patch 9.0.0765: with a Visual block a put command column may go negative

Problem:    With a Visual block a put command column may go negative.
Solution:   Check that the column does not become negative.

src/register.c

@@ -1960,6 +1960,8 @@ do_put(
 	// adjust '] mark
 	curbuf->b_op_end.lnum = curwin->w_cursor.lnum - 1;
 	curbuf->b_op_end.col = bd.textcol + totlen - 1;
+	if (curbuf->b_op_end.col < 0)
+	    curbuf->b_op_end.col = 0;
 	curbuf->b_op_end.coladd = 0;
 	if (flags & PUT_CURSEND)
 	{

src/testdir/test_visual.vim

@@ -483,6 +483,18 @@ func Test_visual_block_put()
   bw!
 endfunc
 
+func Test_visual_block_put_invalid()
+  enew!
+  behave mswin
+  norm yy
+  norm v)Ps/^/	
+  " this was causing the column to become negative
+  silent norm ggv)P
+
+  bwipe!
+  behave xterm
+endfunc
+
 " Visual modes (v V CTRL-V) followed by an operator; count; repeating
 func Test_visual_mode_op()
   new

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    765,
 /**/
     764,
 /**/