feat: improve dealing with reserved/conflicting shortcuts

(closes #3190, closes #3288, closes #1835, closes #3826)

alt-tab-macos.xcodeproj/project.pbxproj

@@ -71,6 +71,7 @@
 		5F4753072CEE5A2E002C6C5E /* AppearanceTestable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8D57C86AF492D43A576D /* AppearanceTestable.swift */; };
 		5F706EC02BA448B1004D542D /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = 5F706EBE2BA448B1004D542D /* Localizable.strings */; };
 		5F706EC32BA448D8004D542D /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = 5F706EC12BA448D8004D542D /* InfoPlist.strings */; };
+		5F882F382EC3C63400110A9F /* CustomRecorderControlTestable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8DC2A355E29516DD2FAF /* CustomRecorderControlTestable.swift */; };
 		76D02BB22BFE7C9E0056008D /* Pods_alt_tab_macos.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C0712B3BEA2B3780398C0999 /* Pods_alt_tab_macos.framework */; };
 		AA974BA929B7D84C0099A29E /* PreviewPanel.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA974BA829B7D84C0099A29E /* PreviewPanel.swift */; };
 		BF0C803A13C409E7F01FBCAB /* SkyLight.framework.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8B94D7994AB9007F6391 /* SkyLight.framework.swift */; };
@@ -129,6 +130,7 @@
 		BF0C86BB79E417163E813179 /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C80851C26EDB3DB98556C /* InfoPlist.strings */; };
 		BF0C875A28B98904F8F4A66A /* ATShortcut.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8BA452332236D972C60E /* ATShortcut.swift */; };
 		BF0C87732A6E660899D13BFD /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C886B1D6E707E9E6BE46C /* InfoPlist.strings */; };
+		BF0C87B5EDCFC573CE220137 /* Helpers.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C89231FD53C4D55E3CF9A /* Helpers.swift */; };
 		BF0C88449007A09F1D175029 /* KeyboardEventsTestable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8643F524515224BF1618 /* KeyboardEventsTestable.swift */; };
 		BF0C8846AFEE2FFF93FAB36F /* AppearanceTestable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8D57C86AF492D43A576D /* AppearanceTestable.swift */; };
 		BF0C884D88B74F05B8BBF956 /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C88A25E1ED37E5F80AC91 /* Localizable.strings */; };
@@ -153,6 +155,7 @@
 		BF0C8A739A74695E60F16369 /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8062E78677398A4A217B /* InfoPlist.strings */; };
 		BF0C8A95AAD9DADC95887A2D /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C895A9AF79A869EE6B108 /* Localizable.strings */; };
 		BF0C8AC57CE5E9BBEEE2442A /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C885D34CDCE2AFC5A94F7 /* InfoPlist.strings */; };
+		BF0C8AD478399D2E97AE3FB4 /* CustomRecorderControlTestable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8DC2A355E29516DD2FAF /* CustomRecorderControlTestable.swift */; };
 		BF0C8B154051EC0D440339D4 /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8A9D25A9680EB19444BC /* Localizable.strings */; };
 		BF0C8B2E933E4A0A91D7AF64 /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8195F23B30B8F4DD38D1 /* Localizable.strings */; };
 		BF0C8B2EE49F4753F663FEF2 /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8EF99FB3402D5A00B5C6 /* Localizable.strings */; };
@@ -172,6 +175,7 @@
 		BF0C8CBF5B4EE15FDB53C94B /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C861EE84489EF56879CBF /* InfoPlist.strings */; };
 		BF0C8CC5057406014FD612CC /* ATShortcut.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8BA452332236D972C60E /* ATShortcut.swift */; };
 		BF0C8CE3AE04A98400B9962F /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8D1BBBC02D57E16B454B /* InfoPlist.strings */; };
+		BF0C8CEBBC2E851D16FF4757 /* CustomRecorderControlTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = BF0C8308B436837FA3EDED86 /* CustomRecorderControlTests.swift */; };
 		BF0C8D1C57D74106018D073C /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C87F5D4AD51D6950C98B0 /* InfoPlist.strings */; };
 		BF0C8D610C93D48F572937F8 /* Localizable.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C8FBA6B0F4DEB510C71CB /* Localizable.strings */; };
 		BF0C8DD7EBC3BA1E86BF4BDB /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = BF0C841E403C1C6E8C65727E /* InfoPlist.strings */; };
@@ -390,6 +394,7 @@
 		BF0C82D44C2DFAA5D8F60394 /* sq */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = sq; path = Localizable.strings; sourceTree = "<group>"; };
 		BF0C82E4DE5A28800F1DA6E6 /* MissionControl.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MissionControl.swift; sourceTree = "<group>"; };
 		BF0C82E6C6038F057A5D8D1E /* convert_svg_to_png.sh */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.script.sh; path = convert_svg_to_png.sh; sourceTree = "<group>"; };
+		BF0C8308B436837FA3EDED86 /* CustomRecorderControlTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CustomRecorderControlTests.swift; sourceTree = "<group>"; };
