Count line number with LineEndingScanner

CHANGELOG.md

@@ -8,6 +8,7 @@ Change Log
 ### Improvements
 
 - [beta] Update the help contents.
+- [beta][trivial] Optimize the performance of the Warnings pane.
 
 
 

CotEditor/Sources/IncompatibleCharacter.swift

@@ -31,7 +31,6 @@ struct IncompatibleCharacter: Equatable {
     let character: Character
     let convertedCharacter: String?
     let location: Int
-    let lineNumber: Int
     
     var range: NSRange  { NSRange(location: self.location, length: self.character.utf16.count) }
 }
@@ -73,8 +72,7 @@ extension String {
                 
                 return IncompatibleCharacter(character: character,
                                              convertedCharacter: converted,
-                                             location: location,
-                                             lineNumber: self.lineNumber(at: location))
+                                             location: location)
             }
     }
     
@@ -93,8 +91,7 @@ extension String {
                 
                 return IncompatibleCharacter(character: characters.0,
                                              convertedCharacter: String(characters.1),
-                                             location: location,
-                                             lineNumber: self.lineNumber(at: location))
+                                             location: location)
             }
     }
     

CotEditor/Sources/IncompatibleCharactersViewController.swift

@@ -250,7 +250,7 @@ extension IncompatibleCharactersViewController: NSTableViewDataSource {
         
         switch identifier {
             case .line:
-                return incompatibleCharacter.lineNumber
+                return self.document?.lineEndingScanner.lineNumber(at: incompatibleCharacter.location)
             case .character:
                 return String(incompatibleCharacter.character)
             case .converted:

CotEditor/Sources/InconsistentLineEndingsViewController.swift

@@ -148,7 +148,7 @@ extension InconsistentLineEndingsViewController: NSTableViewDataSource {
         switch identifier {
             case .line:
                 // calculate the line number first at this point to postpone the high cost processing as much as possible
-                return self.document?.string.lineNumber(at: lineEnding.location)
+                return self.document?.lineEndingScanner.lineNumber(at: lineEnding.location)
             case .lineEnding:
                 return lineEnding.item.name
             default:

CotEditor/Sources/LineEndingScanner.swift

@@ -29,13 +29,13 @@ import Combine
 
 final class LineEndingScanner {
     
-    @Published private(set) var inconsistentLineEndings: [ItemRange<LineEnding>] = []
+    @Published private(set) var inconsistentLineEndings: [ItemRange<LineEnding>]
     
     
     // MARK: Private Properties
     
     private let textStorage: NSTextStorage
-    private var lineEndings: [ItemRange<LineEnding>] = []
+    private var lineEndings: [ItemRange<LineEnding>]
     
     private var documentLineEnding: LineEnding  {
         
@@ -57,7 +57,8 @@ final class LineEndingScanner {
         self.textStorage = textStorage
         self.documentLineEnding = lineEnding
         
-        self.inconsistentLineEndings = self.scan()
+        self.lineEndings = textStorage.string.lineEndingRanges()
+        self.inconsistentLineEndings = self.lineEndings.filter { $0.item != lineEnding }
         
         self.storageObserver = NotificationCenter.default.publisher(for: NSTextStorage.didProcessEditingNotification, object: textStorage)
             .compactMap { $0.object as? NSTextStorage }
@@ -87,6 +88,18 @@ final class LineEndingScanner {
     }
     
     
+    /// Return the 1-based line number at the given character index.
+    ///
+    /// - Parameter index: The character index.
+    /// - Returns: The 1-based line number.
+    func lineNumber(at index: Int) -> Int {
+        
+        assert(index <= self.textStorage.string.length)
+        
+        return self.lineEndings.countPrefix { $0.range.upperBound <= index } + 1
+    }
+    
+    
     /// Whether the character at the given index is a line ending inconsistent with the `documentLineEnding`.
     ///
     /// - Parameter characterIndex: The index of character to test.
@@ -124,17 +137,6 @@ final class LineEndingScanner {
         self.inconsistentLineEndings.replace(items: inconsistentLineEndings, in: scanRange, changeInLength: delta)
     }
     
