Update view on input changes

Sources/LaTeXSwiftUI/LaTeX.swift

@@ -159,7 +159,7 @@ public struct LaTeX: View {
   // MARK: Private properties
 
   /// The view's renderer.
-  @StateObject private var renderer: Renderer
+  @StateObject private var renderer = Renderer()
 
   /// The view's preload task, if any.
   @State private var preloadTask: Task<(), Never>?
@@ -171,7 +171,6 @@ public struct LaTeX: View {
   /// - Parameter latex: The LaTeX input.
   public init(_ latex: String) {
     self.latex = latex
-    _renderer = StateObject(wrappedValue: Renderer(latex: latex))
   }
 
   // MARK: View body
@@ -239,6 +238,7 @@ extension LaTeX {
   ///   cached.
   private func isCached() -> Bool {
     renderer.isCached(
+      latex: latex,
       unencodeHTML: unencodeHTML,
       parsingMode: parsingMode,
       processEscapes: processEscapes,
@@ -250,6 +250,7 @@ extension LaTeX {
   /// Renders the view's components.
   @Sendable private func renderAsync() async {
     await renderer.render(
+      latex: latex,
       unencodeHTML: unencodeHTML,
       parsingMode: parsingMode,
       processEscapes: processEscapes,
@@ -263,6 +264,7 @@ extension LaTeX {
   /// - Returns: The rendered components.
   private func renderSync() -> [ComponentBlock] {
     renderer.renderSync(
+      latex: latex,
       unencodeHTML: unencodeHTML,
       parsingMode: parsingMode,
       processEscapes: processEscapes,

Sources/LaTeXSwiftUI/Models/Renderer.swift

@@ -38,10 +38,22 @@ import Cocoa
 /// values.
 internal class Renderer: ObservableObject {
 
-  // MARK: Public properties
+  // MARK: Types
+
+  /// A set of values used to create an array of parsed component blocks.
+  struct ParsingSource: Equatable {
+
+    /// The LaTeX input.
+    let latex: String
+
+    /// Whether or not the HTML should be unencoded.
+    let unencodeHTML: Bool
+
+    /// The parsing mode.
+    let parsingMode: LaTeX.ParsingMode
+  }
 
-  /// The view's input string.
-  let latex: String
+  // MARK: Public properties
 
   /// Whether or not the view's blocks have been rendered.
   @MainActor @Published var rendered: Bool = false
@@ -57,18 +69,12 @@ internal class Renderer: ObservableObject {
   /// The LaTeX input's parsed blocks.
   private var _parsedBlocks: [ComponentBlock]? = nil
 
+  /// The set of values used to create the parsed blocks.
+  private var _parsingSource: ParsingSource? = nil
+
   /// Semaphore for thread-safe access to `_parsedBlocks`.
   private var _parsedBlocksSemaphore = DispatchSemaphore(value: 1)
 
-  // MARK: Initializers
-
-  /// Initializes a render state with an input string.
-  ///
-  /// - Parameter latex: The view's input string.
-  init(latex: String) {
-    self.latex = latex
-  }
-
 }
 
