[shared] Fix Find highlights going stale after edits (#264) (#293)

* [shared] Fix stale find highlights after edits

Clear find highlights on edit and surface a "stale" state in the find bar
so the user knows to retype to refresh. ⌘G / Find Next re-runs the search
when matches were cleared. Mac uses layout-manager temporary attributes so
find backgrounds don't collide with `==highlight==` syntax; iOS keys
removal on the find color value for the same reason. Also clears matches
on external text replacement (file load/revert).

* [shared] Fix find paint losing the right keystroke and ==highlight== bg

Two bugs surfaced after the initial #264 fix landed. Mac's `@Published.$query`
sink re-read `findState.query` when it fired, but `@Published` publishes in
willSet — so the read returned the OLD value and every search ran one keystroke
behind; pass `newQuery` from the sink directly into `performFind`. Both
platforms also painted find color onto `NSTextStorage`, which overwrote any
`==highlight==` markdown background it landed on; Mac now uses
`NSLayoutManager.addTemporaryAttribute` (Apple's pattern for transient UI
highlights, doesn't touch storage), and iOS re-runs the syntax highlighter
on apply/clear since UIKit's `NSLayoutManager` has no temp-attribute API.

Author: Shpigford

Clearly/EditorView.swift

@@ -313,7 +313,6 @@ struct EditorView: NSViewRepresentable {
             context.coordinator.isHighlightingInProgress = true
             context.coordinator.highlighter?.highlightAll(textView.textStorage!, caller: "appearance")
             context.coordinator.isHighlightingInProgress = false
-            context.coordinator.restoreFindHighlightsIfNeeded()
 
             // Refresh ruler when appearance/font changes
             context.coordinator.gutterView?.appearanceDidChange()
@@ -334,7 +333,16 @@ struct EditorView: NSViewRepresentable {
             context.coordinator.isHighlightingInProgress = true
             context.coordinator.highlighter?.highlightAll(textView.textStorage!, caller: "externalText")
             context.coordinator.isHighlightingInProgress = false
-            context.coordinator.restoreFindHighlightsIfNeeded()
+            // External text replacement (file load/revert) — old match ranges are stale.
+            context.coordinator.clearFindHighlights()
+            if let findState = context.coordinator.findState, findState.isVisible, findState.activeMode == .edit {
+                DispatchQueue.main.async { [weak findState] in
+                    guard let findState, findState.activeMode == .edit else { return }
+                    findState.matchCount = 0
+                    findState.currentIndex = 0
+                    findState.resultsAreStale = true
+                }
+            }
             context.coordinator.gutterView?.textDidChange()
             context.coordinator.gutterView?.selectionDidChange(selectedRange: textView.selectedRange())
             context.coordinator.isUpdating = false
@@ -521,12 +529,15 @@ struct EditorView: NSViewRepresentable {
 
             state.$query
                 .removeDuplicates()
-                .sink { [weak self] _ in
+                .sink { [weak self] newQuery in
                     guard let self,
                           let findState = self.findState,
                           findState.isVisible,
                           findState.activeMode == .edit else { return }
-                    self.performFind()
+                    // `@Published` fires in willSet — `findState.query` still
+                    // reads the OLD value here. Pass `newQuery` explicitly so
+                    // performFind doesn't run a keystroke behind.
+                    self.performFind(query: newQuery)
                 }
                 .store(in: &findCancellables)
 
@@ -602,7 +613,6 @@ struct EditorView: NSViewRepresentable {
                         sv.reflectScrolledClipView(sv.contentView)
                     }
                     self.invalidateVisibleRegion(of: textView)
-                    self.restoreFindHighlightsIfNeeded()
                 }
                 pendingFullHighlightWork = work
                 DispatchQueue.main.asyncAfter(deadline: .now() + 0.3, execute: work)
@@ -619,8 +629,18 @@ struct EditorView: NSViewRepresentable {
             // the visible rect so large documents don't repaint end-to-end.
             invalidateVisibleRegion(of: textView)
 
-            // Re-apply find highlights after syntax highlighting
-            restoreFindHighlightsIfNeeded()
+            // Clear on edit; user retypes the query to refresh (#264).
+            if let findState, findState.isVisible, !matchRanges.isEmpty {
+                clearFindHighlights()
+                if findState.activeMode == .edit {
+                    DispatchQueue.main.async { [weak findState] in
+                        guard let findState, findState.activeMode == .edit else { return }
+                        findState.matchCount = 0
+                        findState.currentIndex = 0
+                        findState.resultsAreStale = true
+                    }
+                }
+            }
 