 		BF0C831AA76CF82EAC7B60B3 /* gl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = gl; path = Localizable.strings; sourceTree = "<group>"; };
 		BF0C83258B2873D9CDC74EA5 /* preferences-controls.jpg */ = {isa = PBXFileReference; lastKnownFileType = image.jpeg; path = "preferences-controls.jpg"; sourceTree = "<group>"; };
 		BF0C832DEED422648209CCD2 /* unit-tests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = "unit-tests.xctest"; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -448,6 +453,7 @@
 		BF0C88C4940CA76FA801B881 /* preferences-appearance-details.jpg */ = {isa = PBXFileReference; lastKnownFileType = image.jpeg; path = "preferences-appearance-details.jpg"; sourceTree = "<group>"; };
 		BF0C890AF36F3EFD5CC4D114 /* bg */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = bg; path = Localizable.strings; sourceTree = "<group>"; };
 		BF0C89143F55C42D8A398C5A /* ku */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = ku; path = Localizable.strings; sourceTree = "<group>"; };
+		BF0C89231FD53C4D55E3CF9A /* Helpers.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Helpers.swift; sourceTree = "<group>"; };
 		BF0C892E4B0E4000C11DD102 /* ml */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = ml; path = InfoPlist.strings; sourceTree = "<group>"; };
 		BF0C893EAE329CE01783B70D /* gl */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = gl; path = InfoPlist.strings; sourceTree = "<group>"; };
 		BF0C8942D747B2B8E3A2BB53 /* da */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = da; path = Localizable.strings; sourceTree = "<group>"; };
@@ -499,6 +505,7 @@
 		BF0C8D7DE89E594FEE6DA692 /* ta */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = ta; path = Localizable.strings; sourceTree = "<group>"; };
 		BF0C8D87C20B7308B16498B6 /* et */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = et; path = InfoPlist.strings; sourceTree = "<group>"; };
 		BF0C8D9E024876AD9A92BE8D /* sr */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = sr; path = Localizable.strings; sourceTree = "<group>"; };
+		BF0C8DC2A355E29516DD2FAF /* CustomRecorderControlTestable.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CustomRecorderControlTestable.swift; sourceTree = "<group>"; };
 		BF0C8DCAC388B07C369E9771 /* test-base.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; path = "test-base.xcconfig"; sourceTree = "<group>"; };
 		BF0C8DF008F1EB5F23291A13 /* SpacesEvents.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SpacesEvents.swift; sourceTree = "<group>"; };
 		BF0C8DF173A246A0E0C30649 /* override_tags_on_poeditor.ts */ = {isa = PBXFileReference; lastKnownFileType = file.ts; path = override_tags_on_poeditor.ts; sourceTree = "<group>"; };
@@ -1039,6 +1046,8 @@
 				BF0C855CD9DBCAEFE48F9EA5 /* AXUIElementTests.swift */,
 				BF0C854910CCD4FB493C3A5D /* ImageScalingTests.swift */,
 				BF0C8AE65DDFD6359BE12CB3 /* resources */,
+				BF0C8308B436837FA3EDED86 /* CustomRecorderControlTests.swift */,
+				BF0C89231FD53C4D55E3CF9A /* Helpers.swift */,
 			);
 			path = "unit-tests";
 			sourceTree = "<group>";
@@ -1430,6 +1439,7 @@
 				1C9617C5839903D752070CF2 /* ImageTextButtonView.swift */,
 				BF0C896FD4907CD85D62C124 /* WindowlessAppIndicator.swift */,
 				BF0C8E63BE7394A6591E74E0 /* LightImageView.swift */,
+				BF0C8DC2A355E29516DD2FAF /* CustomRecorderControlTestable.swift */,
 			);
 			path = "generic-components";
 			sourceTree = "<group>";
@@ -2345,6 +2355,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				5F882F382EC3C63400110A9F /* CustomRecorderControlTestable.swift in Sources */,
 				BF0C81FA62D810342F59291A /* AppearanceTests.swift in Sources */,
 				5F4753072CEE5A2E002C6C5E /* AppearanceTestable.swift in Sources */,
 				BF0C8B787C76D9B961CC2F45 /* KeyboardEventsTests.swift in Sources */,
@@ -2355,6 +2366,8 @@
 				BF0C88FFEE7645A1966C7C4E /* AXUIElementTests.swift in Sources */,
 				BF0C866DE5D740AF7756CDCF /* ImageScalingTests.swift in Sources */,
 				BF0C8F9B8014AD21E68B1349 /* HelperExtensionsTestable.swift in Sources */,
+				BF0C8CEBBC2E851D16FF4757 /* CustomRecorderControlTests.swift in Sources */,
+				BF0C87B5EDCFC573CE220137 /* Helpers.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -2452,6 +2465,7 @@
 				BF0C88A9AB286CB7CDC1019E /* MainMenu.swift in Sources */,
 				BF0C826C7F8C5F68732FD75B /* DebugMenu.swift in Sources */,
 				BF0C8E5F4E4D5F7DAEE07C20 /* ThumbnailsPanelBackgroundView.swift in Sources */,
+				BF0C8AD478399D2E97AE3FB4 /* CustomRecorderControlTestable.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -3418,6 +3432,7 @@
 				COPY_PHASE_STRIP = NO;
 				CURRENT_PROJECT_VERSION = 1;
 				DEBUG_INFORMATION_FORMAT = dwarf;
+				DEVELOPMENT_TEAM = "${TEAM_ID}";
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				ENABLE_TESTABILITY = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu11;

