patch 9.0.0775: MS-Windows: mouse scrolling not supported in the console

Problem:    MS-Windows: mouse scrolling not supported in the console.
Solution:   Add event handling for mouse scroll events. (Christopher
            Plewright, closes #11374)

.gitignore

@@ -44,6 +44,8 @@ gvimext.lib
 gvim.lib
 runtime/doc/uganda.nsis.txt
 nsis/icons/*
+/vim90/
+.vscode/
 
 # NetBeans
 nbproject/*

src/INSTALLpc.txt

@@ -896,53 +896,53 @@ work on MS-DOS because of the limited amount of memory available.
 After you've built the Vim binaries as described above, you're ready to
 install Vim on your system.  However, if you've obtained the Vim sources
 using Git, Mercurial or by downloading them as a unix tar file, you must
-first create a "vim82" directory.  If you instead downloaded the sources as
+first create a "vim90" directory.  If you instead downloaded the sources as
 zip files, you can skip this setup as the zip archives already have the
 correct directory structure.
 
-  A.  Create a Vim "runtime" subdirectory named "vim82"
+  A.  Create a Vim "runtime" subdirectory named "vim90"
   -----------------------------------------------------
   If you obtained your Vim sources as zip files, you can skip this step.
   Otherwise, continue reading.
 
   Go to the directory that contains the Vim "src" and "runtime"
-  directories and create a new subdirectory named "vim82".
+  directories and create a new subdirectory named "vim90".
 
-  Copy the "runtime" files into "vim82":
-     copy runtime\* vim82
-     xcopy /s runtime\* vim82
+  Copy the "runtime" files into "vim90":
+     copy runtime\* vim90
+     xcopy /s runtime\* vim90
 
-  B.  Copy the new binaries into the "vim82" directory
+  B.  Copy the new binaries into the "vim90" directory
   ----------------------------------------------------
   Regardless of how you installed the Vim sources, you need to copy the
-  new binaries you created above into "vim82":
+  new binaries you created above into "vim90":
 
-     copy src\*.exe vim82
-     copy src\tee\tee.exe vim82
-     copy src\xxd\xxd.exe vim82
+     copy src\*.exe vim90
+     copy src\tee\tee.exe vim90
+     copy src\xxd\xxd.exe vim90
 
   To install the "Edit with Vim" popup menu, you need both 32-bit and 64-bit
-  versions of gvimext.dll.  They should be copied to "vim82\GvimExt32" and
-  "vim82\GvimExt64" respectively.
+  versions of gvimext.dll.  They should be copied to "vim90\GvimExt32" and
+  "vim90\GvimExt64" respectively.
   First, build the 32-bit version, then:
 
-     mkdir vim82\GvimExt32
-     copy src\GvimExt\gvimext.dll vim82\GvimExt32
+     mkdir vim90\GvimExt32
+     copy src\GvimExt\gvimext.dll vim90\GvimExt32
 
   Next, clean the 32-bit version and build the 64-bit version, then:
 
-     mkdir vim82\GvimExt64
-     copy src\GvimExt\gvimext.dll vim82\GvimExt64
+     mkdir vim90\GvimExt64
+     copy src\GvimExt\gvimext.dll vim90\GvimExt64
 
-  C.  Copy gettext and iconv DLLs into the "vim82" directory
+  C.  Copy gettext and iconv DLLs into the "vim90" directory
   ----------------------------------------------------------
   Get gettext and iconv DLLs from the following site:
      https://github.com/mlocati/gettext-iconv-windows/releases
   Both 64- and 32-bit versions are needed.
   Download the files gettextX.X.X.X-iconvX.XX-shared-{32,64}.zip, extract
   DLLs and place them as follows:
 
-        vim82\
+        vim90\
             |   libintl-8.dll
             |   libiconv-2.dll
             |   libgcc_s_sjlj-1.dll     (only for 32-bit)
@@ -956,18 +956,18 @@ correct directory structure.
                 libintl-8.dll
                 libiconv-2.dll
 
-  The DLLs in the "vim82" should be the same bitness with the (g)vim.exe.
+  The DLLs in the "vim90" should be the same bitness with the (g)vim.exe.
 
