patch 8.2.2084: CTRL-V U doesn't work to enter a Unicode character

Problem:    CTRL-V U doesn't work to enter a Unicode character when
            modifyOtherKeys is effective. (Ken Takata)
Solution:   Add a flag to get_literal() for the shift key. (closes #7413)

src/edit.c

@@ -1534,7 +1534,6 @@ ins_ctrl_v(void)
 {
     int		c;
     int		did_putchar = FALSE;
-    int		prev_mod_mask = mod_mask;
 
     // may need to redraw when no more chars available now
     ins_redraw(FALSE);
@@ -1550,7 +1549,9 @@ ins_ctrl_v(void)
     add_to_showcmd_c(Ctrl_V);
 #endif
 
-    c = get_literal();
+    // Do not change any modifyOtherKeys ESC sequence to a normal key for
+    // CTRL-SHIFT-V.
+    c = get_literal(mod_mask & MOD_MASK_SHIFT);
     if (did_putchar)
 	// when the line fits in 'columns' the '^' is at the start of the next
 	// line and will not removed by the redraw
@@ -1559,11 +1560,6 @@ ins_ctrl_v(void)
     clear_showcmd();
 #endif
 
-    if ((c == ESC || c == CSI) && !(prev_mod_mask & MOD_MASK_SHIFT))
-	// Using CTRL-V: Change any modifyOtherKeys ESC sequence to a normal
-	// key.  Don't do this for CTRL-SHIFT-V.
-	c = decodeModifyOtherKeys(c);
-
     insert_special(c, FALSE, TRUE);
 #ifdef FEAT_RIGHTLEFT
     revins_chars++;
@@ -1845,9 +1841,11 @@ del_char_after_col(int limit_col UNUSED)
  * A one, two or three digit decimal number is interpreted as its byte value.
  * If one or two digits are entered, the next character is given to vungetc().
  * For Unicode a character > 255 may be returned.
+ * If "noReduceKeys" is TRUE do not change any modifyOtherKeys ESC sequence
+ * into a normal key, return ESC.
  */
     int
-get_literal(void)
+get_literal(int noReduceKeys)
 {
     int		cc;
     int		nc;
@@ -1878,6 +1876,9 @@ get_literal(void)
     for (;;)
     {
 	nc = plain_vgetc();
+	if ((nc == ESC || nc == CSI) && !noReduceKeys)
+	    nc = decodeModifyOtherKeys(nc);
+
 #ifdef FEAT_CMDL_INFO
 	if (!(State & CMDLINE) && MB_BYTE2LEN_CHECK(nc) == 1)
 	    add_to_showcmd(nc);
@@ -3812,8 +3813,7 @@ ins_ctrl_o(void)
 {
     if (State & VREPLACE_FLAG)
 	restart_edit = 'V';
-    else
+    else if (State & REPLACE_FLAG)
-	if (State & REPLACE_FLAG)
 	restart_edit = 'R';
     else
 	restart_edit = 'I';

src/ex_getln.c

@@ -2206,13 +2206,14 @@ getcmdline_int(
 	case Ctrl_V:
 	case Ctrl_Q:
 		{
-		    int	 prev_mod_mask = mod_mask;
-
 		    ignore_drag_release = TRUE;
 		    putcmdline('^', TRUE);
-		    no_reduce_keys = TRUE;  //  don't merge modifyOtherKeys
+
-		    c = get_literal();	    // get next (two) character(s)
+		    // Get next (two) character(s).  Do not change any
-		    no_reduce_keys = FALSE;
+		    // modifyOtherKeys ESC sequence to a normal key for
+		    // CTRL-SHIFT-V.
+		    c = get_literal(mod_mask & MOD_MASK_SHIFT);
+
 		    do_abbr = FALSE;	    // don't do abbreviation now
 		    extra_char = NUL;
 		    // may need to remove ^ when composing char was typed
@@ -2223,13 +2224,6 @@ getcmdline_int(
 			msg_putchar(' ');
 			cursorcmd();
 		    }
-
-		    if ((c == ESC || c == CSI)
-					  && !(prev_mod_mask & MOD_MASK_SHIFT))
-			// Using CTRL-V: Change any modifyOtherKeys ESC
-			// sequence to a normal key.  Don't do this for
-			// CTRL-SHIFT-V.
-			c = decodeModifyOtherKeys(c);
 		}
 
 		break;

src/getchar.c

@@ -2580,11 +2580,10 @@ handle_mapping(
 						    typebuf.tb_off] == RM_YES))
 		&& !*timedout)
 	{
-	    keylen = check_termcode(max_mlen + 1,
+	    keylen = check_termcode(max_mlen + 1, NULL, 0, NULL);
-					       NULL, 0, NULL);
 
-	    // If no termcode matched but 'pastetoggle' matched partially it's
+	    // If no termcode matched but 'pastetoggle' matched partially
-	    // like an incomplete key sequence.
+	    // it's like an incomplete key sequence.
 	    if (keylen == 0 && save_keylen == KEYLEN_PART_KEY)
 		keylen = KEYLEN_PART_KEY;
 
@@ -3680,7 +3679,7 @@ getcmdkeycmd(
 	    // CTRL-V is followed by octal, hex or other characters, reverses
 	    // what AppendToRedobuffLit() does.
 	    no_reduce_keys = TRUE;  //  don't merge modifyOtherKeys
-	    c1 = get_literal();
+	    c1 = get_literal(TRUE);
 	    no_reduce_keys = FALSE;
 	}
 

src/normal.c

@@ -4927,7 +4927,7 @@ nv_replace(cmdarg_T *cap)
     if (cap->nchar == Ctrl_V)
     {
 	had_ctrl_v = Ctrl_V;
-	cap->nchar = get_literal();
+	cap->nchar = get_literal(FALSE);
 	// Don't redo a multibyte character with CTRL-V.
 	if (cap->nchar > DEL)
 	    had_ctrl_v = NUL;
@@ -5208,7 +5208,7 @@ nv_vreplace(cmdarg_T *cap)
 	else
 	{
 	    if (cap->extra_char == Ctrl_V)	// get another character
-		cap->extra_char = get_literal();
+		cap->extra_char = get_literal(FALSE);
 	    stuffcharReadbuff(cap->extra_char);
 	    stuffcharReadbuff(ESC);
 	    if (virtual_active())

src/proto/edit.pro

@@ -10,7 +10,7 @@ void display_dollar(colnr_T col);
 void undisplay_dollar(void);
 void truncate_spaces(char_u *line);
 void backspace_until_column(int col);
-int get_literal(void);
+int get_literal(int noReduceKeys);
 void insertchar(int c, int flags, int second_indent);
 void start_arrow(pos_T *end_insert_pos);
 int stop_arrow(void);

src/testdir/test_termcodes.vim

@@ -1966,6 +1966,16 @@ func RunTest_modifyOtherKeys(func)
   bwipe aaa
   bwipe bbb
 
+  " Ctrl-V X 33 is 3
+  call setline(1, '')
+  call feedkeys("a\<C-V>" .. a:func('X', 2) .. "33\<Esc>", 'Lx!')
+  call assert_equal("3", getline(1))
+
+  " Ctrl-V U 12345 is Unicode 12345
+  call setline(1, '')
+  call feedkeys("a\<C-V>" .. a:func('U', 2) .. "12345\<Esc>", 'Lx!')
+  call assert_equal("\U12345", getline(1))
+
   bwipe!
   set timeoutlen&
 endfunc

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2084,
 /**/
     2083,
 /**/