alt-tab-macos.xcodeproj/xcshareddata/xcschemes/Test.xcscheme

@@ -23,7 +23,7 @@
       </BuildActionEntries>
    </BuildAction>
    <TestAction
-      buildConfiguration = "Release"
+      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       shouldUseLaunchSchemeArgsEnv = "NO">

config/test-debug.xcconfig

@@ -2,3 +2,7 @@
 
 #include "Pods/Target Support Files/Pods-unit-tests/Pods-unit-tests.debug.xcconfig"
 #include "test-base.xcconfig"
+
+SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG // for macro `#if DEBUG`
+OTHER_SWIFT_FLAGS = -driver-time-compilation -Xfrontend -warn-long-function-bodies=250 -Xfrontend -warn-long-expression-type-checking=250 // find slow compilation areas
+SWIFT_COMPILATION_MODE = incremental

scripts/run_tests.sh

@@ -5,4 +5,4 @@ set -ex
 xcodebuild -version
 xcodebuild -workspace alt-tab-macos.xcworkspace -scheme Release -showBuildSettings | grep SWIFT_VERSION
 
-set -o pipefail && xcodebuild test -workspace alt-tab-macos.xcworkspace -scheme Test | scripts/xcbeautify
+set -o pipefail && xcodebuild test -workspace alt-tab-macos.xcworkspace -scheme Test -configuration Release | scripts/xcbeautify

src/ui/generic-components/CustomRecorderControl.swift

@@ -1,4 +1,5 @@
 import Cocoa
+import Carbon.HIToolbox.Events
 import ShortcutRecorder
 
 class CustomRecorderControl: RecorderControl {
@@ -36,25 +37,25 @@ class CustomRecorderControl: RecorderControl {
         set(allowedModifierFlags: CustomRecorderControl.allowedModifiers.subtracting(restrictedModifiers), requiredModifierFlags: [], allowsEmptyModifierFlags: true)
     }
 
-    func alertIfSameShortcutAlreadyAssigned(_ shortcut: Shortcut, _ shortcutAlreadyAssigned: ATShortcut) {
-        let isArrowKeys = ["←", "→", "↑", "↓"].contains(shortcutAlreadyAssigned.id)
-        let isVimKeys = shortcutAlreadyAssigned.id.starts(with: "vimCycle")
-        let existingShortcutLabel = ControlsTab.shortcutControls[shortcutAlreadyAssigned.id]
+    func alertIfSameShortcutAlreadyAssigned(_ candidateId: String, _ candidateShortcut: Shortcut, _ shortcutAlreadyAssigned: String) {
+        let isArrowKeys = ["←", "→", "↑", "↓"].contains(shortcutAlreadyAssigned)
+        let isVimKeys = shortcutAlreadyAssigned.starts(with: "vimCycle")
+        let existingShortcut = ControlsTab.shortcutControls[shortcutAlreadyAssigned]!
         let alert = NSAlert()
         alert.alertStyle = .warning
         alert.messageText = NSLocalizedString("Conflicting shortcut", comment: "")
         alert.informativeText = String(format: NSLocalizedString("Shortcut already assigned to another action: %@", comment: ""),
-            (isArrowKeys ? "Arrow keys" : (isVimKeys ? "Vim keys" : existingShortcutLabel!.1)).replacingOccurrences(of: " ", with: "\u{00A0}"))
-        if !id.starts(with: "holdShortcut") {
+                                       (isArrowKeys ? "Arrow keys" : (isVimKeys ? "Vim keys" : existingShortcut.1)).replacingOccurrences(of: " ", with: "\u{00A0}"))
+        if !candidateId.starts(with: "holdShortcut") {
             alert.addButton(withTitle: NSLocalizedString("Unassign existing shortcut and continue", comment: "")).setAccessibilityFocused(true)
         }
         let cancelButton = alert.addButton(withTitle: NSLocalizedString("Cancel", comment: ""))
         cancelButton.keyEquivalent = "\u{1b}"
-        if id.starts(with: "holdShortcut") {
+        if candidateId.starts(with: "holdShortcut") {
             cancelButton.setAccessibilityFocused(true)
         }
         let userChoice = alert.runModal()
-        if !id.starts(with: "holdShortcut") && userChoice == .alertFirstButtonReturn {
+        if !candidateId.starts(with: "holdShortcut") && userChoice == .alertFirstButtonReturn {
             if isArrowKeys {
                 ControlsTab.arrowKeysCheckbox.state = .off
                 ControlsTab.arrowKeysEnabledCallback(ControlsTab.arrowKeysCheckbox)
@@ -64,61 +65,49 @@ class CustomRecorderControl: RecorderControl {
                 ControlsTab.vimKeysEnabledCallback(ControlsTab.vimKeysCheckbox)
                 LabelAndControl.controlWasChanged(ControlsTab.vimKeysCheckbox, nil)
             } else {
-                existingShortcutLabel!.0.objectValue = nil
-                ControlsTab.shortcutChangedCallback(existingShortcutLabel!.0)
-                LabelAndControl.controlWasChanged(existingShortcutLabel!.0, shortcutAlreadyAssigned.id)
+                existingShortcut.0.objectValue = nil
+                ControlsTab.shortcutChangedCallback(existingShortcut.0)
+                LabelAndControl.controlWasChanged(existingShortcut.0, shortcutAlreadyAssigned)
             }
-            ControlsTab.shortcutControls[id]!.0.objectValue = shortcut
+            ControlsTab.shortcutControls[candidateId]!.0.objectValue = candidateShortcut
             ControlsTab.shortcutChangedCallback(self)
-            LabelAndControl.controlWasChanged(self, id)
+            LabelAndControl.controlWasChanged(self, candidateId)
         }
     }
 
