I broke up with neovim....vim is my best friend now

dot_vim/plugged/vim-lsp/autoload/lsp/utils/position.vim

@@ -0,0 +1,91 @@
+" This function can be error prone if the caller forgets to use +1 to vim line
+" so use lsp#utils#position#lsp_to_vim instead
+" Convert a character-index (0-based) to byte-index (1-based)
+" This function requires a buffer specifier (expr, see :help bufname()),
+" a line number (lnum, 1-based), and a character-index (char, 0-based).
+function! s:to_col(expr, lnum, char) abort
+    let l:lines = getbufline(a:expr, a:lnum)
+    if l:lines == []
+        if type(a:expr) != v:t_string || !filereadable(a:expr)
+            " invalid a:expr
+            return a:char + 1
+        endif
+        " a:expr is a file that is not yet loaded as a buffer
+        let l:lines = readfile(a:expr, '', a:lnum)
+        if l:lines == []
+            " when the file is empty. a:char should be 0 in the case
+            return a:char + 1
+        endif
+    endif
+    let l:linestr = l:lines[-1]
+    return strlen(strcharpart(l:linestr, 0, a:char)) + 1
+endfunction
+
+" The inverse version of `s:to_col`.
+" Convert [lnum, col] to LSP's `Position`.
+function! s:to_char(expr, lnum, col) abort
+    let l:lines = getbufline(a:expr, a:lnum)
+    if l:lines == []
+        if type(a:expr) != v:t_string || !filereadable(a:expr)
+            " invalid a:expr
+            return a:col - 1
+        endif
+        " a:expr is a file that is not yet loaded as a buffer
+        let l:lines = readfile(a:expr, '', a:lnum)
+    endif
+    let l:linestr = l:lines[-1]
+    return strchars(strpart(l:linestr, 0, a:col - 1))
+endfunction
+
+" @param expr = see :help bufname()
+" @param position = {
+"   'line': 1,
+"   'character': 1
+" }
+" @returns [
+"   line,
+"   col
+" ]
+function! lsp#utils#position#lsp_to_vim(expr, position) abort
+    let l:line = lsp#utils#position#lsp_line_to_vim(a:expr, a:position)
+    let l:col = lsp#utils#position#lsp_character_to_vim(a:expr, a:position)
+    return [l:line, l:col]
+endfunction
+
+" @param expr = see :help bufname()
+" @param position = {
+"   'line': 1,
+"   'character': 1
+" }
+" @returns
+"   line
+function! lsp#utils#position#lsp_line_to_vim(expr, position) abort
+    return a:position['line'] + 1
+endfunction
+
+" @param expr = see :help bufname()
+" @param position = {
+"   'line': 1,
+"   'character': 1
+" }
+" @returns
+"   line
+function! lsp#utils#position#lsp_character_to_vim(expr, position) abort
+    let l:line = a:position['line'] + 1 " optimize function overhead by not calling lsp_line_to_vim
+    let l:char = a:position['character']
+    return s:to_col(a:expr, l:line, l:char)
+endfunction
+
+" @param expr = :help bufname()
+" @param pos = [lnum, col]
+" @returns {
+"   'line': line,
+"   'character': character
+" }
+function! lsp#utils#position#vim_to_lsp(expr, pos) abort
+    return {
+         \   'line': a:pos[0] - 1,
+         \   'character': s:to_char(a:expr, a:pos[0], a:pos[1])
+         \ }
+endfunction
+