156,6 @@ private extension FaviconDownloader {
 		return downloader
 	}
 
-	func seekingFavicon(with homePageURL: String) -> SeekingFavicon? {
-
-		if let seekingFavicon = seekingFaviconCache[homePageURL] {
-			return seekingFavicon
-		}
-
-		guard let seekingFavicon = SeekingFavicon(homePageURL: homePageURL) else {
-			return nil
-		}
-		seekingFaviconCache[homePageURL] = seekingFavicon
-		return seekingFavicon
-	}
-
 	func postFaviconDidBecomeAvailableNotification(_ faviconURL: String) {
 
 		let userInfo: [AnyHashable: Any] = [UserInfoKey.faviconURL: faviconURL]

Evergreen/Favicons/SeekingFavicon.swift

@@ -1,58 +0,0 @@
-//
-//  SeekingFavicon.swift
-//  Evergreen
-//
-//  Created by Brent Simmons on 11/23/17.
-//  Copyright © 2017 Ranchero Software. All rights reserved.
-//
-
-import Foundation
-
-extension Notification.Name {
-
-	static let SeekingFaviconSeekDidComplete = Notification.Name("SeekingFaviconSeekDidCompleteNotification")
-}
-
-final class SeekingFavicon {
-
-	// At first, when looking for a favicon, we only know the homePageURL.
-	// The faviconURL may be specified by metadata in the home page,
-	// or it might be at /favicon.ico,
-	// or it might not exist (or be unfindable, which is the same thing).
-
-	var didSeek = false
-	var faviconURL: String? {
-		return didSeek ? (foundFaviconURL ?? defaultFaviconURL) : nil
-	}
-
-	private let homePageURL: String
-	private var foundFaviconURL: String?
-	private let defaultFaviconURL: String // /favicon.ico
-	private static let localeForLowercasing = Locale(identifier: "en_US")
-
-	init?(homePageURL: String) {
-
-		guard let url = URL(string: homePageURL), let scheme = url.scheme, let host = url.host else {
-			return nil
-		}
-
-		self.homePageURL = homePageURL
-		self.defaultFaviconURL = "\(scheme)://\(host)/favicon.ico".lowercased(with: SeekingFavicon.localeForLowercasing)
-
-		findFaviconURL()
-	}
-}
-
-private extension SeekingFavicon {
-
-	func findFaviconURL() {
-
-		FaviconURLFinder.findFaviconURL(homePageURL) { (faviconURL) in
-
-			self.foundFaviconURL = faviconURL
-			self.didSeek = true
-
-			NotificationCenter.default.post(name: .SeekingFaviconSeekDidComplete, object: self)
-		}
-	}
-}