-    private func isShortcutAlreadyAssigned(_ shortcut: Shortcut) -> ATShortcut? {
-        let comboShortcutName = id.starts(with: "holdShortcut") ?
-            Preferences.indexToName("nextWindowShortcut", Preferences.nameToIndex(id)) :
-            (id.starts(with: "nextWindowShortcut") ?
-                Preferences.indexToName("holdShortcut", Preferences.nameToIndex(id)) : id)
-        let comboShortcut = comboShortcutName.flatMap { ControlsTab.shortcuts[$0]?.shortcut }
-        return (ControlsTab.shortcuts.first { (id2, s2) in
-            let shortcut2 = s2.shortcut
-            if id == id2
-                   || (shortcut2.keyCode == .none && shortcut2.carbonModifierFlags == 0)
-                   || id2.starts(with: "holdShortcut")
-                   || ((id.starts(with: "holdShortcut") || id.starts(with: "nextWindowShortcut")) && id2 == comboShortcutName) {
-                return false
-            }
-            if shortcut2.keyCode != (id.starts(with: "holdShortcut") ? comboShortcut?.keyCode : shortcut.keyCode) {
-                return false
-            }
-            if id.starts(with: "holdShortcut") {
-                if ((comboShortcut?.carbonModifierFlags ?? 0) ^ (ControlsTab.shortcuts[id]?.shortcut.carbonModifierFlags ?? 0) | shortcut.carbonModifierFlags)
-                       != (shortcut.carbonModifierFlags | shortcut2.carbonModifierFlags) {
-                    return false
-                }
-            } else if id.starts(with: "nextWindowShortcut") {
-                if ((comboShortcut?.carbonModifierFlags ?? 0) | shortcut.carbonModifierFlags)
-                       != ((comboShortcut?.carbonModifierFlags ?? 0) | shortcut2.carbonModifierFlags) {
-                    return false
-                }
-            } else if !ControlsTab.combinedModifiersMatch(shortcut2.carbonModifierFlags, shortcut.carbonModifierFlags) {
-                return false
-            }
-            return true
-        })?
-            .value
+    func alertIfShortcutReservedByMacos(_ candidateId: String, _ candidateShortcut: Shortcut, _ shortcutUsingEscape: String) {
+        let alert = NSAlert()
+        alert.alertStyle = .warning
+        alert.messageText = NSLocalizedString("Conflicting shortcut", comment: "")
+        alert.informativeText = NSLocalizedString("The ⎋ (escape) key is reserved by some macOS shortcuts (e.g. ⌘⌥⎋ will show the Force Quit Applications window).\n\nIf you want to use ⎋, make sure that Hold modifiers are neither: ⌘⌥, ⌘⌥⇧, or ⌘⌥⇧⌃", comment: "")
+        alert.addButton(withTitle: NSLocalizedString("Unassign existing shortcut and continue", comment: ""))
+        let cancelButton = alert.addButton(withTitle: NSLocalizedString("Cancel", comment: ""))
+        cancelButton.keyEquivalent = "\u{1b}"
+        cancelButton.setAccessibilityFocused(true)
+        let userChoice = alert.runModal()
+        if userChoice == .alertFirstButtonReturn {
+            guard candidateId != shortcutUsingEscape else { return }
+            let existingShortcut = ControlsTab.shortcutControls[shortcutUsingEscape]!
+            existingShortcut.0.objectValue = nil
+            ControlsTab.shortcutChangedCallback(existingShortcut.0)
+            LabelAndControl.controlWasChanged(existingShortcut.0, shortcutUsingEscape)
+            ControlsTab.shortcutControls[candidateId]!.0.objectValue = candidateShortcut
+            ControlsTab.shortcutChangedCallback(self)
+            LabelAndControl.controlWasChanged(self, candidateId)
+        }
     }
 }
 
 extension CustomRecorderControl: RecorderControlDelegate {
-    /// only allow modifiers: ⌥ -> valid, e -> invalid, ⌥e -> invalid
     func recorderControl(_ control: RecorderControl, canRecord shortcut: Shortcut) -> Bool {
-        if !clearable && shortcut.keyCode != .none {
-            return false
-        }
-        if let shortcutAlreadyAssigned = isShortcutAlreadyAssigned(shortcut) {
-            alertIfSameShortcutAlreadyAssigned(shortcut, shortcutAlreadyAssigned)
+        switch CustomRecorderControlTestable.isShortcutAcceptable(id, shortcut) {
+        case .accepted: return true
+        case .modifiersOnlyButContainsKeycode: return false
+        case .conflictWithExistingShortcut(let s): alertIfSameShortcutAlreadyAssigned(id, shortcut, s)
+        case .reservedByMacos(let s): alertIfShortcutReservedByMacos(id, shortcut, s)
         }
         return true
     }
-}
+}
+
+

