Auto-hide terminal scroll bar fixes 2674

Sources/AppDelegate.swift

@@ -5809,8 +5809,8 @@ final class AppDelegate: NSObject, NSApplicationDelegate, UNUserNotificationCent
     func refreshTerminalSurfacesAfterGhosttyConfigReload(source: String) {
         var refreshedCount = 0
         forEachTerminalPanel { terminalPanel in
-            terminalPanel.hostedView.reconcileGeometryNow()
             terminalPanel.hostedView.refreshHostBackgroundAfterGhosttyConfigReload()
+            terminalPanel.hostedView.reconcileGeometryNow()
             terminalPanel.surface.forceRefresh(reason: "appDelegate.refreshAfterGhosttyConfigReload")
             refreshedCount += 1
         }

Sources/GhosttyTerminalView.swift

@@ -1181,6 +1181,11 @@ private final class GhosttySurfaceCallbackContext {
 // MARK: - Ghostty App Singleton
 
 class GhosttyApp {
+    enum ScrollbarVisibility: String {
+        case system
+        case never
+    }
+
     static let shared = GhosttyApp()
     private static let releaseBundleIdentifier = "com.cmuxterm.app"
     private static let backgroundLogTimestampFormatter: ISO8601DateFormatter = {
@@ -2468,6 +2473,17 @@ class GhosttyApp {
         return found && enabled
     }
 
+    func scrollbarVisibility() -> ScrollbarVisibility {
+        guard let config else { return .system }
+        var value: UnsafePointer<Int8>?
+        let key = "scrollbar"
+        guard ghostty_config_get(config, &value, key, UInt(key.lengthOfBytes(using: .utf8))),
+              let value else {
+            return .system
+        }
+        return ScrollbarVisibility(rawValue: String(cString: value)) ?? .system
+    }
+
     func appleScriptAutomationEnabled() -> Bool {
         guard let config else { return false }
         var enabled = false
@@ -8532,6 +8548,7 @@ final class GhosttySurfaceScrollView: NSView {
     private var searchOverlayMutationGeneration: UInt64 = 0
     private var observers: [NSObjectProtocol] = []
     private var windowObservers: [NSObjectProtocol] = []
+    private var scrollbarTrackingArea: NSTrackingArea?
     private var isLiveScrolling = false
     private var lastSentRow: Int?
     /// Tracks whether the user has scrolled away from the bottom to review scrollback.
@@ -8777,6 +8794,7 @@ final class GhosttySurfaceScrollView: NSView {
         backgroundView.layer?.isOpaque = initialTerminalBackground.alphaComponent >= 1.0
         addSubview(backgroundView)
         addSubview(scrollView)
+        synchronizeScrollbarAppearance()
         inactiveOverlayView.wantsLayer = true
         inactiveOverlayView.layer?.backgroundColor = NSColor.clear.cgColor
         inactiveOverlayView.isHidden = true
@@ -9072,6 +9090,37 @@ final class GhosttySurfaceScrollView: NSView {
     // Avoid stealing focus on scroll; focus is managed explicitly by the surface view.
     override var acceptsFirstResponder: Bool { false }
 
+    override func mouseMoved(with event: NSEvent) {
+        super.mouseMoved(with: event)
+        guard scrollView.hasVerticalScroller,
+              NSScroller.preferredScrollerStyle == .legacy else { return }
+        scrollView.flashScrollers()
+    }
+
+    override func updateTrackingAreas() {
+        if let scrollbarTrackingArea {
+            removeTrackingArea(scrollbarTrackingArea)
+            self.scrollbarTrackingArea = nil
+        }
+
+        super.updateTrackingAreas()
+
+        guard scrollView.hasVerticalScroller,
+              let scroller = scrollView.verticalScroller else { return }
+
+        let trackingArea = NSTrackingArea(
+            rect: convert(scroller.bounds, from: scroller),
+            options: [
+                .mouseMoved,
+                .activeInKeyWindow,
+            ],
+            owner: self,
+            userInfo: nil
+        )
+        addTrackingArea(trackingArea)
+        scrollbarTrackingArea = trackingArea
+    }
+
     override func layout() {
         super.layout()
         synchronizeGeometryAndContent()
@@ -9769,6 +9818,7 @@ final class GhosttySurfaceScrollView: NSView {
     }
 
     func refreshHostBackgroundAfterGhosttyConfigReload() {
+        synchronizeScrollbarAppearance()
         surfaceView.applySurfaceBackground()
         surfaceView.applyWindowBackgroundIfActive()
     }
@@ -11225,6 +11275,16 @@ final class GhosttySurfaceScrollView: NSView {
         synchronizeScrollView()
     }
 
