Restore the original word-wise movement behavior

src/host/cmdline.cpp

@@ -2,29 +2,16 @@
 // Licensed under the MIT license.
 
 #include "precomp.h"
-
 #include "cmdline.h"
 
-#include "_output.h"
-#include "output.h"
-#include "stream.h"
-#include "_stream.h"
-#include "dbcs.h"
-#include "handle.h"
-#include "misc.h"
-#include "../types/inc/convert.hpp"
-#include "srvinit.h"
-
-#include "ApiRoutines.h"
-
 #include "../interactivity/inc/ServiceLocator.hpp"
 
 #pragma hdrstop
 using Microsoft::Console::Interactivity::ServiceLocator;
 
 // Routine Description:
 // - Detects Word delimiters
-bool IsWordDelim(const wchar_t wch)
+bool IsWordDelim(const wchar_t wch) noexcept
 {
     // the space character is always a word delimiter. Do not add it to the WordDelimiters global because
     // that contains the user configurable word delimiters only.
@@ -33,14 +20,27 @@ bool IsWordDelim(const wchar_t wch)
         return true;
     }
     const auto& delimiters = ServiceLocator::LocateGlobals().WordDelimiters;
-    if (delimiters.empty())
-    {
-        return false;
-    }
     return std::ranges::find(delimiters, wch) != delimiters.end();
 }
 
-bool IsWordDelim(const std::wstring_view charData)
+bool IsWordDelim(const std::wstring_view& charData) noexcept
 {
     return charData.size() == 1 && IsWordDelim(charData.front());
 }
+
+// Returns a truthy value for delimiters and 0 otherwise.
+// The distinction between whitespace and other delimiters allows us to
+// implement Windows' inconsistent, but classic, word-wise navigation.
+int DelimiterClass(wchar_t wch) noexcept
+{
+    if (wch == L' ')
+    {
+        return 1;
+    }
+    const auto& delimiters = ServiceLocator::LocateGlobals().WordDelimiters;
+    if (std::find(delimiters.begin(), delimiters.end(), wch) != delimiters.end())
+    {
+        return 2;
+    }
+    return 0;
+}

src/host/cmdline.h

@@ -6,5 +6,6 @@
 #include "screenInfo.hpp"
 
 // Word delimiters
-bool IsWordDelim(const wchar_t wch);
-bool IsWordDelim(const std::wstring_view charData);
+bool IsWordDelim(wchar_t wch) noexcept;
+bool IsWordDelim(const std::wstring_view& charData) noexcept;
+int DelimiterClass(wchar_t wch) noexcept;

src/host/readDataCooked.cpp

@@ -366,11 +366,13 @@ void COOKED_READ_DATA::_handleVkey(uint16_t vkey, DWORD modifiers)
         {
             if (ctrlPressed)
             {
-                // This would ideally use GraphemePrev() as well, but IsWordDelim() hasn't been refactored yet.
-                // Seek to the preceding left-hand word boundary.
-                // (The boundary between a non-word on the left and word on the right.)
                 --_bufferCursor;
-                while (_bufferCursor != 0 && (!IsWordDelim(_buffer[_bufferCursor - 1]) || IsWordDelim(_buffer[_bufferCursor])))
+                while (_bufferCursor != 0 && _buffer[_bufferCursor] == L' ')
+                {
+                    --_bufferCursor;
+                }
+                const auto dc = DelimiterClass(_buffer[_bufferCursor]);
+                while (_bufferCursor != 0 && DelimiterClass(_buffer[_bufferCursor - 1]) == dc)
                 {
                     --_bufferCursor;
                 }
@@ -388,11 +390,13 @@ void COOKED_READ_DATA::_handleVkey(uint16_t vkey, DWORD modifiers)
         {
             if (ctrlPressed && vkey == VK_RIGHT)
             {
-                // This would ideally use GraphemeNext() as well, but IsWordDelim() hasn't been refactored yet.
-                // Seek to the preceding left-hand word boundary.
-                // (The boundary between a non-word on the left and word on the right.)
                 ++_bufferCursor;
-                while (_bufferCursor != _buffer.size() && (!IsWordDelim(_buffer[_bufferCursor - 1]) || IsWordDelim(_buffer[_bufferCursor])))
+                const auto dc = DelimiterClass(_buffer[_bufferCursor - 1]);
+                while (_bufferCursor != _buffer.size() && dc == DelimiterClass(_buffer[_bufferCursor]))
+                {
+                    ++_bufferCursor;
+                }
+                while (_bufferCursor != _buffer.size() && _buffer[_bufferCursor] == L' ')
                 {
                     ++_bufferCursor;
                 }