-    
-    /// Scan line endings inconsistent with the document line endings.
-    ///
-    /// - Parameter range: The range to scan.
-    /// - Returns: The ranes of inconsistent line endings with its type.
-    private func scan(in range: NSRange? = nil) -> [ItemRange<LineEnding>] {
-        
-        self.textStorage.string.lineEndingRanges(in: range)
-            .filter { $0.item != self.documentLineEnding }
-    }
-    
 }
 
 

Tests/IncompatibleCharacterTests.swift

@@ -41,14 +41,12 @@ final class IncompatibleCharacterTests: XCTestCase {
         XCTAssertEqual(backslash.character, "\\")
         XCTAssertEqual(backslash.convertedCharacter, "＼")
         XCTAssertEqual(backslash.location, 3)
-        XCTAssertEqual(backslash.lineNumber, 1)
         
         let tilde = incompatibles[1]
         
         XCTAssertEqual(tilde.character, "~")
         XCTAssertEqual(tilde.convertedCharacter, "?")
         XCTAssertEqual(tilde.location, 11)
-        XCTAssertEqual(tilde.lineNumber, 3)
     }
     
     
@@ -64,7 +62,6 @@ final class IncompatibleCharacterTests: XCTestCase {
         XCTAssertEqual(tilde.character, "~")
         XCTAssertEqual(tilde.convertedCharacter, "?")
         XCTAssertEqual(tilde.location, 1)
-        XCTAssertEqual(tilde.lineNumber, 1)
     }
     
     
@@ -78,12 +75,10 @@ final class IncompatibleCharacterTests: XCTestCase {
         XCTAssertEqual(incompatibles[0].character, "👨‍👨‍👦")
         XCTAssertEqual(incompatibles[0].convertedCharacter, "????????")
         XCTAssertEqual(incompatibles[0].location, 7)
-        XCTAssertEqual(incompatibles[0].lineNumber, 1)
         
         XCTAssertEqual(incompatibles[1].character, "🐕")
         XCTAssertEqual(incompatibles[1].convertedCharacter, "??")
         XCTAssertEqual(incompatibles[1].location, 21)
-        XCTAssertEqual(incompatibles[1].lineNumber, 1)
     }
     
 }

Tests/LineEndingScannerTests.swift

@@ -125,6 +125,33 @@ final class LineEndingScannerTests: XCTestCase {
         XCTAssertEqual(scanner.majorLineEnding, .crlf)  // most used new line must be detected
     }
     
+    
+    func testLineNumberCalculation() {
+        
+        let storage = NSTextStorage(string: "dog \n\n cat \n cow \n")
+        let scanner = LineEndingScanner(textStorage: storage, lineEnding: .lf)
+        
+        XCTAssertEqual(scanner.lineNumber(at: 0), 1)
+        XCTAssertEqual(scanner.lineNumber(at: 1), 1)
+        XCTAssertEqual(scanner.lineNumber(at: 4), 1)
+        XCTAssertEqual(scanner.lineNumber(at: 5), 2)
+        XCTAssertEqual(scanner.lineNumber(at: 6), 3)
+        XCTAssertEqual(scanner.lineNumber(at: 11), 3)
+        XCTAssertEqual(scanner.lineNumber(at: 12), 4)
+        XCTAssertEqual(scanner.lineNumber(at: 17), 4)
+        XCTAssertEqual(scanner.lineNumber(at: 18), 5)
+        
+        for _ in 0..<20 {
+            storage.string = String(" 🐶 \n 🐱 \n 🐮 \n".shuffled())
+            
+            for index in (0..<storage.length).shuffled() {
+                XCTAssertEqual(scanner.lineNumber(at: index),
+                               storage.string.lineNumber(at: index),
+                               "At \(index) with string \"\(storage.string)\"")
+            }
+        }
+    }
+    
 }