-  D.  Move the "vim82" directory into the Vim installation subdirectory
+  D.  Move the "vim90" directory into the Vim installation subdirectory
   ---------------------------------------------------------------------
-  Move the "vim82" subdirectory into the subdirectory where you want Vim
+  Move the "vim90" subdirectory into the subdirectory where you want Vim
   to be installed.  Typically, this subdirectory will be named "vim".
-  If you already have a "vim82" subdirectory in "vim", delete it first
+  If you already have a "vim90" subdirectory in "vim", delete it first
   by running its uninstall.exe program.
 
   E.  Install Vim
   ---------------
-  "cd" to your Vim installation subdirectory "vim\vim82" and run the
+  "cd" to your Vim installation subdirectory "vim\vim90" and run the
   "install.exe" program.  It will ask you a number of questions about
   how you would like to have your Vim setup.  Among these are:
   - You can tell it to write a "_vimrc" file with your preferences in the

src/os_win32.c

@@ -1231,6 +1231,100 @@ mch_bevalterm_changed(void)
 }
 # endif
 
+
+/*
+ * Win32 console mouse scroll event handler.
+ * Loosely based on the _OnMouseWheel() function in gui_w32.c
+ *
+ * This encodes the mouse scroll direction and keyboard modifiers into
+ * g_nMouseClick, and the mouse position into g_xMouse and g_yMouse
+ *
+ * The direction of the scroll is decoded from two fields of the win32 console
+ * mouse event record;
+ *    1. The axis - vertical or horizontal flag - from dwEventFlags, and
+ *    2. The sign - positive or negative (aka delta flag) - from dwButtonState
+ *
+ * When scroll axis is HORIZONTAL
+ *    -  If the high word of the dwButtonState member contains a positive
+ *	 value, the wheel was rotated to the right.
+ *    -  Otherwise, the wheel was rotated to the left.
+ * When scroll axis is VERTICAL
+ *    -  If the high word of the dwButtonState member contains a positive value,
+ *       the wheel was rotated forward, away from the user.
+ *    -  Otherwise, the wheel was rotated backward, toward the user.
+ */
+    static void
+decode_mouse_wheel(MOUSE_EVENT_RECORD *pmer)
+{
+    win_T   *wp;
+    int	    horizontal = (pmer->dwEventFlags == MOUSE_HWHEELED);
+    int	    zDelta = pmer->dwButtonState;
+
+    g_xMouse = pmer->dwMousePosition.X;
+    g_yMouse = pmer->dwMousePosition.Y;
+
+#ifdef FEAT_PROP_POPUP
+    int lcol;
+    int lrow;
+    lcol = g_xMouse;
+    lrow = g_yMouse;
+    wp = mouse_find_win(&lrow, &lcol, FAIL_POPUP);
+    if (wp != NULL && popup_is_popup(wp))
+    {
+	g_nMouseClick = -1;
+	cmdarg_T cap;
+	oparg_T oa;
+	CLEAR_FIELD(cap);
+	clear_oparg(&oa);
+	cap.oap = &oa;
+	if (horizontal)
+	{
+	    cap.arg = zDelta < 0 ? MSCR_LEFT : MSCR_RIGHT;
+	    cap.cmdchar = zDelta < 0 ? K_MOUSELEFT : K_MOUSERIGHT;
+	}
+	else
+	{
+	    cap.cmdchar = zDelta < 0 ? K_MOUSEUP : K_MOUSEDOWN;
+	    cap.arg = zDelta < 0 ? MSCR_UP : MSCR_DOWN;
+	}
+
+	// Mouse hovers over popup window, scroll it if possible.
+	mouse_row = wp->w_winrow;
+	mouse_col = wp->w_wincol;
+	nv_mousescroll(&cap);
+	update_screen(0);
+	setcursor();
+	out_flush();
+	return;
+    }
+#endif
+    mouse_col = g_xMouse;
+    mouse_row = g_yMouse;
+
+    char_u modifiers = 0;
+    char_u direction = 0;
+
+    // Decode the direction into an event that Vim can process
+    if (horizontal)
+	direction = zDelta >= 0 ? KE_MOUSELEFT : KE_MOUSERIGHT;
+    else
+	direction = zDelta >= 0 ? KE_MOUSEDOWN : KE_MOUSEUP;
+
+    // Decode the win32 console key modifers into Vim mouse modifers.
+    if (pmer->dwControlKeyState & SHIFT_PRESSED)
+	modifiers |= MOD_MASK_SHIFT; //MOUSE_SHIFT;
+    if (pmer->dwControlKeyState & (RIGHT_CTRL_PRESSED | LEFT_CTRL_PRESSED))
+	modifiers |= MOD_MASK_CTRL; //MOUSE_CTRL;
+    if (pmer->dwControlKeyState & (RIGHT_ALT_PRESSED  | LEFT_ALT_PRESSED))
+	modifiers |= MOD_MASK_ALT; // MOUSE_ALT;
+
+    // add (bitwise or) the scroll direction and the key modifier chars
+    // together.
+    g_nMouseClick = ((direction << 8) | modifiers);
+
+    return;
+}
+
 /*
  * Decode a MOUSE_EVENT.  If it's a valid event, return MOUSE_LEFT,
  * MOUSE_MIDDLE, or MOUSE_RIGHT for a click; MOUSE_DRAG for a mouse
@@ -1304,6 +1398,13 @@ decode_mouse_event(
     if (g_nMouseClick != -1)
 	return TRUE;
 