 // MARK: Public methods
@@ -78,14 +84,15 @@ extension Renderer {
   /// Returns whether the view's components are cached.
   ///
   /// - Parameters:
+  ///   - latex: The LaTeX input string.
   ///   - unencodeHTML: The `unencodeHTML` environment variable.
   ///   - parsingMode: The `parsingMode` environment variable.
   ///   - processEscapes: The `processEscapes` environment variable.
   ///   - errorMode: The `errorMode` environment variable.
   ///   - font: The `font environment` variable.
   ///   - displayScale: The `displayScale` environment variable.
-  ///   - texOptions: The `texOptions` environment variable.
   func isCached(
+    latex: String,
     unencodeHTML: Bool,
     parsingMode: LaTeX.ParsingMode,
     processEscapes: Bool,
@@ -95,7 +102,7 @@ extension Renderer {
   ) -> Bool {
     let texOptions = TeXInputProcessorOptions(processEscapes: processEscapes, errorMode: errorMode)
     return blocksExistInCache(
-      parsedBlocks(unencodeHTML: unencodeHTML, parsingMode: parsingMode),
+      parsedBlocks(latex: latex, unencodeHTML: unencodeHTML, parsingMode: parsingMode),
       font: font,
       displayScale: displayScale,
       texOptions: texOptions)
@@ -104,14 +111,15 @@ extension Renderer {
   /// Renders the view's components synchronously.
   ///
   /// - Parameters:
+  ///   - latex: The LaTeX input string.
   ///   - unencodeHTML: The `unencodeHTML` environment variable.
   ///   - parsingMode: The `parsingMode` environment variable.
   ///   - processEscapes: The `processEscapes` environment variable.
   ///   - errorMode: The `errorMode` environment variable.
   ///   - font: The `font environment` variable.
   ///   - displayScale: The `displayScale` environment variable.
-  ///   - texOptions: The `texOptions` environment variable.
   func renderSync(
+    latex: String,
     unencodeHTML: Bool,
     parsingMode: LaTeX.ParsingMode,
     processEscapes: Bool,
@@ -121,7 +129,7 @@ extension Renderer {
   ) -> [ComponentBlock] {
     let texOptions = TeXInputProcessorOptions(processEscapes: processEscapes, errorMode: errorMode)
     return render(
-      blocks: parsedBlocks(unencodeHTML: unencodeHTML, parsingMode: parsingMode),
+      blocks: parsedBlocks(latex: latex, unencodeHTML: unencodeHTML, parsingMode: parsingMode),
       font: font,
       displayScale: displayScale,
       texOptions: texOptions)
@@ -130,14 +138,15 @@ extension Renderer {
   /// Renders the view's components asynchronously.
   ///
   /// - Parameters:
+  ///   - latex: The LaTeX input string.
   ///   - unencodeHTML: The `unencodeHTML` environment variable.
   ///   - parsingMode: The `parsingMode` environment variable.
   ///   - processEscapes: The `processEscapes` environment variable.
   ///   - errorMode: The `errorMode` environment variable.
   ///   - font: The `font environment` variable.
   ///   - displayScale: The `displayScale` environment variable.
-  ///   - texOptions: The `texOptions` environment variable.
   func render(
+    latex: String,
     unencodeHTML: Bool,
     parsingMode: LaTeX.ParsingMode,
     processEscapes: Bool,
@@ -156,7 +165,7 @@ extension Renderer {
 
     let texOptions = TeXInputProcessorOptions(processEscapes: processEscapes, errorMode: errorMode)
     let renderedBlocks = await render(
-      blocks: parsedBlocks(unencodeHTML: unencodeHTML, parsingMode: parsingMode),
+      blocks: parsedBlocks(latex: latex, unencodeHTML: unencodeHTML, parsingMode: parsingMode),
       font: font,
       displayScale: displayScale,
       texOptions: texOptions)
@@ -313,21 +322,26 @@ extension Renderer {
   /// Gets the LaTeX input's parsed blocks.
   ///
   /// - Parameters:
+  ///   - latex: The LaTeX input string.
   ///   - unencodeHTML: The `unencodeHTML` environment variable.
   ///   - parsingMode: The `parsingMode` environment variable.
   /// - Returns: The parsed blocks.
   private func parsedBlocks(
+    latex: String,
     unencodeHTML: Bool,
     parsingMode: LaTeX.ParsingMode
   ) -> [ComponentBlock] {
     _parsedBlocksSemaphore.wait()
     defer { _parsedBlocksSemaphore.signal() }
-    if let _parsedBlocks {
+
+    let currentSource = ParsingSource(latex: latex, unencodeHTML: unencodeHTML, parsingMode: parsingMode)
+    if let _parsedBlocks, _parsingSource == currentSource {
       return _parsedBlocks
     }
 
     let blocks = Parser.parse(unencodeHTML ? latex.htmlUnescape() : latex, mode: parsingMode)
     _parsedBlocks = blocks
+    _parsingSource = currentSource
     return blocks
   }
 

Sources/LaTeXSwiftUI/Views/ComponentBlockText.swift

@@ -72,6 +72,6 @@ struct ComponentBlockTextPreviews: PreviewProvider {
   static var previews: some View {
     ComponentBlockText(block: ComponentBlock(components: [
       Component(text: "Hello, World!", type: .text)
-    ]), renderer: Renderer(latex: "Hello, World!"))
+    ]), renderer: Renderer())
   }
 }

Sources/LaTeXSwiftUI/Views/ComponentBlocksText.swift

@@ -57,6 +57,6 @@ struct ComponentBlocksTextPreviews: PreviewProvider {
     ComponentBlocksText(blocks: [ComponentBlock(components: [
       Component(text: "Hello, World!", type: .text)
     ])], forceInline: false)
-    .environmentObject(Renderer(latex: "Hello, World!"))
+    .environmentObject(Renderer())
   }
 }

Sources/LaTeXSwiftUI/Views/ComponentBlocksViews.swift

@@ -97,6 +97,6 @@ struct ComponentBlocksViewsPreviews: PreviewProvider {
     ComponentBlocksViews(blocks: [ComponentBlock(components: [
       Component(text: "Hello, World!", type: .text)
     ])])
-    .environmentObject(Renderer(latex: "Hello, World!"))
+    .environmentObject(Renderer())
   }
 }