             // Update line number ruler
             gutterView?.textDidChange()
@@ -763,17 +783,9 @@ struct EditorView: NSViewRepresentable {
 
         // MARK: - Find
 
-        func restoreFindHighlightsIfNeeded() {
-            guard findState?.isVisible == true, !(findState?.query.isEmpty ?? true) else { return }
-            // Re-apply cached highlight colors without re-running the full find
-            // (which would scroll to the first match on every keystroke).
-            guard !matchRanges.isEmpty else { return }
-            applyFindHighlights()
-        }
-
-        func performFind() {
+        func performFind(query overrideQuery: String? = nil) {
             guard let textView, let findState else { return }
-            let query = findState.query
+            let query = overrideQuery ?? findState.query
             clearFindHighlights()
 
             guard !query.isEmpty else {
@@ -785,6 +797,7 @@ struct EditorView: NSViewRepresentable {
                           findState.activeMode == .edit else { return }
                     findState.matchCount = 0
                     findState.currentIndex = 0
+                    findState.resultsAreStale = false
                 }
                 return
             }
@@ -801,6 +814,7 @@ struct EditorView: NSViewRepresentable {
                       findState.activeMode == .edit else { return }
                 findState.matchCount = ranges.count
                 findState.currentIndex = ranges.isEmpty ? 0 : 1
+                findState.resultsAreStale = false
             }
 
             if !ranges.isEmpty {
@@ -809,6 +823,12 @@ struct EditorView: NSViewRepresentable {
         }
 
         func navigateToNextMatch() {
+            // After clear-on-edit, matchRanges is empty but the user's query is
+            // still in the find bar — treat ⌘G / Find Next as a re-run trigger.
+            if matchRanges.isEmpty, let findState, !findState.query.isEmpty {
+                performFind()
+                return
+            }
             guard !matchRanges.isEmpty else { return }
             currentMatchIdx = (currentMatchIdx + 1) % matchRanges.count
             applyFindHighlights()
@@ -822,6 +842,10 @@ struct EditorView: NSViewRepresentable {
         }
 
         func navigateToPreviousMatch() {
+            if matchRanges.isEmpty, let findState, !findState.query.isEmpty {
+                performFind()
+                return
+            }
             guard !matchRanges.isEmpty else { return }
             currentMatchIdx = (currentMatchIdx - 1 + matchRanges.count) % matchRanges.count
             applyFindHighlights()
@@ -834,31 +858,27 @@ struct EditorView: NSViewRepresentable {
             }
         }
 
+        // Find highlights live on the layout manager via temporary attributes,
+        // not on text storage. This is Apple's recommended pattern for
+        // transient UI highlighting and means find painting never overwrites
+        // `==highlight==` markdown backgrounds (which DO live on storage).
         private func applyFindHighlights() {
-            guard let textView else { return }
+            guard let textView, let layoutManager = textView.layoutManager else { return }
             let storage = textView.textStorage!
-
-            // Clear existing find highlights first
             let fullRange = NSRange(location: 0, length: storage.length)
-            storage.beginEditing()
-            storage.removeAttribute(.backgroundColor, range: fullRange)
-
-            // Apply highlight to all matches
+            layoutManager.removeTemporaryAttribute(.backgroundColor, forCharacterRange: fullRange)
             for (i, range) in matchRanges.enumerated() {
                 guard range.upperBound <= storage.length else { continue }
                 let color = (i == currentMatchIdx) ? Theme.findCurrentHighlightColor : Theme.findHighlightColor
-                storage.addAttribute(.backgroundColor, value: color, range: range)
+                layoutManager.addTemporaryAttribute(.backgroundColor, value: color, forCharacterRange: range)
             }
-            storage.endEditing()
         }
 
         func clearFindHighlights() {
-            guard let textView else { return }
+            guard let textView, let layoutManager = textView.layoutManager else { return }
             let storage = textView.textStorage!
             let fullRange = NSRange(location: 0, length: storage.length)
-            storage.beginEditing()
-            storage.removeAttribute(.backgroundColor, range: fullRange)
-            storage.endEditing()
+            layoutManager.removeTemporaryAttribute(.backgroundColor, forCharacterRange: fullRange)
             matchRanges = []
             currentMatchIdx = 0
         }

Clearly/FindBarView.swift

@@ -23,7 +23,7 @@ struct FindBarView: View {
                 )
                 .frame(minWidth: 120)
 