src/ui/generic-components/CustomRecorderControlTestable.swift

@@ -0,0 +1,171 @@
+import Cocoa
+import Carbon.HIToolbox.Events
+import ShortcutRecorder
+
+class CustomRecorderControlTestable {
+    static func isShortcutAcceptable(_ candidateId: String, _ candidateShortcut: Shortcut) -> ShortcutAcceptance {
+        if candidateId.starts(with: "holdShortcut") && candidateShortcut.keyCode != .none {
+            return .modifiersOnlyButContainsKeycode
+        }
+        let newCombos = newCombinationsFromCandidate(candidateId, candidateShortcut)
+        let oldCombos = oldCombinationsExcludingTargetOfCandidate(candidateId)
+        // TODO: a user can assign a shortcut that's both .conflictWithExistingShortcut and .reservedByMacos
+        // It's a mess to deal with. Current implem may let them bypass isReservedByMacos. Would be nice to think about what UX to do here
+        if let alreadyAssigned = isAlreadyUsedByAnotherShortcut(newCombos, oldCombos) {
+            return .conflictWithExistingShortcut(shortcutAlreadyAssigned: alreadyAssigned)
+        }
+        if let shortcutUsingEscape = isReservedByMacos(newCombos) {
+            return .reservedByMacos(shortcutUsingEscape: shortcutUsingEscape)
+        }
+        return .accepted
+    }
+
+    static func newCombinationsFromCandidate(_ candidateId: String, _ candidateShortcut: Shortcut) -> [(String, Shortcut)] {
+        var combos = [(String, Shortcut)]()
+        for atShortcut in ControlsTab.shortcuts.values {
+            guard atShortcut.id != candidateId
+                      && !((candidateId.starts(with: "holdShortcut") || candidateId.starts(with: "nextWindowShortcut")) && (atShortcut.id.starts(with: "holdShortcut") || atShortcut.id.starts(with: "nextWindowShortcut")) && Preferences.nameToIndex(candidateId) != Preferences.nameToIndex(atShortcut.id))
+                      && !(atShortcut.shortcut.keyCode == .none && atShortcut.shortcut.modifierFlags == []) else { continue }
+            // candidate is holdShortcut
+            if candidateId.starts(with: "holdShortcut") {
+                // combine with local shortcut
+                if (!atShortcut.id.starts(with: "holdShortcut") && !atShortcut.id.starts(with: "nextWindowShortcut"))
+                    // combine with nextWindowShortcut of same index
+                    || (atShortcut.id.starts(with: "nextWindowShortcut") && Preferences.nameToIndex(candidateId) == Preferences.nameToIndex(atShortcut.id)) {
+                    combos.append((atShortcut.id, Shortcut(code: atShortcut.shortcut.keyCode, modifierFlags: [candidateShortcut.modifierFlags, atShortcut.shortcut.modifierFlags], characters: nil, charactersIgnoringModifiers: nil)))
+                }
+            // candidate is nextWindowShortcut
+            } else if candidateId.starts(with: "nextWindowShortcut") {
+                // combine with holdShortcut of same index
+                if (atShortcut.id.starts(with: "holdShortcut") && Preferences.nameToIndex(candidateId) == Preferences.nameToIndex(atShortcut.id)) {
+                    combos.append((candidateId, Shortcut(code: candidateShortcut.keyCode, modifierFlags: [candidateShortcut.modifierFlags, atShortcut.shortcut.modifierFlags], characters: nil, charactersIgnoringModifiers: nil)))
+                }
+            // candidate is a local shortcut
+            } else {
+                // combine with everything except a nextWindowShortcut
+                if !atShortcut.id.starts(with: "nextWindowShortcut") {
+                    combos.append((candidateId, Shortcut(code: candidateShortcut.keyCode, modifierFlags: [candidateShortcut.modifierFlags, atShortcut.shortcut.modifierFlags], characters: nil, charactersIgnoringModifiers: nil)))
+                }
+            }
+        }
+        return combos
+    }
+
+    static func oldCombinationsExcludingTargetOfCandidate(_ candidateId: String) -> [(String, Shortcut)] {
+        var holds = [ATShortcut]()
+        var nonHolds = [ATShortcut]()
+        for atShortcut in ControlsTab.shortcuts.values {
+            guard !((candidateId.starts(with: "holdShortcut") || candidateId.starts(with: "nextWindowShortcut")) && (atShortcut.id.starts(with: "holdShortcut") || atShortcut.id.starts(with: "nextWindowShortcut")) && Preferences.nameToIndex(candidateId) == Preferences.nameToIndex(atShortcut.id) )
+                      && !(atShortcut.shortcut.keyCode == .none && atShortcut.shortcut.modifierFlags == []) else { continue }
+            if atShortcut.id.starts(with: "holdShortcut") {
+                holds.append(atShortcut)
+            } else {
+                nonHolds.append(atShortcut)
+            }
+        }
+        var combos = [(String, Shortcut)]()
+        for hold in holds {
+            for nonHold in nonHolds {
+                guard !nonHold.id.starts(with: "nextWindowShortcut") || Preferences.nameToIndex(nonHold.id) == Preferences.nameToIndex(hold.id) else { continue }