+    if (pmer->dwEventFlags == MOUSE_WHEELED
+				       || pmer->dwEventFlags == MOUSE_HWHEELED)
+    {
+	decode_mouse_wheel(pmer);
+	return TRUE;  // we now should have a mouse scroll in g_nMouseClick
+    }
+
     nButton = -1;
     g_xMouse = pmer->dwMousePosition.X;
     g_yMouse = pmer->dwMousePosition.Y;
@@ -1939,12 +2040,34 @@ mch_inchar(
 		fprintf(fdDump, "{%02x @ %d, %d}",
 			g_nMouseClick, g_xMouse, g_yMouse);
 # endif
-	    typeahead[typeaheadlen++] = ESC + 128;
-	    typeahead[typeaheadlen++] = 'M';
-	    typeahead[typeaheadlen++] = g_nMouseClick;
-	    typeahead[typeaheadlen++] = g_xMouse + '!';
-	    typeahead[typeaheadlen++] = g_yMouse + '!';
-	    g_nMouseClick = -1;
+	    char_u modifiers = ((char_u *)(&g_nMouseClick))[0];
+	    char_u scroll_dir = ((char_u *)(&g_nMouseClick))[1];
+
+	    if (scroll_dir == KE_MOUSEDOWN
+		    || scroll_dir == KE_MOUSEUP
+		    || scroll_dir == KE_MOUSELEFT
+		    || scroll_dir == KE_MOUSERIGHT)
+	    {
+		if (modifiers > 0)
+		{
+		    typeahead[typeaheadlen++] = CSI;
+		    typeahead[typeaheadlen++] = KS_MODIFIER;
+		    typeahead[typeaheadlen++] = modifiers;
+		}
+		typeahead[typeaheadlen++] = CSI;
+		typeahead[typeaheadlen++] = KS_EXTRA;
+		typeahead[typeaheadlen++] = scroll_dir;
+		g_nMouseClick = -1;
+	    }
+	    else
+	    {
+		typeahead[typeaheadlen++] = ESC + 128;
+		typeahead[typeaheadlen++] = 'M';
+		typeahead[typeaheadlen++] = g_nMouseClick;
+		typeahead[typeaheadlen++] = g_xMouse + '!';
+		typeahead[typeaheadlen++] = g_yMouse + '!';
+		g_nMouseClick = -1;
+	    }
 	}
 	else
 	{
@@ -8361,7 +8484,7 @@ stop_timeout(void)
 {
     if (timer_active)
     {
-        BOOL ret = DeleteTimerQueueTimer(NULL, timer_handle, NULL);
+	BOOL ret = DeleteTimerQueueTimer(NULL, timer_handle, NULL);
 	timer_active = FALSE;
 	if (!ret && GetLastError() != ERROR_IO_PENDING)
 	{

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    775,
 /**/
     774,
 /**/