Merge branch 'feature/running-apps'

RunningApps maps installed casks to their .app bundles via the
Caskroom copy (no brew process needed) and checks them against
NSWorkspace's running applications. Two settings in a new "Running
apps" section: auto-upgrade skips running casks (on by default —
that flow has no dialog to warn anyone), manual bulk upgrades can opt
in. The auto-upgrade filter runs before the trigger decision so a
permanently running app cannot start an upgrade cycle that would skip
it anyway. The confirmation dialog now names the apps actually
running instead of a blanket warning, and stays silent when none are.
Single-package upgrades from the Outdated menu always proceed.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

BrewBar/BrewBarApp.swift

@@ -363,7 +363,14 @@ class AppDelegate: NSObject, NSApplicationDelegate {
             // packages that turn outdated only after this brew update are not
             // in cachedOutdated yet; the final refetch will surface them
             let formulaNames = formulae ? self.cachedOutdated.formulae.map(\.name) : []
-            let caskNames = casks ? self.cachedOutdated.casks.map(\.name) : []
+            var caskNames = casks ? self.cachedOutdated.casks.map(\.name) : []
+            if Settings.skipRunningCasksManual, !caskNames.isEmpty {
+                let running = RunningApps.runningCasks(caskNames, brewPath: self.resolveBrewPath())
+                if !running.isEmpty {
+                    self.log("upgrade: skipping running app\(running.count == 1 ? "" : "s"): \(running.joined(separator: ", "))\n")
+                    caskNames.removeAll(where: running.contains)
+                }
+            }
 
             self.upgradeFormulaeSequentially(formulaNames) {
                 self.upgradeCasksSequentially(caskNames) {
@@ -443,10 +450,18 @@ class AppDelegate: NSObject, NSApplicationDelegate {
             alert.messageText = "Upgrade \(packages.count) package\(packages.count == 1 ? "" : "s")?"
         }
 
-        // the running-app warning only applies when casks are being upgraded
+        // warn only about apps that are actually running right now, by name
         var lines: [String] = []
         if casks {
-            lines.append("Apps upgraded as casks (like a web browser) may be closed and replaced while running, without further warning. Save your work first.")
+            let running = RunningApps.runningCasks(cachedOutdated.casks.map(\.name), brewPath: resolveBrewPath())
+            if !running.isEmpty {
+                let list = running.joined(separator: ", ")
+                if Settings.skipRunningCasksManual {
+                    lines.append("Currently running, will be skipped: \(list).")
+                } else {
+                    lines.append("Currently running: \(list). These apps may be closed and replaced mid-use, without further warning. Save your work first.")
+                }
+            }
         }
         if !packages.isEmpty {
             lines.append(packages.map(\.label).joined(separator: "\n"))
@@ -492,9 +507,18 @@ class AppDelegate: NSObject, NSApplicationDelegate {
             // only trigger for the kinds that are both enabled AND outdated —
             // e.g. an outdated cask must not start a pointless formulae upgrade
             let upgradeFormulae = Settings.autoUpgradeFormulae && !outdated.formulae.isEmpty
-            let upgradeCasks = Settings.autoUpgradeCasks && !outdated.casks.isEmpty
-            if allowAutoUpgrade, upgradeFormulae || upgradeCasks {
-                self.runAutoUpgrade(formulae: upgradeFormulae, casks: upgradeCasks)
+            var autoCaskNames = Settings.autoUpgradeCasks ? outdated.casks.map(\.name) : []
+            // filtered before the trigger decision: a permanently running app
+            // must not start an upgrade cycle that would skip it anyway
+            if Settings.skipRunningCasksAuto, !autoCaskNames.isEmpty {
+                let running = RunningApps.runningCasks(autoCaskNames, brewPath: self.resolveBrewPath())
+                if !running.isEmpty {
+                    self.log("auto-upgrade: skipping running app\(running.count == 1 ? "" : "s"): \(running.joined(separator: ", "))\n")
+                    autoCaskNames.removeAll(where: running.contains)
+                }
+            }
+            if allowAutoUpgrade, upgradeFormulae || !autoCaskNames.isEmpty {
+                self.runAutoUpgrade(formulae: upgradeFormulae, caskNames: autoCaskNames)
                 return
             }
 