+                combos.append((nonHold.id, Shortcut(code: nonHold.shortcut.keyCode, modifierFlags: [hold.shortcut.modifierFlags, nonHold.shortcut.modifierFlags], characters: nil, charactersIgnoringModifiers: nil)))
+            }
+        }
+        return combos
+    }
+
+    static func isReservedByMacos(_ newCombinationsFromCandidate: [(String, Shortcut)] ) -> String? {
+        for r in (ReservedMacosShortcut.allCases.map { $0.basicShortcut }) {
+            for c in newCombinationsFromCandidate {
+                if c.1.carbonKeyCode == r.carbonKeyCode && c.1.carbonModifierFlags == r.carbonModifierFlags {
+                    return c.0
+                }
+            }
+        }
+        return nil
+    }
+
+    static func isAlreadyUsedByAnotherShortcut(_ newCombos: [(String, Shortcut)] , _ oldCombos: [(String, Shortcut)]) -> String? {
+        for newCombo in newCombos {
+            for oldCombo in oldCombos {
+                guard !(newCombo.0 == oldCombo.0) else { continue }
+                if (newCombo.1.keyCode == oldCombo.1.keyCode && newCombo.1.modifierFlags == oldCombo.1.modifierFlags)
+                    // special case when 2 nextWindowShortcuts are modifiers-only (e.g. S1: alt + shift, S2: alt+command + shift)
+                    // they will conflict if they their holdShortcuts are included in the other's holdShortcuts
+                    || (newCombo.1.keyCode == .none && oldCombo.1.keyCode == .none && (newCombo.1.modifierFlags.isSuperset(of: oldCombo.1.modifierFlags) || oldCombo.1.modifierFlags.isSuperset(of: newCombo.1.modifierFlags))) {
+                    return oldCombo.0
+                }
+            }
+        }
+        return nil
+    }
+
+    /// commandTab and commandKeyAboveTab are self-contained in the "nextWindowShortcut" shortcuts
+    /// but the keys of commandShiftTab can be spread between holdShortcut and a local shortcut
+    static func combinedModifiersMatch(_ modifiers1: UInt32, _ modifiers2: UInt32) -> Bool {
+        return (0..<Preferences.holdShortcut.count).contains {
+            if let holdShortcut = ControlsTab.shortcuts[Preferences.indexToName("holdShortcut", $0)] {
+                return (holdShortcut.shortcut.carbonModifierFlags | modifiers1) == (holdShortcut.shortcut.carbonModifierFlags | modifiers2)
+            }
+            return false
+        }
+    }
+}
+
+enum ShortcutAcceptance: Equatable {
+    case accepted
+    case modifiersOnlyButContainsKeycode
+    case conflictWithExistingShortcut(shortcutAlreadyAssigned: String)
+    case reservedByMacos(shortcutUsingEscape: String)
+
+    static func == (lhs: ShortcutAcceptance, rhs: ShortcutAcceptance) -> Bool {
+        switch (lhs, rhs) {
+        case (.accepted, .accepted),
+             (.modifiersOnlyButContainsKeycode, .modifiersOnlyButContainsKeycode),
+             (.reservedByMacos, .reservedByMacos),
+             (.conflictWithExistingShortcut, .conflictWithExistingShortcut):
+            return true
+        default:
+            return false
+        }
+    }
+}
+
+enum ReservedMacosShortcut: CaseIterable {
+    case forceQuitApplicationsDialog
+    case forceQuitActiveApp
+    case reservedForUnknownReason
+
+    var basicShortcut: Shortcut {
+        switch self {
+        case .forceQuitApplicationsDialog: return Shortcut(code: KeyCode.escape, modifierFlags: [.command, .option], characters: nil, charactersIgnoringModifiers: nil)
+        case .forceQuitActiveApp: return Shortcut(code: KeyCode.escape, modifierFlags: [.command, .option, .shift], characters: nil, charactersIgnoringModifiers: nil)
+        case .reservedForUnknownReason: return Shortcut(code: KeyCode.escape, modifierFlags: [.command, .option, .shift, .control], characters: nil, charactersIgnoringModifiers: nil)
+        }
+    }
+}
+
+extension Shortcut {
+    /// ShortcutRecorder doesn't provide a Shortcut.toString() that outputs the same format as Shortcut.init(keyEquivalent:)
+    /// This helper provides this, on a limited range of shortcuts, since it used only for testing
+    var keyEquivalent: String {
+        get {
+            let readableStringRepresentation = self.readableStringRepresentation(isASCII: true).lowercased()
+            // for keycode-only shortcuts, readableStringRepresentation works
+            if keyCode != .none && modifierFlags == [] && !readableStringRepresentation.isEmpty {
+                return readableStringRepresentation
+            }
+            // for other shortcuts, we need to replace modifiers with unicode symbols (e.g. "Option-" -> "⌥")
+            let flags: [(NSEvent.ModifierFlags, String)] = [
+                (.command, "⌘"),
+                (.option, "⌥"),
+                (.control, "⌃"),
+                (.shift, "⇧")
+            ]
+            let mods = flags.reduce("") {
+                $0 + (self.modifierFlags.contains($1.0) ? $1.1 : "")
+            }
+            let chars = readableStringRepresentation.replacingOccurrences(of: "\\b(command|option|shift|control)-", with: "", options: .regularExpression)
+            return mods + chars
+        }
+    }
+}

