Add an experimental setting for moving the cursor with the mouse

src/buffer/out/textBuffer.cpp

@@ -246,6 +246,27 @@ til::CoordType TextBuffer::TotalRowCount() const noexcept
     return _height;
 }
 
+// Method Description:
+// - Gets the number of glyphs in the buffer between two points.
+// - IMPORTANT: Make sure that start is before end, or this will never return!
+// Arguments:
+// - start - The starting point of the range to get the glyph count for.
+// - end - The ending point of the range to get the glyph count for.
+// Return Value:
+// - The number of glyphs in the buffer between the two points.
+size_t TextBuffer::GetCellDistance(const til::point from, const til::point to) const
+{
+    auto startCell = GetCellDataAt(from);
+    const auto endCell = GetCellDataAt(to);
+    auto delta = 0;
+    while (startCell != endCell)
+    {
+        ++startCell;
+        ++delta;
+    }
+    return delta;
+}
+
 // Routine Description:
 // - Retrieves read-only text iterator at the given buffer location
 // Arguments:

src/buffer/out/textBuffer.hpp

@@ -131,6 +131,8 @@ class TextBuffer final
     TextBufferTextIterator GetTextLineDataAt(const til::point at) const;
     TextBufferTextIterator GetTextDataAt(const til::point at, const Microsoft::Console::Types::Viewport limit) const;
 
+    size_t GetCellDistance(const til::point from, const til::point to) const;
+
     static size_t GraphemeNext(const std::wstring_view& chars, size_t position) noexcept;
     static size_t GraphemePrev(const std::wstring_view& chars, size_t position) noexcept;
 

src/cascadia/TerminalControl/ControlCore.cpp

@@ -1447,7 +1447,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                                                             viewHeight,
                                                             bufferSize) };
 
-        if (_inUnitTests) [[unlikely]]
+        if (_inUnitTests)
+            [[unlikely]]
         {
             _ScrollPositionChangedHandlers(*this, update);
         }
@@ -1751,7 +1752,55 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             _terminal->MultiClickSelection(terminalPosition, mode);
             selectionNeedsToBeCopied = true;
         }
-        _updateSelectionUI();
+        else if (_settings->MoveCursorWithMouse()) // This is also mode==Char && !shiftEnabled
+        {
+            // If we're handling a single left click, without shift pressed, and
+            // outside mouse mode, AND the user has MoveCursorWithMouse turned
+            // on, let's try to move the cursor.
+            //
+            // We'll only move the cursor if the user has clicked after the last
+            // mark, if there is one. That means the user also needs to set up
+            // shell integration to enable this feature.
+            //
+            // As noted in GH #8573, there's plenty of edge cases with this
+            // approach, but it's good enough to bring value to 90% of use cases.
+            const auto cursorPos{ _terminal->GetCursorPosition() };
+
+            // Does the current buffer line have a mark on it?
+            const auto& marks{ _terminal->GetScrollMarks() };
+            if (!marks.empty())
+            {
+                const auto& last{ marks.back() };
+                const auto [start, end] = last.GetExtent();
+                if (terminalPosition >= end)
+                {
+                    // Get the distance between the cursor and the click, in cells.
+                    const auto bufferSize = _terminal->GetTextBuffer().GetSize();
+
+                    // First, make sure to iterate from the first point to the
+                    // second. The user may have clicked _earlier_ in the
+                    // buffer!
+                    auto goRight = terminalPosition > cursorPos;
+                    const auto startPoint = goRight ? cursorPos : terminalPosition;
+                    const auto endPoint = goRight ? terminalPosition : cursorPos;
+
+                    const auto delta = _terminal->GetTextBuffer().GetCellDistance(startPoint, endPoint);
+
+                    const WORD key = goRight ? VK_RIGHT : VK_LEFT;
+                    // Send an up and a down once per cell. This won't
+                    // accurately handle wide characters, or continuation
+                    // prompts, or cases where a single escape character in the
+                    // command (e.g. ^[) takes up two cells.
+                    for (size_t i = 0u; i < delta; i++)
+                    {
+                        _terminal->SendKeyEvent(key, 0, {}, true);
+                        _terminal->SendKeyEvent(key, 0, {}, false);
+                    }
+                }
+            }
+
+            _updateSelectionUI();
+        }
     }
 
