Introduce ExpandSelectionToWord action (#13765)

## Summary of the Pull Request
Introduces a new action `expandSelectionToWord()` which expands the beginning and end of the selection to encompass the word(s) it's on. This was implemented as a conditional keybinding where the key chord is passed through to the terminal if no selection is active (similar to `copy()`).
It is not bound to anything by default.

## PR Checklist
* [x] Closes #8274
* [x] Schema updated.

## Validation Steps Performed
- Scenario in #8274:
	- search for some text in the find dialog
	- ESC to close the dialog
	- execute `expandSelectionToWord()`
	- the new selection encompasses the whole word
- mark mode
	- move onto a word
	- execute `expandSelectionToWord()`
- mouse selection (same as above)
- select a portion of two words --> new selection fully encompasses both words

doc/cascadia/profiles.schema.json

@@ -315,6 +315,7 @@
         "commandPalette",
         "copy",
         "duplicateTab",
+        "expandSelectionToWord",
         "exportBuffer",
         "find",
         "findMatch",

src/cascadia/TerminalApp/AppActionHandlers.cpp

@@ -1156,4 +1156,14 @@ namespace winrt::TerminalApp::implementation
             args.Handled(handled);
         }
     }
+
+    void TerminalPage::_HandleExpandSelectionToWord(const IInspectable& /*sender*/,
+                                                    const ActionEventArgs& args)
+    {
+        if (const auto& control{ _GetActiveControl() })
+        {
+            const auto handled = control.ExpandSelectionToWord();
+            args.Handled(handled);
+        }
+    }
 }

src/cascadia/TerminalControl/ControlCore.cpp

@@ -1147,6 +1147,17 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return false;
     }
 
+    bool ControlCore::ExpandSelectionToWord()
+    {
+        if (_terminal->IsSelectionActive())
+        {
+            _terminal->ExpandSelectionToWord();
+            _updateSelectionUI();
+            return true;
+        }
+        return false;
+    }
+
     // Method Description:
     // - Pre-process text pasted (presumably from the clipboard)
     //   before sending it over the terminal's connection.

src/cascadia/TerminalControl/ControlCore.h

@@ -87,6 +87,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         void ToggleMarkMode();
         Control::SelectionInteractionMode SelectionMode() const;
         bool SwitchSelectionEndpoint();
+        bool ExpandSelectionToWord();
         bool TryMarkModeKeybinding(const WORD vkey,
                                    const ::Microsoft::Terminal::Core::ControlKeyStates modifiers);
 

src/cascadia/TerminalControl/ControlCore.idl

@@ -91,6 +91,7 @@ namespace Microsoft.Terminal.Control
         Boolean ToggleBlockSelection();
         void ToggleMarkMode();
         Boolean SwitchSelectionEndpoint();
+        Boolean ExpandSelectionToWord();
         void ClearBuffer(ClearBufferType clearType);
 
         void SetHoveredCell(Microsoft.Terminal.Core.Point terminalPosition);

src/cascadia/TerminalControl/TermControl.cpp

@@ -1981,6 +1981,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return _core.SwitchSelectionEndpoint();
     }
 
+    bool TermControl::ExpandSelectionToWord()
+    {
+        return _core.ExpandSelectionToWord();
+    }
+
     void TermControl::Close()
     {
         if (!_IsClosing())

src/cascadia/TerminalControl/TermControl.h

@@ -41,6 +41,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         bool ToggleBlockSelection();
         void ToggleMarkMode();
         bool SwitchSelectionEndpoint();
+        bool ExpandSelectionToWord();
         void Close();
         Windows::Foundation::Size CharacterDimensions() const;
         Windows::Foundation::Size MinimumSize();

src/cascadia/TerminalControl/TermControl.idl

@@ -55,6 +55,7 @@ namespace Microsoft.Terminal.Control
         Boolean ToggleBlockSelection();
         void ToggleMarkMode();
         Boolean SwitchSelectionEndpoint();
+        Boolean ExpandSelectionToWord();
         void ClearBuffer(ClearBufferType clearType);
         void Close();
         Windows.Foundation.Size CharacterDimensions { get; };

src/cascadia/TerminalCore/Terminal.hpp

@@ -281,6 +281,7 @@ class Microsoft::Terminal::Core::Terminal final :
     void SelectAll();
     SelectionInteractionMode SelectionMode() const noexcept;
     void SwitchSelectionEndpoint();
+    void ExpandSelectionToWord();
     void ToggleMarkMode();
     void SelectHyperlink(const SearchDirection dir);
     bool SelectionIsTargetingUrl() const noexcept;

src/cascadia/TerminalCore/TerminalSelection.cpp

@@ -340,6 +340,16 @@ void Terminal::SwitchSelectionEndpoint()
     }
 }
 
+void Terminal::ExpandSelectionToWord()
+{
+    if (IsSelectionActive())
+    {
+        const auto& buffer = _activeBuffer();
+        _selection->start = buffer.GetWordStart(_selection->start, _wordDelimiters);
+        _selection->end = buffer.GetWordEnd(_selection->end, _wordDelimiters);
+    }
+}
+
 // Method Description:
 // - selects the next/previous hyperlink, if one is available
 // Arguments:

src/cascadia/TerminalSettingsModel/ActionAndArgs.cpp

@@ -84,6 +84,7 @@ static constexpr std::string_view SelectAllKey{ "selectAll" };
 static constexpr std::string_view MarkModeKey{ "markMode" };
 static constexpr std::string_view ToggleBlockSelectionKey{ "toggleBlockSelection" };
 static constexpr std::string_view SwitchSelectionEndpointKey{ "switchSelectionEndpoint" };
+static constexpr std::string_view ExpandSelectionToWordKey{ "expandSelectionToWord" };
 
 static constexpr std::string_view ActionKey{ "action" };
 
@@ -404,6 +405,7 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
                 { ShortcutAction::MarkMode, RS_(L"MarkModeCommandKey") },
                 { ShortcutAction::ToggleBlockSelection, RS_(L"ToggleBlockSelectionCommandKey") },
                 { ShortcutAction::SwitchSelectionEndpoint, RS_(L"SwitchSelectionEndpointCommandKey") },
+                { ShortcutAction::ExpandSelectionToWord, RS_(L"ExpandSelectionToWordCommandKey") },
             };
         }();
 

src/cascadia/TerminalSettingsModel/AllShortcutActions.h

@@ -97,6 +97,7 @@
     ON_ALL_ACTIONS(MarkMode)                \
     ON_ALL_ACTIONS(ToggleBlockSelection)    \
     ON_ALL_ACTIONS(SwitchSelectionEndpoint) \
+    ON_ALL_ACTIONS(ExpandSelectionToWord)   \
     ON_ALL_ACTIONS(CloseOtherPanes)
 
 #define ALL_SHORTCUT_ACTIONS_WITH_ARGS             \

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

@@ -567,6 +567,9 @@
   <data name="SwitchSelectionEndpointCommandKey" xml:space="preserve">
     <value>Switch selection endpoint</value>
   </data>
+  <data name="ExpandSelectionToWordCommandKey" xml:space="preserve">
+    <value>Expand selection to word</value>
+  </data>
   <data name="CloseOtherPanesCommandKey" xml:space="preserve">
     <value>Close all other panes</value>
   </data>

src/cascadia/TerminalSettingsModel/defaults.json

@@ -428,6 +428,7 @@
         { "command": "markMode", "keys": "ctrl+shift+m" },
         { "command": "toggleBlockSelection" },
         { "command": "switchSelectionEndpoint" },
+        { "command": "expandSelectionToWord" },
 
         // Scrollback
         { "command": "scrollDown", "keys": "ctrl+shift+down" },