@@ -526,13 +550,12 @@ class AppDelegate: NSObject, NSApplicationDelegate {
         UNUserNotificationCenter.current().add(request)
     }
 
-    func runAutoUpgrade(formulae: Bool, casks: Bool) {
+    func runAutoUpgrade(formulae: Bool, caskNames: [String]) {
         statusMenuItem.title = "Auto-upgrading..."
         setMenuBarIcon("brewbar-updating")
         failedUpgrades = []
 
         let formulaNames = formulae ? cachedOutdated.formulae.map(\.name) : []
-        let caskNames = casks ? cachedOutdated.casks.map(\.name) : []
 
         upgradeFormulaeSequentially(formulaNames) {
             self.upgradeCasksSequentially(caskNames) {

BrewBar/RunningApps.swift

@@ -0,0 +1,46 @@
+import AppKit
+
+/// Maps installed casks to their .app bundles and checks them against the
+/// apps currently running. The mapping comes from the Caskroom: brew keeps
+/// a copy of every installed cask's artifacts there, so listing
+/// <prefix>/Caskroom/<token>/<version>/*.app gives the app names without
+/// spawning a brew process.
+enum RunningApps {
+    /// Caskroom lives next to the brew binary: <prefix>/bin/brew → <prefix>/Caskroom
+    static func caskroomURL(brewPath: String) -> URL {
+        URL(fileURLWithPath: brewPath)
+            .deletingLastPathComponent() // <prefix>/bin
+            .deletingLastPathComponent() // <prefix>
+            .appendingPathComponent("Caskroom", isDirectory: true)
+    }
+
+    /// .app bundle names (e.g. "Firefox.app") found in any installed version
+    /// of the cask. Casks without an app artifact (fonts, pkg-based
+    /// installers) return [] and are never considered running.
+    static func appNames(forCask token: String, brewPath: String) -> [String] {
+        let caskDir = caskroomURL(brewPath: brewPath).appendingPathComponent(token, isDirectory: true)
+        let fm = FileManager.default
+        guard let versions = try? fm.contentsOfDirectory(atPath: caskDir.path) else { return [] }
+
+        var names: Set<String> = []
+        for version in versions where !version.hasPrefix(".") {
+            let versionDir = caskDir.appendingPathComponent(version, isDirectory: true)
+            for entry in (try? fm.contentsOfDirectory(atPath: versionDir.path)) ?? [] where entry.hasSuffix(".app") {
+                names.insert(entry)
+            }
+        }
+        return Array(names)
+    }
+
+    /// Subset of the given cask tokens whose app is currently running.
+    /// Matches on the bundle name — the running copy lives in /Applications,
+    /// the Caskroom one is brew's, but both carry the same name.
+    static func runningCasks(_ tokens: [String], brewPath: String) -> [String] {
+        let running = Set(NSWorkspace.shared.runningApplications.compactMap {
+            $0.bundleURL?.lastPathComponent
+        })
+        return tokens.filter { token in
+            appNames(forCask: token, brewPath: brewPath).contains { running.contains($0) }
+        }
+    }
+}

BrewBar/Settings.swift

@@ -12,6 +12,7 @@ enum Settings {
         UserDefaults.standard.register(defaults: [
             "includeGreedyCasks": true,
             "confirmBeforeUpgradeAll": true,
+            "skipRunningCasksAuto": true,
         ])
     }
 
@@ -49,4 +50,18 @@ enum Settings {
         get { UserDefaults.standard.bool(forKey: "cleanupAfterUpgrade") }
         set { UserDefaults.standard.set(newValue, forKey: "cleanupAfterUpgrade") }
     }
+
+    /// auto-upgrade never touches a cask whose app is running (on by default:
+    /// there is no dialog to warn anyone in that flow)
+    static var skipRunningCasksAuto: Bool {
+        get { UserDefaults.standard.bool(forKey: "skipRunningCasksAuto") }
+        set { UserDefaults.standard.set(newValue, forKey: "skipRunningCasksAuto") }
+    }
+
+    /// manual bulk upgrades skip running apps too (off by default: the
+    /// confirmation dialog already names them)
+    static var skipRunningCasksManual: Bool {
+        get { UserDefaults.standard.bool(forKey: "skipRunningCasksManual") }
+        set { UserDefaults.standard.set(newValue, forKey: "skipRunningCasksManual") }
+    }
 }

