Merge pull request #17382 from zeertzjq/vim-8.2.2342

vim-patch:8.2.2342: "char" functions may return wrong column in Insert mode

src/nvim/eval.c

@@ -8192,7 +8192,7 @@ char *save_tv_as_string(typval_T *tv, ptrdiff_t *const len, bool endnl)
 
 /// Convert the specified byte index of line 'lnum' in buffer 'buf' to a
 /// character index.  Works only for loaded buffers. Returns -1 on failure.
-/// The index of the first character is one.
+/// The index of the first byte and the first character is zero.
 int buf_byteidx_to_charidx(buf_T *buf, int lnum, int byteidx)
 {
   if (buf == NULL || buf->b_ml.ml_mfp == NULL) {
@@ -8206,15 +8206,29 @@ int buf_byteidx_to_charidx(buf_T *buf, int lnum, int byteidx)
   char_u *str = ml_get_buf(buf, lnum, false);
 
   if (*str == NUL) {
-    return 1;
+    return 0;
   }
 
-  return mb_charlen_len(str, byteidx + 1);
+  // count the number of characters
+  char_u *t = str;
+  int count;
+  for (count = 0; *t != NUL && t <= str + byteidx; count++) {
+    t += utfc_ptr2len(t);
+  }
+
+  // In insert mode, when the cursor is at the end of a non-empty line,
+  // byteidx points to the NUL character immediately past the end of the
+  // string. In this case, add one to the character count.
+  if (*t == NUL && byteidx != 0 && t == str + byteidx) {
+    count++;
+  }
+
+  return count - 1;
 }
 
 /// Convert the specified character index of line 'lnum' in buffer 'buf' to a
-/// byte index.  Works only for loaded buffers. Returns -1 on failure. The index
+/// byte index.  Works only for loaded buffers. Returns -1 on failure.
-/// of the first byte and the first character is one.
+/// The index of the first byte and the first character is zero.
 int buf_charidx_to_byteidx(buf_T *buf, int lnum, int charidx)
 {
   if (buf == NULL || buf->b_ml.ml_mfp == NULL) {
@@ -8233,7 +8247,7 @@ int buf_charidx_to_byteidx(buf_T *buf, int lnum, int charidx)
     t += utfc_ptr2len(t);
   }
 
-  return t - str + 1;
+  return t - str;
 }
 
 /// Translate a VimL object into a position
@@ -8315,7 +8329,7 @@ pos_T *var2fpos(const typval_T *const tv, const bool dollar_lnum, int *const ret
   if (name[0] == '.') {  // Cursor.
     pos = curwin->w_cursor;
     if (charcol) {
-      pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col) - 1;
+      pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col);
     }
     return &pos;
   }
@@ -8326,7 +8340,7 @@ pos_T *var2fpos(const typval_T *const tv, const bool dollar_lnum, int *const ret
       pos = curwin->w_cursor;
     }
     if (charcol) {
-      pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col) - 1;
+      pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col);
     }
     return &pos;
   }
@@ -8336,7 +8350,7 @@ pos_T *var2fpos(const typval_T *const tv, const bool dollar_lnum, int *const ret
       return NULL;
     }
     if (charcol) {
-      pp->col = buf_byteidx_to_charidx(curbuf, pp->lnum, pp->col) - 1;
+      pp->col = buf_byteidx_to_charidx(curbuf, pp->lnum, pp->col);
     }
     return pp;
   }
@@ -8423,7 +8437,7 @@ int list2fpos(typval_T *arg, pos_T *posp, int *fnump, colnr_T *curswantp, bool c
     if (buf == NULL || buf->b_ml.ml_mfp == NULL) {
       return FAIL;
     }
-    n = buf_charidx_to_byteidx(buf, posp->lnum, n);
+    n = buf_charidx_to_byteidx(buf, posp->lnum, n) + 1;
   }
   posp->col = n;
 

src/nvim/eval/funcs.c

@@ -1588,7 +1588,7 @@ static void set_cursorpos(typval_T *argvars, typval_T *rettv, bool charcol)
     line = tv_get_lnum(argvars);
     col = (long)tv_get_number_chk(&argvars[1], NULL);
     if (charcol) {
-      col = buf_charidx_to_byteidx(curbuf, line, col);
+      col = buf_charidx_to_byteidx(curbuf, line, col) + 1;
     }
     if (argvars[2].v_type != VAR_UNKNOWN) {
       coladd = (long)tv_get_number_chk(&argvars[2], NULL);
@@ -3327,7 +3327,7 @@ static void getpos_both(typval_T *argvars, typval_T *rettv, bool getcurpos, bool
     }
     if (fp != NULL && charcol) {
       pos = *fp;
-      pos.col = buf_byteidx_to_charidx(wp->w_buffer, pos.lnum, pos.col) - 1;
+      pos.col = buf_byteidx_to_charidx(wp->w_buffer, pos.lnum, pos.col);
       fp = &pos;
     }
   } else {

src/nvim/testdir/test_cursor_func.vim

@@ -123,11 +123,18 @@ func Test_screenpos_number()
   bwipe!
 endfunc
 
+" Save the visual start character position
 func SaveVisualStartCharPos()
   call add(g:VisualStartPos, getcharpos('v'))
   return ''
 endfunc
 