+    private func synchronizeScrollbarAppearance() {
+        scrollView.hasVerticalScroller = GhosttyApp.shared.scrollbarVisibility() != .never
+        // Mirror upstream Ghostty: keep overlay scrollers even when the
+        // system preference is legacy so terminal content never sits beneath a
+        // permanently reserved scrollbar gutter.
+        scrollView.autohidesScrollers = false
+        scrollView.scrollerStyle = .overlay
+        updateTrackingAreas()
+    }
+
     private func handlePreferredScrollerStyleChange() {
         guard Thread.isMainThread else {
             DispatchQueue.main.async { [weak self] in
@@ -11233,6 +11293,8 @@ final class GhosttySurfaceScrollView: NSView {
             return
         }
 
+        synchronizeScrollbarAppearance()
+
         // Retile just the scroll view so contentSize reflects the current
         // scrollbar mode without perturbing viewport origin or hosted view
         // geometry; the broader reconcile path caused visible content glitches.

cmuxTests/TerminalAndGhosttyTests.swift

@@ -2209,7 +2209,7 @@ final class GhosttySurfaceOverlayTests: XCTestCase {
         XCTAssertTrue(state.isHidden)
     }
 
-    func testPreferredScrollerStyleChangeRecalculatesTerminalSurfaceWidth() {
+    func testPreferredScrollerStyleChangeRestoresOverlayScrollbarWidth() {
         let surface = TerminalSurface(
             tabId: UUID(),
             context: GHOSTTY_SURFACE_CONTEXT_SPLIT,
@@ -2289,32 +2289,17 @@ final class GhosttySurfaceOverlayTests: XCTestCase {
         NotificationCenter.default.post(name: NSScroller.preferredScrollerStyleDidChangeNotification, object: nil)
         RunLoop.current.run(until: Date().addingTimeInterval(0.05))
 
-        XCTAssertEqual(scrollView.scrollerStyle, .legacy)
-        assertPendingSurfaceWidth(
-            legacyContentWidth,
-            "Preferred scroller style changes should recalculate the terminal grid width immediately"
-        )
-
-        scrollView.scrollerStyle = .overlay
-        scrollView.layoutSubtreeIfNeeded()
-        let overlayContentWidth = scrollView.contentSize.width
-        XCTAssertGreaterThan(
-            overlayContentWidth,
-            legacyContentWidth,
-            "Overlay scrollbars should restore the full terminal content width"
-        )
-        assertPendingSurfaceWidth(
-            legacyContentWidth,
-            "Changing the scroll view style alone should leave the terminal grid stale until the scroller-style observer runs"
-        )
-
-        NotificationCenter.default.post(name: NSScroller.preferredScrollerStyleDidChangeNotification, object: nil)
-        RunLoop.current.run(until: Date().addingTimeInterval(0.05))
-
+        let restoredContentWidth = scrollView.contentSize.width
         XCTAssertEqual(scrollView.scrollerStyle, .overlay)
+        XCTAssertEqual(
+            restoredContentWidth,
+            initialContentWidth,
+            accuracy: 0.5,
+            "Preferred scroller style changes should restore Ghostty's overlay scrollbar behavior so terminal content is not occluded by a persistent gutter"
+        )
         assertPendingSurfaceWidth(
-            overlayContentWidth,
-            "Preferred scroller style changes should also restore the wider terminal grid when overlay scrollbars return"
+            restoredContentWidth,
+            "Preferred scroller style changes should restore the wider terminal grid when overlay scrollbars return"
         )
     }