patch 8.2.2903: cursor position wrong on wrapped line with 'signcolumn'

Problem:    Cursor position wrong on wrapped line with 'signcolumn'.
Solution:   Don't add space for showbreak twice. (Christian Brabandt,
            closes #8262)

src/drawline.c

@@ -1981,6 +1981,12 @@ win_line(
 		    // TODO: is passing p for start of the line OK?
 		    n_extra = win_lbr_chartabsize(wp, line, p, (colnr_T)vcol,
 								    NULL) - 1;
+
+		    // We have just drawn the showbreak value, no need to add
+		    // space for it again
+		    if (vcol == vcol_sbr)
+			n_extra -= MB_CHARLEN(get_showbreak_value(wp));
+
 		    if (c == TAB && n_extra + col > wp->w_width)
 # ifdef FEAT_VARTABS
 			n_extra = tabstop_padding(vcol, wp->w_buffer->b_p_ts,

src/testdir/test_display.vim

@@ -334,4 +334,21 @@ func Test_fold_fillchars()
   set fillchars& fdc& foldmethod& foldenable&
 endfunc
 
+func Test_display_linebreak_breakat()
+  new
+  vert resize 25
+  let _breakat = &breakat
+  setl signcolumn=yes linebreak breakat=) showbreak=+\ 
+  call setline(1, repeat('x', winwidth(0) - 2) .. ')abc')
+  let lines = ScreenLines([1, 2], 25)
+  let expected = [
+          \ '  xxxxxxxxxxxxxxxxxxxxxxx',
+          \ '  + )abc                 '
+          \ ]
+  call assert_equal(expected, lines)
+  %bw!
+  let &breakat=_breakat
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2903,
 /**/
     2902,
 /**/