Fix browser webview divider resizing

.github/swift-file-length-budget.tsv

@@ -10,8 +10,8 @@
 12233	Sources/GhosttyTerminalView.swift
 11592	Sources/Panels/BrowserPanel.swift
 9497	cmuxTests/CLINotifyProcessIntegrationRegressionTests.swift
+8046	Sources/Panels/BrowserPanelView.swift
 8016	CLI/cmux_open.swift
-7982	Sources/Panels/BrowserPanelView.swift
 7366	cmuxTests/WorkspaceUnitTests.swift
 7218	cmuxTests/WorkspaceRemoteConnectionTests.swift
 6895	Packages/iOS/CmuxMobileShell/Sources/CmuxMobileShell/MobileShellComposite.swift
@@ -24,7 +24,7 @@
 4487	Sources/Panels/FilePreviewPanel.swift
 4476	Sources/cmuxApp.swift
 4367	cmuxTests/BrowserPanelTests.swift
-4133	Sources/BrowserWindowPortal.swift
+4121	Sources/BrowserWindowPortal.swift
 3934	Sources/Feed/FeedPanelView.swift
 3926	cmuxTests/TabManagerUnitTests.swift
 3896	cmuxTests/WindowAndDragTests.swift
@@ -42,7 +42,7 @@
 2395	Sources/Mobile/MobileHostService.swift
 2328	cmuxTests/CJKIMEInputTests.swift
 2242	Sources/TerminalNotificationStore.swift
-2233	Sources/TerminalWindowPortal.swift
+2231	Sources/TerminalWindowPortal.swift
 2126	cmuxTests/CmuxConfigTests.swift
 2091	cmuxTests/ShortcutAndCommandPaletteTests.swift
 2078	Sources/SessionPersistence.swift

Sources/BrowserWindowPortal.swift

@@ -818,10 +818,18 @@ final class WindowBrowserHostView: NSView {
         at point: NSPoint,
         visibleSlots: [WindowBrowserSlotView]
     ) -> Bool {
-        guard let rightMostEdge = visibleSlots.map(\.frame.maxX).max() else { return false }
-        let trailingGap = bounds.maxX - rightMostEdge
+        let dockDividerX = visibleSlots
+            .filter { $0.isRightSidebarDockSlot }
+            .map(\.frame.minX)
+            .min()
+        let contentRightEdge = visibleSlots
+            .filter { !$0.isRightSidebarDockSlot }
+            .map(\.frame.maxX)
+            .max()
+        guard let dividerX = dockDividerX ?? contentRightEdge else { return false }
+        let trailingGap = bounds.maxX - dividerX
         guard trailingGap > Self.minimumVisibleLeadingContentWidth else { return false }
-        return SidebarResizeInteraction.Edge.trailing.hitRange(dividerX: rightMostEdge).contains(point.x)
+        return SidebarResizeInteraction.Edge.trailing.hitRange(dividerX: dividerX).contains(point.x)
     }
 
     private func updateDividerCursor(
@@ -1155,11 +1163,9 @@ final class WindowBrowserHostView: NSView {
     }
 
     private static func dividerHit(at windowPoint: NSPoint, in regions: [DividerRegion], checkLiveness: Bool = true) -> DividerHit? {
-        let expansion: CGFloat = 5
         for region in regions.reversed() {
             if checkLiveness, !region.isLive { continue }
-            let hitRect = region.rectInWindow.insetBy(dx: -expansion, dy: -expansion)
-                .intersection(region.boundsInWindow)
+            let hitRect = region.hitRectInWindow
             if !hitRect.isNull, hitRect.contains(windowPoint) {
                 return DividerHit(
                     kind: region.isVertical ? .vertical : .horizontal,
@@ -1313,6 +1319,7 @@ final class WindowBrowserSlotView: NSView {
     private var paneTopChromeHeight: CGFloat = 0
     var preferredHostedInspectorWidth: CGFloat?
     private var preferredHostedInspectorWidthFraction: CGFloat?
+    fileprivate var isRightSidebarDockSlot = false
     fileprivate var isHostedInspectorDividerDragActive = false
     var onHostedInspectorLayout: ((WindowBrowserSlotView) -> Void)?
     fileprivate var isApplyingHostedInspectorLayout = false
@@ -1400,6 +1407,7 @@ final class WindowBrowserSlotView: NSView {
 
     func setPaneDropContext(_ context: BrowserPaneDropContext?) {
         paneDropTargetView.dropContext = context
+        isRightSidebarDockSlot = context.map { AppDelegate.shared?.dockForPane($0.paneId) != nil } ?? false
     }
 
     var currentPaneDropContext: BrowserPaneDropContext? {
@@ -1974,30 +1982,10 @@ final class WindowBrowserPortal: NSObject {
         guard splitView.arrangedSubviews.count >= 2 else { return }
 
         let location = splitView.convert(event.locationInWindow, from: nil)
-        let first = splitView.arrangedSubviews[0].frame
-        let second = splitView.arrangedSubviews[1].frame
-        let thickness = splitView.dividerThickness
-        let dividerRect: NSRect
-
-        if splitView.isVertical {
-            guard first.width > 1, second.width > 1 else { return }
-            dividerRect = NSRect(
-                x: max(0, first.maxX),
-                y: 0,
-                width: thickness,
-                height: splitView.bounds.height
-            )
-        } else {
-            guard first.height > 1, second.height > 1 else { return }
-            dividerRect = NSRect(
-                x: 0,
-                y: max(0, first.maxY),
-                width: splitView.bounds.width,
-                height: thickness
-            )
-        }
-
-        let hitRect = dividerRect.insetBy(dx: -5, dy: -5)
+        guard let hitRect = PortalSplitDividerRegion.dividerHitRect(
+            in: splitView,
+            dividerIndex: 0
+        ) else { return }
         if dividerHitRectContains(location, rect: hitRect) {
             window.browserPortalHasInteractiveSplitDividerDrag = true
         }

Sources/Panels/BrowserPanelView.swift

@@ -6486,6 +6486,12 @@ struct WebViewRepresentable: NSViewRepresentable {
             if passThrough {
 #if DEBUG
                 debugLogHitTest(stage: "hitTest.pass", point: point, passThrough: true, hitView: nil)
+#endif
+                return nil
+            }
+            if shouldPassThroughToExternalSplitDivider(at: point, hostedInspectorHit: hostedInspectorHit) {
+#if DEBUG
+                debugLogHitTest(stage: "hitTest.splitPass", point: point, passThrough: true, hitView: nil)
 #endif
                 return nil
             }
@@ -6646,6 +6652,60 @@ struct WebViewRepresentable: NSViewRepresentable {
             return contentView.bounds.maxX - hostRectInContent.maxX > 24
         }
 
+        private func shouldPassThroughToExternalSplitDivider(
+            at point: NSPoint,
+            hostedInspectorHit: HostedInspectorDividerHit? = nil
+        ) -> Bool {
+            guard hostedInspectorHit == nil else { return false }
+            guard isNearPaneEdge(point) else { return false }
+            guard window != nil else { return false }
+
+            let windowPoint = convert(point, to: nil)
+            var ancestor = superview
+            while let currentAncestor = ancestor {
+                if let splitView = currentAncestor as? NSSplitView,
+                   let arrangedIndex = splitView.arrangedSubviews.firstIndex(where: { arrangedSubview in
+                       self === arrangedSubview || self.isDescendant(of: arrangedSubview)
+                   }) {
+                    if externalSplitDividerHit(at: windowPoint, in: splitView, dividerIndex: arrangedIndex - 1) {
+                        return true
+                    }
+                    if externalSplitDividerHit(at: windowPoint, in: splitView, dividerIndex: arrangedIndex) {
+                        return true
+                    }
+                }
+                ancestor = currentAncestor.superview
+            }
+            return false
+        }
+
+        private func externalSplitDividerHit(
+            at windowPoint: NSPoint,
+            in splitView: NSSplitView,
+            dividerIndex: Int
+        ) -> Bool {
+            guard let window,
+                  splitView.window === window,
+                  let hitRect = PortalSplitDividerRegion.dividerHitRectInWindow(
+                      in: splitView,
+                      dividerIndex: dividerIndex
+                  ) else {
+                return false
+            }
+            return hitRect.contains(windowPoint)
+        }
+
+        private func isNearPaneEdge(_ point: NSPoint) -> Bool {
+            // hitTest and cursor tracking call this with points in this view's bounds coordinates.
+            guard bounds.contains(point) else { return false }
+            let expansion = PortalSplitDividerRegion.dividerHitExpansion
+            let nearVerticalEdge = point.x <= bounds.minX + expansion ||
+                point.x >= bounds.maxX - expansion
+            let nearHorizontalEdge = point.y <= bounds.minY + expansion ||
+                point.y >= bounds.maxY - expansion
+            return nearVerticalEdge || nearHorizontalEdge
+        }
+
         private func updateDividerCursor(
             at point: NSPoint,
             hostedInspectorHit: HostedInspectorDividerHit? = nil
@@ -6655,6 +6715,10 @@ struct WebViewRepresentable: NSViewRepresentable {
                 clearActiveDividerCursor(restoreArrow: false)
                 return
             }
+            if shouldPassThroughToExternalSplitDivider(at: point, hostedInspectorHit: resolvedHostedInspectorHit) {
+                clearActiveDividerCursor(restoreArrow: false)
+                return
+            }
             guard resolvedHostedInspectorHit != nil else {
                 clearActiveDividerCursor(restoreArrow: true)
                 return

Sources/PortalSplitDividerRegion.swift

@@ -10,6 +10,8 @@ final class PortalSplitDividerRegion {
     let isVertical: Bool
     let isInHostedContent: Bool
 
+    static let dividerHitExpansion: CGFloat = 5
+
     init(
         splitView: NSSplitView,
         dividerIndex: Int,
@@ -52,6 +54,44 @@ final class PortalSplitDividerRegion {
         regions.allSatisfy(\.isLive)
     }
 
+    var hitRectInWindow: NSRect {
+        rectInWindow
+            .insetBy(dx: -Self.dividerHitExpansion, dy: -Self.dividerHitExpansion)
+            .intersection(boundsInWindow)
+    }
+
+    static func dividerRect(in splitView: NSSplitView, dividerIndex: Int) -> NSRect? {
+        guard dividerIndex >= 0,
+              dividerIndex + 1 < splitView.arrangedSubviews.count else {
+            return nil
+        }
+
+        let first = splitView.arrangedSubviews[dividerIndex].frame
+        let second = splitView.arrangedSubviews[dividerIndex + 1].frame
+        let thickness = splitView.dividerThickness
+        if splitView.isVertical {
+            guard first.width > 1 || second.width > 1 else { return nil }
+            return NSRect(x: max(0, first.maxX), y: 0, width: thickness, height: splitView.bounds.height)
+        }
+
+        guard first.height > 1 || second.height > 1 else { return nil }
+        return NSRect(x: 0, y: max(0, first.maxY), width: splitView.bounds.width, height: thickness)
+    }
+
+    static func dividerHitRect(in splitView: NSSplitView, dividerIndex: Int) -> NSRect? {
+        guard let dividerRect = dividerRect(in: splitView, dividerIndex: dividerIndex) else { return nil }
+        return dividerRect
+            .insetBy(dx: -Self.dividerHitExpansion, dy: -Self.dividerHitExpansion)
+            .intersection(splitView.bounds)
+    }
+
+    static func dividerHitRectInWindow(in splitView: NSSplitView, dividerIndex: Int) -> NSRect? {
+        guard let hitRect = dividerHitRect(in: splitView, dividerIndex: dividerIndex) else { return nil }
+        let hitRectInWindow = splitView.convert(hitRect, to: nil)
+        guard hitRectInWindow.width > 0, hitRectInWindow.height > 0 else { return nil }
+        return hitRectInWindow
+    }
+
     static func collect(
         in rootView: NSView,
         hostView: NSView? = nil
@@ -142,19 +182,7 @@ final class PortalSplitDividerRegion {
         let splitBoundsInWindow = splitView.convert(splitView.bounds, to: nil)
         let dividerCount = max(0, splitView.arrangedSubviews.count - 1)
         for dividerIndex in 0..<dividerCount {
-            let first = splitView.arrangedSubviews[dividerIndex].frame
-            let second = splitView.arrangedSubviews[dividerIndex + 1].frame
-            let thickness = splitView.dividerThickness
-            let dividerRect: NSRect
-            if splitView.isVertical {
-                guard first.width > 1 || second.width > 1 else { continue }
-                let x = max(0, first.maxX)
-                dividerRect = NSRect(x: x, y: 0, width: thickness, height: splitView.bounds.height)
-            } else {
-                guard first.height > 1 || second.height > 1 else { continue }
-                let y = max(0, first.maxY)
-                dividerRect = NSRect(x: 0, y: y, width: splitView.bounds.width, height: thickness)
-            }
+            guard let dividerRect = dividerRect(in: splitView, dividerIndex: dividerIndex) else { continue }
             let dividerRectInWindow = splitView.convert(dividerRect, to: nil)
             guard dividerRectInWindow.width > 0, dividerRectInWindow.height > 0 else { continue }
             result.append(PortalSplitDividerRegion(

Sources/TerminalWindowPortal.swift

@@ -417,11 +417,9 @@ final class WindowTerminalHostView: NSView {
     }
 
     private static func dividerCursorKind(at windowPoint: NSPoint, in regions: [DividerRegion], checkLiveness: Bool = true) -> DividerCursorKind? {
-        let expansion: CGFloat = 5
         for region in regions.reversed() {
             if checkLiveness, !region.isLive { continue }
-            let hitRect = region.rectInWindow.insetBy(dx: -expansion, dy: -expansion)
-                .intersection(region.boundsInWindow)
+            let hitRect = region.hitRectInWindow
             if !hitRect.isNull, hitRect.contains(windowPoint) {
                 return region.isVertical ? .vertical : .horizontal
             }