Transcript Incremental Projection

Nucleic-Session: 0FFD007B-0696-4517-9429-129C7B0FD5AC
Co-authored-by: Nucleic <[email protected]>

NucleicRemote/NucleicRemote/Views/Transcript/MarkdownText.swift

@@ -40,14 +40,19 @@ struct MarkdownText: View {
     /// (scrolling, a sibling row streaming) and on every chat reopen, yet structural parsing
     /// is independent of `bodySize` — so the source string is a complete key. Bounded;
     /// `NSCache` also evicts under memory pressure.
+    ///
+    /// The whole parse pipeline (both caches and the statics below) is `nonisolated`: `prewarm`
+    /// runs it from a detached background task by design, and as `View` statics they'd otherwise
+    /// be implicitly MainActor (a Swift 6 error for that call). `(unsafe)` on the caches is
+    /// sound because `NSCache` is thread-safe and the boxed values are immutable.
     private final class ParsedBlocks { let blocks: [Block]; init(_ b: [Block]) { self.blocks = b } }
-    private static let blockCache: NSCache<NSString, ParsedBlocks> = {
+    nonisolated(unsafe) private static let blockCache: NSCache<NSString, ParsedBlocks> = {
         let cache = NSCache<NSString, ParsedBlocks>()
         cache.countLimit = 2048
         return cache
     }()
 
-    private static func parse(_ markdown: String) -> [Block] {
+    nonisolated private static func parse(_ markdown: String) -> [Block] {
         let key = markdown as NSString
         if let hit = blockCache.object(forKey: key) { return hit.blocks }
         let blocks = parseUncached(markdown)
@@ -55,7 +60,7 @@ struct MarkdownText: View {
         return blocks
     }
 
-    private static func parseUncached(_ markdown: String) -> [Block] {
+    nonisolated private static func parseUncached(_ markdown: String) -> [Block] {
         var blocks: [Block] = []
         var textBuffer: [String] = []
         func flush() {
@@ -100,12 +105,12 @@ struct MarkdownText: View {
 
     /// A GitHub-style table: a `|`-bearing header line immediately followed by a
     /// `|---|:--:|` separator line.
-    private static func isTableStart(_ lines: [String], _ index: Int) -> Bool {
+    nonisolated private static func isTableStart(_ lines: [String], _ index: Int) -> Bool {
         guard lines[index].contains("|"), index + 1 < lines.count else { return false }
         return isSeparatorRow(lines[index + 1])
     }
 
-    private static func isSeparatorRow(_ line: String) -> Bool {
+    nonisolated private static func isSeparatorRow(_ line: String) -> Bool {
         let cells = tableCells(line)
         guard !cells.isEmpty else { return false }
         return cells.allSatisfy { cell in
@@ -115,7 +120,7 @@ struct MarkdownText: View {
 
     /// Split a table row into trimmed cells, dropping the empties created by the
     /// leading/trailing pipes.
-    private static func tableCells(_ line: String) -> [String] {
+    nonisolated private static func tableCells(_ line: String) -> [String] {
         var trimmed = line.trimmingCharacters(in: .whitespaces)
         if trimmed.hasPrefix("|") { trimmed.removeFirst() }
         if trimmed.hasSuffix("|") { trimmed.removeLast() }
@@ -189,7 +194,7 @@ struct MarkdownText: View {
     /// Classify one raw prose line. Headings are checked before bullets (a heading marker wins),
     /// and the plain case keeps the *raw* line (not the trimmed one) exactly as the old cascade
     /// did — the inline parser preserves leading whitespace under `.inlineOnlyPreservingWhitespace`.
-    private static func classify(_ raw: String) -> LineStyle {
+    nonisolated private static func classify(_ raw: String) -> LineStyle {
         let trimmed = raw.trimmingCharacters(in: .whitespaces)
         if trimmed.isEmpty { return .blank }
         // Headings scale relative to the base prose size so the hierarchy holds at any base and
@@ -219,7 +224,7 @@ struct MarkdownText: View {
     }
 
     /// Returns the content after a `- `, `* `, `+ ` or `N. ` list marker, else nil.
-    private static func bulletContent(_ trimmed: String) -> String? {
+    nonisolated private static func bulletContent(_ trimmed: String) -> String? {
         for marker in ["- ", "* ", "+ "] where trimmed.hasPrefix(marker) {
             return String(trimmed.dropFirst(marker.count))
         }
@@ -241,13 +246,13 @@ struct MarkdownText: View {
     /// recur across re-renders and reopens, so memoize the parsed result. Independent of
     /// `bodySize` (callers apply the font), so the source string is a complete key.
     private final class InlineBox { let value: AttributedString; init(_ v: AttributedString) { self.value = v } }
-    private static let inlineCache: NSCache<NSString, InlineBox> = {
+    nonisolated(unsafe) private static let inlineCache: NSCache<NSString, InlineBox> = {
         let cache = NSCache<NSString, InlineBox>()
         cache.countLimit = 16384
         return cache
     }()
 
-    private static func attributedInline(_ string: String) -> AttributedString {
+    nonisolated private static func attributedInline(_ string: String) -> AttributedString {
         let key = string as NSString
         if let hit = inlineCache.object(forKey: key) { return hit.value }
         let options = AttributedString.MarkdownParsingOptions(
@@ -272,7 +277,7 @@ struct MarkdownText: View {
     /// keyed only by the source string (independent of `bodySize`), so a warm value equals what
     /// the main thread would compute, and a repeat call is a cheap cache hit. Cooperatively
     /// cancellable — a huge transcript's warm loop bails the moment its owning task is cancelled.
-    static func prewarm(_ markdown: String) {
+    nonisolated static func prewarm(_ markdown: String) {
         for block in parse(markdown) {          // also warms the block cache
             if Task.isCancelled { return }
             switch block {