BrewBar/SettingsWindowController.swift

@@ -23,6 +23,8 @@ class SettingsWindowController: NSWindowController {
     var showCountCheckbox: NSButton!
     var confirmCheckbox: NSButton!
     var cleanupCheckbox: NSButton!
+    var skipRunningAutoCheckbox: NSButton!
+    var skipRunningManualCheckbox: NSButton!
 
     convenience init(appDelegate: AppDelegate) {
         let window = NSWindow(
@@ -108,6 +110,26 @@ class SettingsWindowController: NSWindowController {
             "⚠️ Upgrading a cask can close and replace the app while it is running (e.g. your browser), without warning."
         )
 
+        let runningAppsHeader = NSTextField(labelWithString: "Running apps")
+        runningAppsHeader.font = .boldSystemFont(ofSize: NSFont.smallSystemFontSize)
+        runningAppsHeader.textColor = .secondaryLabelColor
+
+        skipRunningAutoCheckbox = NSButton(
+            checkboxWithTitle: "Auto-upgrade: skip casks whose app is running",
+            target: self,
+            action: #selector(toggleSkipRunningAuto(_:))
+        )
+
+        skipRunningManualCheckbox = NSButton(
+            checkboxWithTitle: "Manual upgrades: skip them too",
+            target: self,
+            action: #selector(toggleSkipRunningManual(_:))
+        )
+
+        let runningAppsNote = noteRow(
+            "Skipped apps stay in the outdated list and upgrade at the first check after they quit. Upgrading a single package from the Outdated menu always proceeds."
+        )
+
         notifyCheckbox = NSButton(
             checkboxWithTitle: "Notify when new updates are found",
             target: self,
@@ -142,6 +164,11 @@ class SettingsWindowController: NSWindowController {
             autoUpgradeCasksCheckbox,
             caskWarningRow,
             separator(),
+            runningAppsHeader,
+            skipRunningAutoCheckbox,
+            skipRunningManualCheckbox,
+            runningAppsNote,
+            separator(),
             notifyCheckbox,
             showCountCheckbox,
             confirmCheckbox,
@@ -188,6 +215,8 @@ class SettingsWindowController: NSWindowController {
         showCountCheckbox.state = Settings.showCountInMenuBar ? .on : .off
         confirmCheckbox.state = Settings.confirmBeforeUpgradeAll ? .on : .off
         cleanupCheckbox.state = Settings.cleanupAfterUpgrade ? .on : .off
+        skipRunningAutoCheckbox.state = Settings.skipRunningCasksAuto ? .on : .off
+        skipRunningManualCheckbox.state = Settings.skipRunningCasksManual ? .on : .off
     }
 
     func separator() -> NSBox {
@@ -324,6 +353,14 @@ class SettingsWindowController: NSWindowController {
         Settings.cleanupAfterUpgrade = sender.state == .on
     }
 
+    @objc func toggleSkipRunningAuto(_ sender: NSButton) {
+        Settings.skipRunningCasksAuto = sender.state == .on
+    }
+
+    @objc func toggleSkipRunningManual(_ sender: NSButton) {
+        Settings.skipRunningCasksManual = sender.state == .on
+    }
+
     @objc func toggleLaunchAtLogin(_ sender: NSButton) {
         do {
             if sender.state == .on {

BrewBarTests/BrewBarTests.swift

@@ -1,6 +1,18 @@
 @testable import BrewBar
 import XCTest
 
+final class RunningAppsTests: XCTestCase {
+    func testCaskroomURL_appleSilicon() {
+        let url = RunningApps.caskroomURL(brewPath: "/opt/homebrew/bin/brew")
+        XCTAssertEqual(url.path, "/opt/homebrew/Caskroom")
+    }
+
+    func testCaskroomURL_intel() {
+        let url = RunningApps.caskroomURL(brewPath: "/usr/local/bin/brew")
+        XCTAssertEqual(url.path, "/usr/local/Caskroom")
+    }
+}
+
 final class BrewParserTests: XCTestCase {
     // MARK: - parseOutdatedJSON