Add Split Tab option to tab context menu

src/cascadia/TerminalApp/Resources/en-US/Resources.resw

@@ -226,15 +226,15 @@
     <value>Warnings were found while parsing your keybindings:</value>
   </data>
   <data name="TooManyKeysForChord" xml:space="preserve">
-    <value>&#x2022; Found a keybinding with too many strings for the "keys" array. There should only be one string value in the "keys" array.</value>
-    <comment>{Locked="\"keys\"","&#x2022;"} This glyph is a bullet, used in a bulleted list.</comment>
+    <value>&amp;#x2022; Found a keybinding with too many strings for the "keys" array. There should only be one string value in the "keys" array.</value>
+    <comment>{Locked="\"keys\"","&amp;#x2022;"} This glyph is a bullet, used in a bulleted list.</comment>
   </data>
   <data name="FailedToParseSubCommands" xml:space="preserve">
-    <value>&#x2022; Failed to parse all subcommands of nested command.</value>
+    <value>&amp;#x2022; Failed to parse all subcommands of nested command.</value>
   </data>
   <data name="MissingRequiredParameter" xml:space="preserve">
-    <value>&#x2022; Found a keybinding that was missing a required parameter value. This keybinding will be ignored.</value>
-    <comment>{Locked="&#x2022;"} This glyph is a bullet, used in a bulleted list.</comment>
+    <value>&amp;#x2022; Found a keybinding that was missing a required parameter value. This keybinding will be ignored.</value>
+    <comment>{Locked="&amp;#x2022;"} This glyph is a bullet, used in a bulleted list.</comment>
   </data>
   <data name="LegacyGlobalsProperty" xml:space="preserve">
     <value>The "globals" property is deprecated - your settings might need updating. </value>
@@ -662,6 +662,9 @@
   <data name="DropPathTabRun.Text" xml:space="preserve">
     <value>Open a new tab in given starting directory</value>
   </data>
+  <data name="SplitTabText" xml:space="preserve">
+    <value>Split Tab</value>
+  </data>
   <data name="DropPathTabNewWindow.Text" xml:space="preserve">
     <value>Open a new window with given starting directory</value>
   </data>

src/cascadia/TerminalApp/TabManagement.cpp

@@ -192,6 +192,16 @@ namespace winrt::TerminalApp::implementation
             }
         });
 
+        newTabImpl->SplitTabRequested([weakTab, weakThis{ get_weak() }]() {
+            auto page{ weakThis.get() };
+            auto tab{ weakTab.get() };
+
+            if (page && tab)
+            {
+                page->_SplitTab(*tab);
+            }
+        });
+
         auto tabViewItem = newTabImpl->TabViewItem();
         _tabView.TabItems().Append(tabViewItem);
 
@@ -357,6 +367,20 @@ namespace winrt::TerminalApp::implementation
         CATCH_LOG();
     }
 
+    // Method Description:
+    // - Sets the specified tab as the focused tab and splits its active pane
+    // Arguments:
+    // - tab: tab to split
+    void TerminalPage::_SplitTab(TerminalTab& tab)
+    {
+        try
+        {
+            _SetFocusedTab(tab);
+            _SplitPane(tab, SplitState::Automatic, SplitType::Duplicate);
+        }
+        CATCH_LOG();
+    }
+
     // Method Description:
     // - Removes the tab (both TerminalControl and XAML) after prompting for approval
     // Arguments:

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -1246,6 +1246,33 @@ namespace winrt::TerminalApp::implementation
             return;
         }
 
+        _SplitPane(*focusedTab, splitType, splitMode, splitSize, newTerminalArgs);
+    }
+
+    // Method Description:
+    // - Split the focused pane of the given tab, either horizontally or vertically, and place the
+    //   given TermControl into the newly created pane.
+    // - If splitType == SplitState::None, this method does nothing.
+    // Arguments:
+    // - tab: The tab that is going to be split.
+    // - splitType: one value from the TerminalApp::SplitState enum, indicating how the
+    //   new pane should be split from its parent.
+    // - splitMode: value from TerminalApp::SplitType enum, indicating the profile to be used in the newly split pane.
+    // - newTerminalArgs: An object that may contain a blob of parameters to
+    //   control which profile is created and with possible other
+    //   configurations. See CascadiaSettings::BuildSettings for more details.
+    void TerminalPage::_SplitPane(TerminalTab& tab,
+                                  const SplitState splitType,
+                                  const SplitType splitMode,
+                                  const float splitSize,
+                                  const NewTerminalArgs& newTerminalArgs)
+    {
+        // Do nothing if we're requesting no split.
+        if (splitType == SplitState::None)
+        {
+            return;
+        }
+
         try
         {
             TerminalSettingsCreateResult controlSettings{ nullptr };
@@ -1254,12 +1281,12 @@ namespace winrt::TerminalApp::implementation
 
             if (splitMode == SplitType::Duplicate)
             {
-                std::optional<GUID> current_guid = focusedTab->GetFocusedProfile();
+                std::optional<GUID> current_guid = tab.GetFocusedProfile();
                 if (current_guid)
                 {
                     profileFound = true;
                     controlSettings = TerminalSettings::CreateWithProfileByID(_settings, current_guid.value(), *_bindings);
-                    const auto workingDirectory = focusedTab->GetActiveTerminalControl().WorkingDirectory();
+                    const auto workingDirectory = tab.GetActiveTerminalControl().WorkingDirectory();
                     const auto validWorkingDirectory = !workingDirectory.empty();
                     if (validWorkingDirectory)
                     {
@@ -1295,10 +1322,10 @@ namespace winrt::TerminalApp::implementation
             auto realSplitType = splitType;
             if (realSplitType == SplitState::Automatic)
             {
-                realSplitType = focusedTab->PreCalculateAutoSplit(availableSpace);
+                realSplitType = tab.PreCalculateAutoSplit(availableSpace);
             }
 
