vim-patch:9.1.2017: getregionpos() depends on 'linebreak' setting (#37088)

Problem:  getregionpos() depends on 'linebreak' setting
Solution: Reset linebreak setting temporarily (McAuley Penney)

When a line is wrapped on word boundaries, getregionpos() may report a
different end column for a visual block than the cursor position used to
define the selection.

Update the blockwise calculation in getregionpos() to use the same
wrapping assumptions as visual block mode, so the reported region
matches the selection boundaries.

Add a regression test that forces wrapping and checks that the end
position stays consistent under "setlocal wrap" and "setlocal
linebreak".

closes: vim/vim#19006

8ea0e7205c

Co-authored-by: McAuley Penney <jacobmpenney@gmail.com>

src/nvim/eval/funcs.c

@@ -2281,8 +2281,10 @@ static int getregionpos(typval_T *argvars, typval_T *rettv, pos_T *p1, pos_T *p2
     }
   } else if (*region_type == kMTBlockWise) {
     colnr_T sc1, ec1, sc2, ec2;
+    const bool lbr_saved = reset_lbr();
     getvvcol(curwin, p1, &sc1, NULL, &ec1);
     getvvcol(curwin, p2, &sc2, NULL, &ec2);
+    restore_lbr(lbr_saved);
     oap->motion_type = kMTBlockWise;
     oap->inclusive = true;
     oap->op_type = OP_NOP;

src/nvim/ops.c

@@ -2077,7 +2077,7 @@ theend:
 
 /// Reset 'linebreak' and take care of side effects.
 /// @return  the previous value, to be passed to restore_lbr().
-static bool reset_lbr(void)
+bool reset_lbr(void)
 {
   if (!curwin->w_p_lbr) {
     return false;
@@ -2089,7 +2089,7 @@ static bool reset_lbr(void)
 }
 
 /// Restore 'linebreak' and take care of side effects.
-static void restore_lbr(bool lbr_saved)
+void restore_lbr(bool lbr_saved)
 {
   if (curwin->w_p_lbr || !lbr_saved) {
     return;

test/old/testdir/test_visual.vim

@@ -2839,4 +2839,73 @@ func Test_visual_block_pos_update()
   bw!
 endfunc
 
+" Test that blockwise end position matches getpos('.')
+" when 'wrap' and 'linebreak' are set
+func Test_getregionpos_block_linebreak_matches_getpos()
+  CheckFeature linebreak
+
+  new
+  setlocal buftype=
+  setlocal bufhidden=wipe
+  setlocal noswapfile
+
+  setlocal wrap
+  setlocal linebreak
+  setlocal breakat=\ \t
+  setlocal nonumber norelativenumber
+  setlocal signcolumn=no
+  setlocal foldcolumn=0
+
+  call setline(1, '1111111111 2222222222 3333333333 4444444444 5555555555 6666666666 7777777777 8888888888')
+
+  " Force wrapping deterministically by shrinking the screen width.
+  let save_columns = &columns
+  let moved = 0
+  for c in [30, 20, 15, 10]
+    execute 'set columns=' .. c
+    redraw!
+    normal! gg0
+    let row0 = winline()
+    normal! gj
+    let row1 = winline()
+    if row1 > row0
+      let moved = 1
+      break
+    endif
+  endfor
+  call assert_true(moved)
+
+  " Move a bit right so we are not at column 1, then go back up one screen line.
+  normal! 5l
+  normal! gk
+  let row2 = winline()
+  call assert_equal(row0, row2)
+
+  " Start Visual block and move down one screen line to the previous position.
+  execute "normal! \<C-V>"
+  normal! gj
+  let row3 = winline()
+  call assert_equal(row1, row3)
+
+  let p1 = getpos('v')
+  let p2 = getpos('.')
+
+  " Sanity: block selection is within the same wrapped buffer line.
+  call assert_equal(1, p1[1])
+  call assert_equal(1, p2[1])
+
+  " For blockwise region, getregionpos() should not report an end position
+  " different from the {pos2} we passed in.
+  let segs = getregionpos(p1, p2, #{ type: "\<C-V>", exclusive: v:false })
+
+  call assert_equal(1, len(segs))
+  let endp = segs[0][1]
+
+  call assert_equal(p2[1], endp[1])  " lnum
+  call assert_equal(p2[2], endp[2])  " col
+  call assert_equal(p2[3], endp[3])  " off
+
+  let &columns = save_columns
+  bw!
+endfunc
 " vim: shiftwidth=2 sts=2 expandtab