+" Save the current cursor character position in insert mode
+func SaveInsertCurrentCharPos()
+  call add(g:InsertCurrentPos, getcharpos('.'))
+  return ''
+endfunc
+
 " Test for the getcharpos() function
 func Test_getcharpos()
   call assert_fails('call getcharpos({})', 'E731:')
@@ -156,16 +163,29 @@ func Test_getcharpos()
   vnoremap <expr> <F3> SaveVisualStartCharPos()
   let g:VisualStartPos = []
   exe "normal 2G6lv$\<F3>ohh\<F3>o\<F3>"
-  call assert_equal([[0, 2, 7, 0], [0, 2, 9, 0], [0, 2, 5, 0]], g:VisualStartPos)
+  call assert_equal([[0, 2, 7, 0], [0, 2, 10, 0], [0, 2, 5, 0]], g:VisualStartPos)
   call assert_equal([0, 2, 9, 0], getcharpos('v'))
   let g:VisualStartPos = []
   exe "normal 3Gv$\<F3>o\<F3>"
-  call assert_equal([[0, 3, 1, 0], [0, 3, 1, 0]], g:VisualStartPos)
+  call assert_equal([[0, 3, 1, 0], [0, 3, 2, 0]], g:VisualStartPos)
   let g:VisualStartPos = []
   exe "normal 1Gv$\<F3>o\<F3>"
   call assert_equal([[0, 1, 1, 0], [0, 1, 1, 0]], g:VisualStartPos)
   vunmap <F3>
 
+  " Test for getting the position in insert mode with the cursor after the
+  " last character in a line
+  inoremap <expr> <F3> SaveInsertCurrentCharPos()
+  let g:InsertCurrentPos = []
+  exe "normal 1GA\<F3>"
+  exe "normal 2GA\<F3>"
+  exe "normal 3GA\<F3>"
+  exe "normal 4GA\<F3>"
+  exe "normal 2G6li\<F3>"
+  call assert_equal([[0, 1, 1, 0], [0, 2, 10, 0], [0, 3, 2, 0], [0, 4, 10, 0],
+                        \ [0, 2, 7, 0]], g:InsertCurrentPos)
+  iunmap <F3>
+
   %bw!
 endfunc
 
@@ -192,6 +212,10 @@ func Test_setcharpos()
   call setcharpos("'m", [0, 2, 9, 0])
   normal `m
   call assert_equal([2, 11], [line('.'), col('.')])
+  " unload the buffer and try to set the mark
+  let bnr = bufnr()
+  enew!
+  call assert_equal(-1, setcharpos("'m", [bnr, 2, 2, 0]))
 
   %bw!
   call assert_equal(-1, setcharpos('.', [10, 3, 1, 0]))
@@ -202,6 +226,11 @@ func SaveVisualStartCharCol()
   return ''
 endfunc
 
+func SaveInsertCurrentCharCol()
+  call add(g:InsertCurrentCol, charcol('.'))
+  return ''
+endfunc
+
 " Test for the charcol() function
 func Test_charcol()
   call assert_fails('call charcol({})', 'E731:')
@@ -239,19 +268,36 @@ func Test_charcol()
   vnoremap <expr> <F3> SaveVisualStartCharCol()
   let g:VisualStartCol = []
   exe "normal 2G6lv$\<F3>ohh\<F3>o\<F3>"
-  call assert_equal([7, 9, 5], g:VisualStartCol)
+  call assert_equal([7, 10, 5], g:VisualStartCol)
   call assert_equal(9, charcol('v'))
   let g:VisualStartCol = []
   exe "normal 3Gv$\<F3>o\<F3>"
-  call assert_equal([1, 1], g:VisualStartCol)
+  call assert_equal([1, 2], g:VisualStartCol)
   let g:VisualStartCol = []
   exe "normal 1Gv$\<F3>o\<F3>"
   call assert_equal([1, 1], g:VisualStartCol)
   vunmap <F3>
 
+  " Test for getting the column number in insert mode with the cursor after
+  " the last character in a line
+  inoremap <expr> <F3> SaveInsertCurrentCharCol()
+  let g:InsertCurrentCol = []
+  exe "normal 1GA\<F3>"
+  exe "normal 2GA\<F3>"
+  exe "normal 3GA\<F3>"
+  exe "normal 4GA\<F3>"
+  exe "normal 2G6li\<F3>"
+  call assert_equal([1, 10, 2, 10, 7], g:InsertCurrentCol)
+  iunmap <F3>
+
   %bw!
 endfunc
 
+func SaveInsertCursorCharPos()
+  call add(g:InsertCursorPos, getcursorcharpos('.'))
+  return ''
+endfunc
+
 " Test for getcursorcharpos()
 func Test_getcursorcharpos()
   call assert_equal(getcursorcharpos(), getcursorcharpos(0))
@@ -269,6 +315,19 @@ func Test_getcursorcharpos()
   normal 4G9l
   call assert_equal([0, 4, 9, 0, 9], getcursorcharpos())
 
+  " Test for getting the cursor position in insert mode with the cursor after
+  " the last character in a line
+  inoremap <expr> <F3> SaveInsertCursorCharPos()
+  let g:InsertCursorPos = []
+  exe "normal 1GA\<F3>"
+  exe "normal 2GA\<F3>"
+  exe "normal 3GA\<F3>"
+  exe "normal 4GA\<F3>"
+  exe "normal 2G6li\<F3>"
+  call assert_equal([[0, 1, 1, 0, 1], [0, 2, 10, 0, 15], [0, 3, 2, 0, 2],
+                    \ [0, 4, 10, 0, 10], [0, 2, 7, 0, 12]], g:InsertCursorPos)
+  iunmap <F3>
+
   let winid = win_getid()
   normal 2G5l
   wincmd w