-            const auto canSplit = focusedTab->PreCalculateCanSplit(realSplitType, splitSize, availableSpace);
+            const auto canSplit = tab.PreCalculateCanSplit(realSplitType, splitSize, availableSpace);
             if (!canSplit)
             {
                 return;
@@ -1307,11 +1334,11 @@ namespace winrt::TerminalApp::implementation
             auto newControl = _InitControl(controlSettings, controlConnection);
 
             // Hookup our event handlers to the new terminal
-            _RegisterTerminalEvents(newControl, *focusedTab);
+            _RegisterTerminalEvents(newControl, tab);
 
             _UnZoomIfNeeded();
 
-            focusedTab->SplitPane(realSplitType, splitSize, realGuid, newControl);
+            tab.SplitPane(realSplitType, splitSize, realGuid, newControl);
         }
         CATCH_LOG();
     }

src/cascadia/TerminalApp/TerminalPage.h

@@ -219,6 +219,8 @@ namespace winrt::TerminalApp::implementation
         void _DuplicateFocusedTab();
         void _DuplicateTab(const TerminalTab& tab);
 
+        void _SplitTab(TerminalTab& tab);
+
         winrt::Windows::Foundation::IAsyncAction _HandleCloseTabRequested(winrt::TerminalApp::TabBase tab);
         void _CloseTabAtIndex(uint32_t index);
         void _RemoveTab(const winrt::TerminalApp::TabBase& tab);
@@ -254,6 +256,11 @@ namespace winrt::TerminalApp::implementation
                         const Microsoft::Terminal::Settings::Model::SplitType splitMode = Microsoft::Terminal::Settings::Model::SplitType::Manual,
                         const float splitSize = 0.5f,
                         const Microsoft::Terminal::Settings::Model::NewTerminalArgs& newTerminalArgs = nullptr);
+        void _SplitPane(TerminalTab& tab,
+                        const Microsoft::Terminal::Settings::Model::SplitState splitType,
+                        const Microsoft::Terminal::Settings::Model::SplitType splitMode = Microsoft::Terminal::Settings::Model::SplitType::Manual,
+                        const float splitSize = 0.5f,
+                        const Microsoft::Terminal::Settings::Model::NewTerminalArgs& newTerminalArgs = nullptr);
         void _ResizePane(const Microsoft::Terminal::Settings::Model::ResizeDirection& direction);
         void _ToggleSplitOrientation();
 

src/cascadia/TerminalApp/TerminalTab.cpp

@@ -936,12 +936,30 @@ namespace winrt::TerminalApp::implementation
             duplicateTabMenuItem.Icon(duplicateTabSymbol);
         }
 
+        Controls::MenuFlyoutItem splitTabMenuItem;
+        {
+            // "Split Tab"
+            Controls::FontIcon splitTabSymbol;
+            splitTabSymbol.FontFamily(Media::FontFamily{ L"Segoe MDL2 Assets" });
+            splitTabSymbol.Glyph(L"\xF246"); // ViewDashboard
+
+            splitTabMenuItem.Click([weakThis](auto&&, auto&&) {
+                if (auto tab{ weakThis.get() })
+                {
+                    tab->_SplitTabRequestedHandlers();
+                }
+            });
+            splitTabMenuItem.Text(RS_(L"SplitTabText"));
+            splitTabMenuItem.Icon(splitTabSymbol);
+        }
+
         // Build the menu
         Controls::MenuFlyout contextMenuFlyout;
         Controls::MenuFlyoutSeparator menuSeparator;
         contextMenuFlyout.Items().Append(chooseColorMenuItem);
         contextMenuFlyout.Items().Append(renameTabMenuItem);
         contextMenuFlyout.Items().Append(duplicateTabMenuItem);
+        contextMenuFlyout.Items().Append(splitTabMenuItem);
         contextMenuFlyout.Items().Append(menuSeparator);
 
         // GH#5750 - When the context menu is dismissed with ESC, toss the focus
@@ -1315,4 +1333,5 @@ namespace winrt::TerminalApp::implementation
     DEFINE_EVENT(TerminalTab, ColorCleared, _colorCleared, winrt::delegate<>);
     DEFINE_EVENT(TerminalTab, TabRaiseVisualBell, _TabRaiseVisualBellHandlers, winrt::delegate<>);
     DEFINE_EVENT(TerminalTab, DuplicateRequested, _DuplicateRequestedHandlers, winrt::delegate<>);
+    DEFINE_EVENT(TerminalTab, SplitTabRequested, _SplitTabRequestedHandlers, winrt::delegate<>);
 }

src/cascadia/TerminalApp/TerminalTab.h

@@ -94,6 +94,7 @@ namespace winrt::TerminalApp::implementation
         DECLARE_EVENT(ColorCleared, _colorCleared, winrt::delegate<>);
         DECLARE_EVENT(TabRaiseVisualBell, _TabRaiseVisualBellHandlers, winrt::delegate<>);
         DECLARE_EVENT(DuplicateRequested, _DuplicateRequestedHandlers, winrt::delegate<>);
+        DECLARE_EVENT(SplitTabRequested, _SplitTabRequestedHandlers, winrt::delegate<>);
         TYPED_EVENT(TaskbarProgressChanged, IInspectable, IInspectable);
 
     private: