patch 9.0.0707: with 'smoothscroll' cursor position not adjusted in long line

Problem:    With 'smoothscroll' and 'scrolloff' non-zero the cursor position
            is not properly adjusted in a long line.
Solution:   Move the cursor further up or down in the line.

src/move.c

@@ -1605,9 +1605,12 @@ scrolldown(
 
     if (curwin->w_cursor.lnum == curwin->w_topline && do_sms)
     {
+	long	so = curwin->w_p_so >= 0 ? curwin->w_p_so : p_so;
+	int	scrolloff_cols = so == 0 ? 0 : width1 + (so - 1) * width2;
+
 	// make sure the cursor is in the visible text
 	validate_virtcol();
-	int col = curwin->w_virtcol - curwin->w_skipcol;
+	int col = curwin->w_virtcol - curwin->w_skipcol + scrolloff_cols;
 	int row = 0;
 	if (col >= width1)
 	{
@@ -1620,8 +1623,11 @@ scrolldown(
 	    col = col % width2;
 	}
 	if (row >= curwin->w_height)
-	    coladvance(curwin->w_virtcol
+	{
-				      - (row - curwin->w_height + 1) * width2);
+	    curwin->w_curswant = curwin->w_virtcol
+				       - (row - curwin->w_height + 1) * width2;
+	    coladvance(curwin->w_curswant);
+	}
     }
 }
 
@@ -1748,19 +1754,24 @@ scrollup(
     if (curwin->w_cursor.lnum == curwin->w_topline
 					    && do_sms && curwin->w_skipcol > 0)
     {
-	// make sure the cursor is in a visible part of the line
+	int	width1 = curwin->w_width - curwin_col_off();
+	int	width2 = width1 + curwin_col_off2();
+	long	so = curwin->w_p_so >= 0 ? curwin->w_p_so : p_so;
+	int	scrolloff_cols = so == 0 ? 0 : width1 + (so - 1) * width2;
+
+	// Make sure the cursor is in a visible part of the line, taking
+	// 'scrolloff' into account, but using screen lines.
 	validate_virtcol();
-	if (curwin->w_virtcol < curwin->w_skipcol + 3)
+	if (curwin->w_virtcol < curwin->w_skipcol + 3 + scrolloff_cols)
 	{
-	    int	    width1 = curwin->w_width - curwin_col_off();
-	    int	    width2 = width1 + curwin_col_off2();
 	    colnr_T col = curwin->w_virtcol;
 
 	    if (col < width1)
 		col += width1;
-	    while (col < curwin->w_skipcol + 3)
+	    while (col < curwin->w_skipcol + 3 + scrolloff_cols)
 		col += width2;
-	    coladvance(col);
+	    curwin->w_curswant = col;
+	    coladvance(curwin->w_curswant);
 	}
     }
 }

src/testdir/dumps/Test_smooth_long_6.dump

@@ -0,0 +1,6 @@
+|<+0#4040ff13#ffffff0@2|t+0#0000000&|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t
+|h| |l|o|t|s| |o|f> |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o
+|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o
+|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e
+|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w
+| @21|3|,|9|0| @9|B|o|t| 

src/testdir/dumps/Test_smooth_long_7.dump

@@ -0,0 +1,6 @@
+|<+0#4040ff13#ffffff0@2|t+0#0000000&|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t
+|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o
+|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o
+|f| |t|e|x|t| |w|i>t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e
+|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w
+| @21|3|,|1|7|0| @8|B|o|t| 

src/testdir/dumps/Test_smooth_long_8.dump

@@ -0,0 +1,6 @@
+|<+0#4040ff13#ffffff0@2|t+0#0000000&|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t
+|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o
+|t|s| |o|f| |t|e|x>t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o
+|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e
+|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w
+| @21|3|,|1|3|0| @8|B|o|t| 

src/testdir/dumps/Test_smooth_long_9.dump

@@ -0,0 +1,6 @@
+|<+0#4040ff13#ffffff0@2|o+0#0000000&|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o
+|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o
+|f| |t|e|x|t| |w|i>t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e
+|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w
+|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| |l|o|t|s| |o|f| |t|e|x|t| |w|i|t|h| 
+@22|3|,|1|7|0| @8|B|o|t| 

src/testdir/test_scroll_opt.vim

@@ -223,6 +223,28 @@ func Test_smoothscroll_wrap_long_line()
   call term_sendkeys(buf, "\<C-Y>")
   call VerifyScreenDump(buf, 'Test_smooth_long_5', {})
 
+  " 'scrolloff' set to 1, scrolling up, cursor moves screen line down
+  call term_sendkeys(buf, ":set scrolloff=1\<CR>")
+  call term_sendkeys(buf, "10|\<C-E>")
+  call VerifyScreenDump(buf, 'Test_smooth_long_6', {})
+  
+  " 'scrolloff' set to 1, scrolling down, cursor moves screen line up
+  call term_sendkeys(buf, "\<C-E>")
+  call term_sendkeys(buf, "gjgj")
+  call term_sendkeys(buf, "\<C-Y>")
+  call VerifyScreenDump(buf, 'Test_smooth_long_7', {})
+  
+  " 'scrolloff' set to 2, scrolling up, cursor moves screen line down
+  call term_sendkeys(buf, ":set scrolloff=2\<CR>")
+  call term_sendkeys(buf, "10|\<C-E>")
+  call VerifyScreenDump(buf, 'Test_smooth_long_8', {})
+  
+  " 'scrolloff' set to 2, scrolling down, cursor moves screen line up
+  call term_sendkeys(buf, "\<C-E>")
+  call term_sendkeys(buf, "gj")
+  call term_sendkeys(buf, "\<C-Y>")
+  call VerifyScreenDump(buf, 'Test_smooth_long_9', {})
+  
   call StopVimInTerminal(buf)
 endfunc
 

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    707,
 /**/
     706,
 /**/