src/ui/preferences-window/tabs/controls/ControlsTab.swift

@@ -1,4 +1,5 @@
 import Cocoa
+import Carbon.HIToolbox.Events
 import ShortcutRecorder
 
 class ControlsTab {
@@ -157,21 +158,10 @@ class ControlsTab {
         }
     }
 
-    /// commandTab and commandKeyAboveTab are self-contained in the "nextWindowShortcut" shortcuts
-    /// but the keys of commandShiftTab can be spread between holdShortcut and a local shortcut
-    static func combinedModifiersMatch(_ modifiers1: UInt32, _ modifiers2: UInt32) -> Bool {
-        return (0..<Preferences.holdShortcut.count).contains {
-            if let holdShortcut = shortcuts[Preferences.indexToName("holdShortcut", $0)] {
-                return (holdShortcut.shortcut.carbonModifierFlags | modifiers1) == (holdShortcut.shortcut.carbonModifierFlags | modifiers2)
-            }
-            return false
-        }
-    }
-
     static func toggleNativeCommandTabIfNeeded() {
         let nativeHotkeys: [CGSSymbolicHotKey: (Shortcut) -> Bool] = [
             .commandTab: { (shortcut) in shortcut.carbonModifierFlags == cmdKey && shortcut.carbonKeyCode == kVK_Tab },
-            .commandShiftTab: { (shortcut) in combinedModifiersMatch(shortcut.carbonModifierFlags, UInt32(cmdKey | shiftKey)) && shortcut.carbonKeyCode == kVK_Tab },
+            .commandShiftTab: { (shortcut) in CustomRecorderControlTestable.combinedModifiersMatch(shortcut.carbonModifierFlags, UInt32(cmdKey | shiftKey)) && shortcut.carbonKeyCode == kVK_Tab },
             .commandKeyAboveTab: { (shortcut) in shortcut.carbonModifierFlags == cmdKey && shortcut.carbonKeyCode == kVK_ANSI_Grave },
         ]
         var overlappingHotkeys = shortcuts.values.compactMap { (atShortcut) in nativeHotkeys.first { $1(atShortcut.shortcut) }?.key }

src/ui/preferences-window/tabs/controls/ShortcutsWhenActiveSheet.swift

@@ -3,21 +3,21 @@ import Cocoa
 class ShortcutsWhenActiveSheet: SheetWindow {
     override func makeContentView() -> NSView {
         let focusWindowShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Focus selected window", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "focusWindowShortcut", Preferences.focusWindowShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Focus selected window", comment: ""), "focusWindowShortcut", Preferences.focusWindowShortcut, labelPosition: .right)[0]])
         let previousWindowShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Select previous window", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "previousWindowShortcut", Preferences.previousWindowShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Select previous window", comment: ""), "previousWindowShortcut", Preferences.previousWindowShortcut, labelPosition: .right)[0]])
         let cancelShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Cancel and hide", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "cancelShortcut", Preferences.cancelShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Cancel and hide", comment: ""), "cancelShortcut", Preferences.cancelShortcut, labelPosition: .right)[0]])
         let closeWindowShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Close window", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "closeWindowShortcut", Preferences.closeWindowShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Close window", comment: ""), "closeWindowShortcut", Preferences.closeWindowShortcut, labelPosition: .right)[0]])
         let minDeminWindowShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Minimize/Deminimize window", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "minDeminWindowShortcut", Preferences.minDeminWindowShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Minimize/Deminimize window", comment: ""), "minDeminWindowShortcut", Preferences.minDeminWindowShortcut, labelPosition: .right)[0]])
         let toggleFullscreenWindowShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Fullscreen/Defullscreen window", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "toggleFullscreenWindowShortcut", Preferences.toggleFullscreenWindowShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Fullscreen/Defullscreen window", comment: ""), "toggleFullscreenWindowShortcut", Preferences.toggleFullscreenWindowShortcut, labelPosition: .right)[0]])
         let quitAppShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Quit app", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "quitAppShortcut", Preferences.quitAppShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Quit app", comment: ""), "quitAppShortcut", Preferences.quitAppShortcut, labelPosition: .right)[0]])
         let hideShowAppShortcut = TableGroupView.Row(leftTitle: NSLocalizedString("Hide/Show app", comment: ""),
-            rightViews: [LabelAndControl.makeLabelWithRecorder("", "hideShowAppShortcut", Preferences.hideShowAppShortcut, labelPosition: .right)[0]])
+            rightViews: [LabelAndControl.makeLabelWithRecorder(NSLocalizedString("Hide/Show app", comment: ""), "hideShowAppShortcut", Preferences.hideShowAppShortcut, labelPosition: .right)[0]])
         let table = TableGroupView(title: NSLocalizedString("Shortcuts When Active", comment: ""), width: SheetWindow.width)
         _ = table.addRow(focusWindowShortcut)
         _ = table.addRow(previousWindowShortcut)

unit-tests/CustomRecorderControlTests.swift

@@ -0,0 +1,63 @@
+import XCTest
+import ShortcutRecorder
+
+final class CustomRecorderControlTests: XCTestCase {
+    func testIsShortcutAcceptable() {
+        // .accepted
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘")!), .accepted)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("previousWindowShortcut", Shortcut(keyEquivalent: "⇧⇥")!), .accepted)
+        ControlsTab.shortcuts["holdShortcut"] = ATShortcut(Shortcut(keyEquivalent: "⌘⌥")!, "holdShortcut", .global, .up)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌥")!), .accepted)
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+
+        // .modifiersOnlyButContainsKeycode
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘⇧")!), .accepted)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘e")!), .modifiersOnlyButContainsKeycode)
+
+        // .reservedByMacos
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘")!), .accepted) // ⌘⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("previousWindowShortcut", Shortcut(keyEquivalent: "⌘⇧")!), .accepted) // ⌘⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("previousWindowShortcut", Shortcut(keyEquivalent: "⌘⌃⇧")!), .accepted) // ⌘⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘⌥")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘⌥⇧")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⇧⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌘⌥⌃⇧")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⌃⇧⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("cancelShortcut", Shortcut(keyEquivalent: "⌘⇧⎋")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⇧⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("cancelShortcut", Shortcut(keyEquivalent: "⌘⇧⌃⎋")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⇧⌃⎋
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("cancelShortcut", Shortcut(keyEquivalent: "⌘⎋")!), .reservedByMacos(shortcutUsingEscape: "cancelShortcut")) // ⌘⌥⎋
+
+        // .conflictWithExistingShortcut
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("vimCycleRight", Shortcut(keyEquivalent: "l")!), .accepted)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut2", Shortcut(keyEquivalent: "⇧⇥")!), .accepted)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("vimCycleLeft", Shortcut(keyEquivalent: "h")!), .conflictWithExistingShortcut(shortcutAlreadyAssigned: "hideShowAppShortcut"))
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut2", Shortcut(keyEquivalent: "⇥")!), .conflictWithExistingShortcut(shortcutAlreadyAssigned: "nextWindowShortcut"))
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut", Shortcut(keyEquivalent: "⇧")!), .conflictWithExistingShortcut(shortcutAlreadyAssigned: "previousWindowShortcut"))
+
+        // alt + shift+tab / alt+shift + tab => pressing tab is ambiguous which one should trigger
+        ControlsTab.shortcuts["previousWindowShortcut"] = ATShortcut(Shortcut(keyEquivalent: "p")!, "previousWindowShortcut", .local, .down)
+        ControlsTab.shortcuts["nextWindowShortcut2"] = ATShortcut(Shortcut(keyEquivalent: "⇧⇥")!, "nextWindowShortcut2", .global, .down)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("holdShortcut", Shortcut(keyEquivalent: "⌥⇧")!), .conflictWithExistingShortcut(shortcutAlreadyAssigned: "nextWindowShortcut2"))
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+
+        // alt + shift / alt+command + shift => doesn't work if allowed
+        ControlsTab.shortcuts["nextWindowShortcut"] = ATShortcut(Shortcut(keyEquivalent: "⇧")!, "nextWindowShortcut", .global, .down)
+        ControlsTab.shortcuts["holdShortcut2"] = ATShortcut(Shortcut(keyEquivalent: "⌘⌥")!, "holdShortcut2", .global, .up)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut2", Shortcut(keyEquivalent: "⇧")!), .conflictWithExistingShortcut(shortcutAlreadyAssigned: "nextWindowShortcut"))
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+
+        // Shortcut 1: alt + tab / Shortcut 2: alt + command+tab => works if allowed
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut2", Shortcut(keyEquivalent: "⌘⇥")!), .accepted)
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+
+        // Shortcut 1: alt + tab / Shortcut 2: alt+command + tab [assign Shortcut 2 last] => works if allowed
+        ControlsTab.shortcuts["holdShortcut2"] = ATShortcut(Shortcut(keyEquivalent: "⌘⌥")!, "holdShortcut2", .global, .up)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut2", Shortcut(keyEquivalent: "⇥")!), .accepted)
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+
+        // Shortcut 1: alt + tab / Shortcut 2: alt+command + tab [assign Shortcut 1 last] => works if allowed
+        ControlsTab.shortcuts["holdShortcut2"] = ATShortcut(Shortcut(keyEquivalent: "⌘⌥")!, "holdShortcut2", .global, .up)
+        ControlsTab.shortcuts["nextWindowShortcut"] = ATShortcut(Shortcut(keyEquivalent: "t")!, "nextWindowShortcut", .global, .down)
+        ControlsTab.shortcuts["nextWindowShortcut2"] = ATShortcut(Shortcut(keyEquivalent: "⇥")!, "nextWindowShortcut2", .global, .down)
+        XCTAssertEqual(CustomRecorderControlTestable.isShortcutAcceptable("nextWindowShortcut", Shortcut(keyEquivalent: "⇥")!), .accepted)
+        ControlsTab.shortcuts = ControlsTab.defaultShortcuts
+    }
+}

unit-tests/Helpers.swift

@@ -0,0 +1,11 @@
+import XCTest
+
+func XCTAssertArraysEqualUnordered<T: Comparable>(
+    _ array1: [T],
+    _ array2: [T],
+    _ message: @autoclosure () -> String = "",
+    file: StaticString = #file,
+    line: UInt = #line
+) {
+    XCTAssertEqual(array1.sorted(), array2.sorted(), message(), file: file, line: line)
+}

unit-tests/Mocks.swift

@@ -10,7 +10,7 @@ class App {
 }
 
 class ControlsTab {
-    static let shortcuts = [
+    static let defaultShortcuts = [
         "holdShortcut": ATShortcut(Shortcut(keyEquivalent: "⌥")!, "holdShortcut", .global, .up, 0),
         "holdShortcut2": ATShortcut(Shortcut(keyEquivalent: "⌥")!, "holdShortcut2", .global, .up, 1),
         "holdShortcut3": ATShortcut(Shortcut(keyEquivalent: "⌥")!, "holdShortcut3", .global, .up, 2),
@@ -33,6 +33,7 @@ class ControlsTab {
         "quitAppShortcut": ATShortcut(Shortcut(keyEquivalent: "q")!, "quitAppShortcut", .local, .down),
         "hideShowAppShortcut": ATShortcut(Shortcut(keyEquivalent: "h")!, "hideShowAppShortcut", .local, .down),
     ]
+    static var shortcuts = defaultShortcuts
 
     static func executeAction(_ action: String) {
         shortcutsActionsTriggered.append(action)
@@ -62,6 +63,7 @@ class Logger {
 
 class Preferences {
     static var shortcutStyle: [ShortcutStylePreference] = [.focusOnRelease, .focusOnRelease, .focusOnRelease, .focusOnRelease]
+    static var holdShortcut = ["⌥", "⌥", "⌥"]
 
     static func indexToName(_ baseName: String, _ index: Int) -> String {
         return baseName + (index == 0 ? "" : String(index + 1))