-                if !findState.query.isEmpty {
+                if !findState.query.isEmpty && !findState.resultsAreStale {
                     if findState.matchCount > 0 {
                         Text("\(findState.currentIndex) of \(findState.matchCount)")
                             .font(.system(size: 11, weight: .medium))
@@ -49,10 +49,10 @@ struct FindBarView: View {
             )
 
             HStack(spacing: 2) {
-                FindNavButton(icon: "chevron.left", disabled: findState.matchCount == 0) {
+                FindNavButton(icon: "chevron.left", disabled: !findState.canNavigate) {
                     findState.navigateToPrevious?()
                 }
-                FindNavButton(icon: "chevron.right", disabled: findState.matchCount == 0) {
+                FindNavButton(icon: "chevron.right", disabled: !findState.canNavigate) {
                     findState.navigateToNext?()
                 }
             }

Clearly/LiveEditorView.swift

@@ -429,6 +429,7 @@ struct LiveEditorView: NSViewRepresentable {
                     guard self.parent.findState?.activeMode == .edit || self.parent.findState?.isVisible == false else { return }
                     self.parent.findState?.matchCount = matchCount
                     self.parent.findState?.currentIndex = currentIndex
+                    self.parent.findState?.resultsAreStale = false
                 }
 
             case "openLink":

Clearly/PreviewView.swift

@@ -644,6 +644,7 @@ struct PreviewView: NSViewRepresentable {
                     guard self.findState?.activeMode == .preview else { return }
                     self.findState?.matchCount = count
                     self.findState?.currentIndex = count > 0 ? 1 : 0
+                    self.findState?.resultsAreStale = false
                 }
             }
         }
@@ -695,6 +696,7 @@ struct PreviewView: NSViewRepresentable {
                 guard self?.findState?.activeMode == .preview || self?.findState?.isVisible == false else { return }
                 self?.findState?.matchCount = 0
                 self?.findState?.currentIndex = 0
+                self?.findState?.resultsAreStale = false
             }
         }
 

Clearly/iOS/EditorView_iOS.swift

@@ -128,6 +128,7 @@ struct EditorView_iOS: UIViewRepresentable {
                 guard let state, state.activeMode == .edit else { return }
                 state.matchCount = ranges.count
                 state.currentIndex = ranges.isEmpty ? 0 : 1
+                state.resultsAreStale = false
                 _ = self
             }
 
@@ -137,6 +138,12 @@ struct EditorView_iOS: UIViewRepresentable {
         }
 
         private func navigateToNextMatch() {
+            // After clear-on-edit, matchRanges is empty but the query is still
+            // in the find bar — treat Next as a re-run trigger.
+            if matchRanges.isEmpty, let state = attachedFindState, !state.query.isEmpty {
+                performFind(for: state)
+                return
+            }
             guard !matchRanges.isEmpty else { return }
             currentMatchIdx = (currentMatchIdx + 1) % matchRanges.count
             applyFindHighlights()
@@ -149,6 +156,10 @@ struct EditorView_iOS: UIViewRepresentable {
         }
 
         private func navigateToPreviousMatch() {
+            if matchRanges.isEmpty, let state = attachedFindState, !state.query.isEmpty {
+                performFind(for: state)
+                return
+            }
             guard !matchRanges.isEmpty else { return }
             currentMatchIdx = (currentMatchIdx - 1 + matchRanges.count) % matchRanges.count
             applyFindHighlights()
@@ -160,12 +171,17 @@ struct EditorView_iOS: UIViewRepresentable {
             }
         }
 
+        // UIKit's NSLayoutManager has no temporary-attribute API, so find
+        // highlights have to use storage attributes. To prevent find color
+        // from clobbering `==highlight==` markdown backgrounds, we re-run
+        // the syntax highlighter (which resets bg per paragraph) before
+        // every paint — and again on clear so dismissed find never leaves
+        // missing backgrounds behind.
         private func applyFindHighlights() {
             guard let textView else { return }
             let storage = textView.textStorage
-            let fullRange = NSRange(location: 0, length: storage.length)
+            rerunSyntaxHighlighter(on: storage)
             storage.beginEditing()
-            storage.removeAttribute(.backgroundColor, range: fullRange)
             for (i, range) in matchRanges.enumerated() {
                 guard range.upperBound <= storage.length else { continue }
                 let color = (i == currentMatchIdx) ? Theme.findCurrentHighlightColor : Theme.findHighlightColor
@@ -176,22 +192,16 @@ struct EditorView_iOS: UIViewRepresentable {
 
         private func clearFindHighlights() {
             guard let textView else { return }
-            let storage = textView.textStorage
-            let fullRange = NSRange(location: 0, length: storage.length)
-            storage.beginEditing()
-            storage.removeAttribute(.backgroundColor, range: fullRange)
-            storage.endEditing()
+            rerunSyntaxHighlighter(on: textView.textStorage)
             matchRanges = []
             currentMatchIdx = 0
         }
 
