lawrencecchen · Mar 13, 2026 · Mar 13, 2026 · Mar 13, 2026 · Mar 13, 2026 · Mar 13, 2026
diff --git a/Resources/Localizable.xcstrings b/Resources/Localizable.xcstrings
@@ -27859,6 +27859,57 @@
         }
       }
     },
+    "dialog.closeWorkspaces.message": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "This will close %1$lld workspaces and all of their panels:\n%2$@"
+          }
+        },
+        "ja": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "%1$lld 個のワークスペースと、それぞれのすべてのパネルを閉じます:\n%2$@"
+          }
+        }
+      }
+    },
+    "dialog.closeWorkspaces.title": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "Close workspaces?"
+          }
+        },
+        "ja": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "ワークスペースを閉じますか？"
+          }
+        }
+      }
+    },
+    "dialog.closeWorkspacesWindow.message": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "This will close the current window, its %1$lld workspaces, and all of their panels:\n%2$@"
+          }
+        },
+        "ja": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "現在のウィンドウと、その %1$lld 個のワークスペースと、それぞれのすべてのパネルを閉じます:\n%2$@"
+          }
+        }
+      }
+    },
     "dialog.closeWorkspace.message": {
       "extractionState": "manual",
       "localizations": {

diff --git a/Sources/AppDelegate.swift b/Sources/AppDelegate.swift
@@ -7741,6 +7741,7 @@ final class AppDelegate: NSObject, NSApplicationDelegate, UNUserNotificationCent
         // equivalents working and avoid surprising actions while the confirmation is up.
         let closeConfirmationTitles = [
             String(localized: "dialog.closeWorkspace.title", defaultValue: "Close workspace?"),
+            String(localized: "dialog.closeWorkspaces.title", defaultValue: "Close workspaces?"),
             String(localized: "dialog.closeTab.title", defaultValue: "Close tab?"),
             String(localized: "dialog.closeOtherTabs.title", defaultValue: "Close other tabs?"),
             String(localized: "dialog.closeWindow.title", defaultValue: "Close window?"),

diff --git a/Sources/ContentView.swift b/Sources/ContentView.swift
@@ -1330,6 +1330,7 @@ struct ContentView: View {
     @State private var retiringWorkspaceId: UUID?
     @State private var workspaceHandoffGeneration: UInt64 = 0
     @State private var workspaceHandoffFallbackTask: Task<Void, Never>?
+    @State private var didApplyUITestSidebarSelection = false
     @State private var titlebarThemeGeneration: UInt64 = 0
     @State private var sidebarDraggedTabId: UUID?
     @State private var titlebarTextUpdateCoalescer = NotificationBurstCoalescer(delay: 1.0 / 30.0)
@@ -2233,6 +2234,8 @@ struct ContentView: View {
                 selectedTabIds = [selectedId]
                 lastSidebarSelectionIndex = tabManager.tabs.firstIndex { $0.id == selectedId }
             }
+            syncSidebarSelectedWorkspaceIds()
+            applyUITestSidebarSelectionIfNeeded(tabs: tabManager.tabs)
             updateTitlebarText()
 
             // Startup recovery (#399): if session restore or a race condition leaves the
@@ -2267,6 +2270,9 @@ struct ContentView: View {
                     didRecover = true
                 }
 
+                syncSidebarSelectedWorkspaceIds()
+                applyUITestSidebarSelectionIfNeeded(tabs: tabManager.tabs)
+
                 if didRecover {
 #if DEBUG
                     dlog("startup.recovery tabCount=\(tabManager.tabs.count) selected=\(tabManager.selectedTabId?.uuidString.prefix(8) ?? "nil") mounted=\(mountedWorkspaceIds.count)")
@@ -2302,6 +2308,10 @@ struct ContentView: View {
             updateTitlebarText()
         })
 
+        view = AnyView(view.onChange(of: selectedTabIds) { _ in
+            syncSidebarSelectedWorkspaceIds()
+        })
+
         view = AnyView(view.onChange(of: tabManager.isWorkspaceCycleHot) { _ in
 #if DEBUG
             if let snapshot = tabManager.debugCurrentWorkspaceSwitchSnapshot() {
@@ -2401,6 +2411,8 @@ struct ContentView: View {
                     lastSidebarSelectionIndex = nil
                 }
             }
+            syncSidebarSelectedWorkspaceIds()
+            applyUITestSidebarSelectionIfNeeded(tabs: tabs)
         })
 
         view = AnyView(view.onReceive(NotificationCenter.default.publisher(for: SidebarDragLifecycleNotification.stateDidChange)) { notification in
@@ -5962,11 +5974,7 @@ struct ContentView: View {
     }
 
     private func closeWorkspaceIds(_ workspaceIds: [UUID], allowPinned: Bool) {
-        for workspaceId in workspaceIds {
-            guard let workspace = tabManager.tabs.first(where: { $0.id == workspaceId }) else { continue }
-            guard allowPinned || !workspace.isPinned else { continue }
-            tabManager.closeWorkspaceWithConfirmation(workspace)
-        }
+        tabManager.closeWorkspacesWithConfirmation(workspaceIds, allowPinned: allowPinned)
     }
 
     private func closeOtherSelectedWorkspaces() {
@@ -5976,19 +5984,53 @@ struct ContentView: View {
     }
 
     private func closeSelectedWorkspacesBelow() {
-        guard let workspace = tabManager.selectedWorkspace,
+        guard tabManager.selectedWorkspace != nil,
               let anchorIndex = selectedWorkspaceIndex() else { return }
         let workspaceIds = tabManager.tabs.suffix(from: anchorIndex + 1).map(\.id)
         closeWorkspaceIds(workspaceIds, allowPinned: false)
     }
 
     private func closeSelectedWorkspacesAbove() {
-        guard let workspace = tabManager.selectedWorkspace,
+        guard tabManager.selectedWorkspace != nil,
               let anchorIndex = selectedWorkspaceIndex() else { return }
         let workspaceIds = tabManager.tabs.prefix(upTo: anchorIndex).map(\.id)
         closeWorkspaceIds(workspaceIds, allowPinned: false)
     }
 
+    private func syncSidebarSelectedWorkspaceIds() {
+        tabManager.setSidebarSelectedWorkspaceIds(selectedTabIds)
+    }
+
+    private func applyUITestSidebarSelectionIfNeeded(tabs: [Workspace]) {
+#if DEBUG
+        guard !didApplyUITestSidebarSelection else { return }
+        let env = ProcessInfo.processInfo.environment
+        guard let rawValue = env["CMUX_UI_TEST_SIDEBAR_SELECTED_WORKSPACE_INDICES"]?
+            .trimmingCharacters(in: .whitespacesAndNewlines),
+              !rawValue.isEmpty else {
+            return
+        }
+
+        var indices: [Int] = []
+        for token in rawValue.split(separator: ",") {
+            let trimmed = token.trimmingCharacters(in: .whitespacesAndNewlines)
+            guard let index = Int(trimmed), index >= 0 else { return }
+            if !indices.contains(index) {
+                indices.append(index)
+            }
+        }
+
+        guard let lastIndex = indices.last, !indices.isEmpty, lastIndex < tabs.count else { return }
+
+        let selectedIds = Set(indices.map { tabs[$0].id })
+        selectedTabIds = selectedIds
+        lastSidebarSelectionIndex = lastIndex
+        tabManager.selectWorkspace(tabs[lastIndex])
+        sidebarSelectionState.selection = .tabs
+        didApplyUITestSidebarSelection = true
+#endif
+    }
+
     private func beginRenameWorkspaceFlow() {
         guard let workspace = tabManager.selectedWorkspace else {
             NSSound.beep()
@@ -10289,16 +10331,7 @@ private struct TabItemView: View, Equatable {
     }
 
     private func closeTabs(_ targetIds: [UUID], allowPinned: Bool) {
-        let idsToClose = targetIds.filter { id in
-            guard let tab = tabManager.tabs.first(where: { $0.id == id }) else { return false }
-            return allowPinned || !tab.isPinned
-        }
-        for id in idsToClose {
-            if let tab = tabManager.tabs.first(where: { $0.id == id }) {
-                tabManager.closeWorkspaceWithConfirmation(tab)
-            }
-        }
-        selectedTabIds.subtract(idsToClose)
+        tabManager.closeWorkspacesWithConfirmation(targetIds, allowPinned: allowPinned)
         syncSelectionAfterMutation()
     }
 

diff --git a/Sources/TabManager.swift b/Sources/TabManager.swift
@@ -713,6 +713,8 @@ class TabManager: ObservableObject {
     private var workspaceCycleGeneration: UInt64 = 0
     private var workspaceCycleCooldownTask: Task<Void, Never>?
     private var pendingWorkspaceUnfocusTarget: (tabId: UUID, panelId: UUID)?
+    private var sidebarSelectedWorkspaceIds: Set<UUID> = []
+    var confirmCloseHandler: ((String, String, Bool) -> Bool)?
 #if DEBUG
     private var debugWorkspaceSwitchCounter: UInt64 = 0
     private var debugWorkspaceSwitchId: UInt64 = 0
@@ -1338,6 +1340,7 @@ class TabManager: ObservableObject {
         guard let index = tabs.firstIndex(where: { $0.id == workspace.id }) else { return }
         sentryBreadcrumb("workspace.close", data: ["tabCount": tabs.count - 1])
         clearInitialWorkspaceGitProbe(workspaceId: workspace.id)
+        sidebarSelectedWorkspaceIds.remove(workspace.id)
 
         AppDelegate.shared?.notificationStore?.clearNotifications(forTabId: workspace.id)
         unwireClosedBrowserTracking(for: workspace)
@@ -1360,6 +1363,7 @@ class TabManager: ObservableObject {
     func detachWorkspace(tabId: UUID) -> Workspace? {
         guard let index = tabs.firstIndex(where: { $0.id == tabId }) else { return nil }
         clearInitialWorkspaceGitProbe(workspaceId: tabId)
+        sidebarSelectedWorkspaceIds.remove(tabId)
 
         let removed = tabs.remove(at: index)
         unwireClosedBrowserTracking(for: removed)
@@ -1441,6 +1445,11 @@ class TabManager: ObservableObject {
 #if DEBUG
         UITestRecorder.incrementInt("closeTabInvocations")
 #endif
+        let sidebarSelectionIds = orderedSidebarSelectedWorkspaceIds()
+        if sidebarSelectionIds.count > 1 {
+            closeWorkspacesWithConfirmation(sidebarSelectionIds, allowPinned: true)
+            return
+        }
         guard let selectedId = selectedTabId,
               let workspace = tabs.first(where: { $0.id == selectedId }) else { return }
         closeWorkspaceWithConfirmation(workspace)
@@ -1455,6 +1464,32 @@ class TabManager: ObservableObject {
         closeWorkspaceWithConfirmation(workspace)
     }
 
+    func setSidebarSelectedWorkspaceIds(_ workspaceIds: Set<UUID>) {
+        let existingIds = Set(tabs.map(\.id))
+        sidebarSelectedWorkspaceIds = workspaceIds.intersection(existingIds)
+    }
+
+    func closeWorkspacesWithConfirmation(_ workspaceIds: [UUID], allowPinned: Bool) {
+        let workspaces = orderedClosableWorkspaces(workspaceIds, allowPinned: allowPinned)
+        guard !workspaces.isEmpty else { return }
+        guard workspaces.count > 1 else {
+            closeWorkspaceWithConfirmation(workspaces[0])
+            return
+        }
+
+        let plan = closeWorkspacesPlan(for: workspaces)
+        guard confirmClose(
+            title: plan.title,
+            message: plan.message,
+            acceptCmdD: plan.acceptCmdD
+        ) else { return }
+
+        for workspace in plan.workspaces {
+            guard tabs.contains(where: { $0.id == workspace.id }) else { continue }
+            closeWorkspaceIfRunningProcess(workspace, requiresConfirmation: false)
+        }
+    }
+
     func selectWorkspace(_ workspace: Workspace) {
         selectedTabId = workspace.id
     }
@@ -1463,6 +1498,10 @@ class TabManager: ObservableObject {
     func selectTab(_ tab: Workspace) { selectWorkspace(tab) }
 
     private func confirmClose(title: String, message: String, acceptCmdD: Bool) -> Bool {
+        if let confirmCloseHandler {
+            return confirmCloseHandler(title, message, acceptCmdD)
+        }
+
         let alert = NSAlert()
         alert.messageText = title
         alert.informativeText = message
@@ -1490,6 +1529,13 @@ class TabManager: ObservableObject {
         let titles: [String]
     }
 
+    private struct CloseWorkspacesPlan {
+        let workspaces: [Workspace]
+        let title: String
+        let message: String
+        let acceptCmdD: Bool
+    }
+
     private func closeOtherTabsInFocusedPanePlan() -> CloseOtherTabsInFocusedPanePlan? {
         guard let workspace = selectedWorkspace else { return nil }
         guard let paneId = workspace.bonsplitController.focusedPaneId ?? workspace.bonsplitController.allPaneIds.first else {
@@ -1532,9 +1578,62 @@ class TabManager: ObservableObject {
         return String(localized: "tab.untitled", defaultValue: "Untitled Tab")
     }
 
-    private func closeWorkspaceIfRunningProcess(_ workspace: Workspace) {
+    private func orderedClosableWorkspaces(_ workspaceIds: [UUID], allowPinned: Bool) -> [Workspace] {
+        let targetIds = Set(workspaceIds)
+        return tabs.compactMap { workspace in
+            guard targetIds.contains(workspace.id) else { return nil }
+            guard allowPinned || !workspace.isPinned else { return nil }
+            return workspace
+        }
+    }
+
+    private func orderedSidebarSelectedWorkspaceIds() -> [UUID] {
+        tabs.compactMap { workspace in
+            sidebarSelectedWorkspaceIds.contains(workspace.id) ? workspace.id : nil
+        }
+    }
+
+    private func closeWorkspacesPlan(for workspaces: [Workspace]) -> CloseWorkspacesPlan {
+        let willCloseWindow = workspaces.count == tabs.count
+        let title = willCloseWindow
+            ? String(localized: "dialog.closeWindow.title", defaultValue: "Close window?")
+            : String(localized: "dialog.closeWorkspaces.title", defaultValue: "Close workspaces?")
+        let titleLines = workspaces
+            .map { "• \(closeWorkspaceDisplayTitle($0.title))" }
+            .joined(separator: "\n")
+        let format = willCloseWindow
+            ? String(
+                localized: "dialog.closeWorkspacesWindow.message",
+                defaultValue: "This will close the current window, its %1$lld workspaces, and all of their panels:\n%2$@"
+            )
+            : String(
+                localized: "dialog.closeWorkspaces.message",
+                defaultValue: "This will close %1$lld workspaces and all of their panels:\n%2$@"
+            )
+        let message = String(format: format, locale: .current, Int64(workspaces.count), titleLines)
+        return CloseWorkspacesPlan(
+            workspaces: workspaces,
+            title: title,
+            message: message,
+            acceptCmdD: willCloseWindow
+        )
+    }
+
+    private func closeWorkspaceDisplayTitle(_ title: String?) -> String {
+        let collapsed = title?
+            .replacingOccurrences(of: "\n", with: " ")
+            .replacingOccurrences(of: "\r", with: " ")
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+        if let collapsed, !collapsed.isEmpty {
+            return collapsed
+        }
+        return String(localized: "workspace.displayName.fallback", defaultValue: "Workspace")
+    }
+
+    private func closeWorkspaceIfRunningProcess(_ workspace: Workspace, requiresConfirmation: Bool = true) {
         let willCloseWindow = tabs.count <= 1
-        if workspaceNeedsConfirmClose(workspace),
+        if requiresConfirmation,
+           workspaceNeedsConfirmClose(workspace),
            !confirmClose(
                title: String(localized: "dialog.closeWorkspace.title", defaultValue: "Close workspace?"),
                message: String(localized: "dialog.closeWorkspace.message", defaultValue: "This will close the workspace and all of its panels."),

diff --git a/Sources/cmuxApp.swift b/Sources/cmuxApp.swift
@@ -881,11 +881,7 @@ struct cmuxApp: App {
         in manager: TabManager,
         allowPinned: Bool
     ) {
-        for workspaceId in workspaceIds {
-            guard let workspace = manager.tabs.first(where: { $0.id == workspaceId }) else { continue }
-            guard allowPinned || !workspace.isPinned else { continue }
-            manager.closeWorkspaceWithConfirmation(workspace)
-        }
+        manager.closeWorkspacesWithConfirmation(workspaceIds, allowPinned: allowPinned)
     }
 
     private func closeOtherSelectedWorkspacePeers(in manager: TabManager) {