     // Method Description:

src/cascadia/TerminalControl/IControlSettings.idl

@@ -61,5 +61,6 @@ namespace Microsoft.Terminal.Control
         Boolean ShowMarks { get; };
         Boolean UseBackgroundImageForWindow { get; };
         Boolean RightClickContextMenu { get; };
+        Boolean MoveCursorWithMouse { get; };
     };
 }

src/cascadia/TerminalSettingsModel/MTSMSettings.h

@@ -68,6 +68,12 @@ Author(s):
     X(bool, IsolatedMode, "compatibility.isolatedMode", false)                                                                                                                                        \
     X(hstring, SearchWebDefaultQueryUrl, "searchWebDefaultQueryUrl", L"https://www.bing.com/search?q=%22%s%22")
 
+// Also add these settings to:
+// * Profile.idl
+// * TerminalSettings.h
+// * TerminalSettings.cpp: TerminalSettings::_ApplyProfileSettings
+// * IControlSettings.idl or ICoreSettings.idl
+// * ControlProperties.h
 #define MTSM_PROFILE_SETTINGS(X)                                                                                                                               \
     X(int32_t, HistorySize, "historySize", DEFAULT_HISTORY_SIZE)                                                                                               \
     X(bool, SnapOnInput, "snapOnInput", true)                                                                                                                  \
@@ -90,7 +96,8 @@ Author(s):
     X(bool, Elevate, "elevate", false)                                                                                                                         \
     X(bool, VtPassthrough, "experimental.connection.passthroughMode", false)                                                                                   \
     X(bool, AutoMarkPrompts, "experimental.autoMarkPrompts", false)                                                                                            \
-    X(bool, ShowMarks, "experimental.showMarksOnScrollbar", false)
+    X(bool, ShowMarks, "experimental.showMarksOnScrollbar", false)                                                                                             \
+    X(bool, MoveCursorWithMouse, "experimental.moveCursorWithMouse", false)
 
 // Intentionally omitted Profile settings:
 // * Name

src/cascadia/TerminalSettingsModel/Profile.idl

@@ -94,5 +94,6 @@ namespace Microsoft.Terminal.Settings.Model
         INHERITABLE_PROFILE_SETTING(Boolean, ShowMarks);
 
         INHERITABLE_PROFILE_SETTING(Boolean, RightClickContextMenu);
+        INHERITABLE_PROFILE_SETTING(Boolean, MoveCursorWithMouse);
     }
 }

src/cascadia/TerminalSettingsModel/TerminalSettings.cpp

@@ -325,6 +325,8 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
         _ShowMarks = Feature_ScrollbarMarks::IsEnabled() && profile.ShowMarks();
 
         _RightClickContextMenu = profile.RightClickContextMenu();
+
+        _MoveCursorWithMouse = profile.MoveCursorWithMouse();
     }
 
     // Method Description:

src/cascadia/TerminalSettingsModel/TerminalSettings.h

@@ -164,6 +164,7 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
         INHERITABLE_SETTING(Model::TerminalSettings, bool, AutoMarkPrompts, false);
         INHERITABLE_SETTING(Model::TerminalSettings, bool, ShowMarks, false);
         INHERITABLE_SETTING(Model::TerminalSettings, bool, RightClickContextMenu, false);
+        INHERITABLE_SETTING(Model::TerminalSettings, bool, MoveCursorWithMouse, false);
 
     private:
         std::optional<std::array<Microsoft::Terminal::Core::Color, COLOR_TABLE_SIZE>> _ColorTable;

src/cascadia/inc/ControlProperties.h

@@ -47,7 +47,8 @@
     X(winrt::hstring, StartingTitle)                                                                              \
     X(bool, DetectURLs, true)                                                                                     \
     X(bool, VtPassthrough, false)                                                                                 \
-    X(bool, AutoMarkPrompts)
+    X(bool, AutoMarkPrompts)                                                                                      \
+    X(bool, MoveCursorWithMouse, false)
 
 // --------------------------- Control Settings ---------------------------
 //  All of these settings are defined in IControlSettings.