-        /// Called at the tail of `textViewDidChange` so the syntax-highlighter's
-        /// attribute rewrite doesn't wipe find backgrounds. Mirrors the Mac
-        /// `restoreFindHighlightsIfNeeded` pattern — if the query is still
-        /// active, re-run the search so match ranges track the edit too.
-        private func restoreFindHighlightsIfNeeded() {
-            guard let state = attachedFindState, state.isVisible, !state.query.isEmpty else { return }
-            performFind(for: state)
+        private func rerunSyntaxHighlighter(on storage: NSTextStorage) {
+            let wasHighlighting = isHighlighting
+            isHighlighting = true
+            highlighter.highlightAll(storage, caller: "find-rerun")
+            isHighlighting = wasHighlighting
         }
 
         private func scrollToRange(_ range: NSRange) {
@@ -221,6 +231,20 @@ struct EditorView_iOS: UIViewRepresentable {
             textView.selectedRange = clamped
             isHighlighting = false
             lastAppliedText = newText
+
+            // External text replacement (file load/revert) — old match ranges are stale.
+            if !matchRanges.isEmpty {
+                matchRanges = []
+                currentMatchIdx = 0
+                if let state = attachedFindState, state.isVisible, state.activeMode == .edit {
+                    DispatchQueue.main.async { [weak state] in
+                        guard let state, state.activeMode == .edit else { return }
+                        state.matchCount = 0
+                        state.currentIndex = 0
+                        state.resultsAreStale = true
+                    }
+                }
+            }
         }
 
         // MARK: - UITextViewDelegate
@@ -272,7 +296,18 @@ struct EditorView_iOS: UIViewRepresentable {
             lastAppliedText = newText
             parent.text = newText
 
-            restoreFindHighlightsIfNeeded()
+            // Clear on edit; user retypes the query to refresh (#264).
+            if let state = attachedFindState, state.isVisible, !matchRanges.isEmpty {
+                clearFindHighlights()
+                if state.activeMode == .edit {
+                    DispatchQueue.main.async { [weak state] in
+                        guard let state, state.activeMode == .edit else { return }
+                        state.matchCount = 0
+                        state.currentIndex = 0
+                        state.resultsAreStale = true
+                    }
+                }
+            }
 
             let token = UUID()
             pendingBindingUpdateToken = token

Clearly/iOS/FindOverlay_iOS.swift

@@ -23,7 +23,7 @@ struct FindOverlay_iOS: View {
                     .focused($isFieldFocused)
                     .onSubmit { findState.navigateToNext?() }
 
-                if !findState.query.isEmpty {
+                if !findState.query.isEmpty && !findState.resultsAreStale {
                     if findState.matchCount > 0 {
                         Text("\(findState.currentIndex) of \(findState.matchCount)")
                             .font(Theme.Typography.findCount)
@@ -62,10 +62,10 @@ struct FindOverlay_iOS: View {
             )
 
             HStack(spacing: 2) {
-                FindNavButton_iOS(icon: "chevron.up", disabled: findState.matchCount == 0) {
+                FindNavButton_iOS(icon: "chevron.up", disabled: !findState.canNavigate) {
                     findState.navigateToPrevious?()
                 }
-                FindNavButton_iOS(icon: "chevron.down", disabled: findState.matchCount == 0) {
+                FindNavButton_iOS(icon: "chevron.down", disabled: !findState.canNavigate) {
                     findState.navigateToNext?()
                 }
             }

Packages/ClearlyCore/Sources/ClearlyCore/State/FindState.swift

@@ -7,6 +7,7 @@ public final class FindState: ObservableObject {
     @Published public var query = ""
     @Published public var matchCount = 0
     @Published public var currentIndex = 0 // 1-based, 0 = no matches
+    @Published public var resultsAreStale = false
     @Published public var focusRequest = UUID()
     public var activeMode: ViewMode = .edit
 
@@ -15,6 +16,10 @@ public final class FindState: ObservableObject {
     public var previewNavigateToNext: (() -> Void)?
     public var previewNavigateToPrevious: (() -> Void)?
 
+    public var canNavigate: Bool {
+        !query.isEmpty && (resultsAreStale || matchCount > 0)
+    }
+
     public var navigateToNext: (() -> Void)? {
         switch activeMode {
         case .edit: