path: root/runtime/lua/vim/lsp/util.lua

local protocol = require 'vim.lsp.protocol'
local vim = vim
local validate = vim.validate
local api = vim.api
local list_extend = vim.list_extend

local M = {}

--- Diagnostics received from the server via `textDocument/publishDiagnostics`
-- by buffer.
--
--  {<bufnr>: {diagnostics}}
--
-- This contains only entries for active buffers. Entries for detached buffers
-- are discarded.
--
-- If you override the `textDocument/publishDiagnostic` callback,
-- this will be empty unless you call `buf_diagnostics_save_positions`.
--
--
-- Diagnostic is:
--
-- {
--    range: Range
--    message: string
--    severity?: DiagnosticSeverity
--    code?: number | string
--    source?: string
--    tags?: DiagnosticTag[]
--    relatedInformation?: DiagnosticRelatedInformation[]
-- }
M.diagnostics_by_buf = {}

local split = vim.split
local function split_lines(value)
  return split(value, '\n', true)
end

local function ok_or_nil(status, ...)
  if not status then return end
  return ...
end
local function npcall(fn, ...)
  return ok_or_nil(pcall(fn, ...))
end

function M.set_lines(lines, A, B, new_lines)
  -- 0-indexing to 1-indexing
  local i_0 = A[1] + 1
  -- If it extends past the end, truncate it to the end. This is because the
  -- way the LSP describes the range including the last newline is by
  -- specifying a line number after what we would call the last line.
  local i_n = math.min(B[1] + 1, #lines)
  if not (i_0 >= 1 and i_0 <= #lines and i_n >= 1 and i_n <= #lines) then
    error("Invalid range: "..vim.inspect{A = A; B = B; #lines, new_lines})
  end
  local prefix = ""
  local suffix = lines[i_n]:sub(B[2]+1)
  if A[2] > 0 then
    prefix = lines[i_0]:sub(1, A[2])
  end
  local n = i_n - i_0 + 1
  if n ~= #new_lines then
    for _ = 1, n - #new_lines do table.remove(lines, i_0) end
    for _ = 1, #new_lines - n do table.insert(lines, i_0, '') end
  end
  for i = 1, #new_lines do
    lines[i - 1 + i_0] = new_lines[i]
  end
  if #suffix > 0 then
    local i = i_0 + #new_lines - 1
    lines[i] = lines[i]..suffix
  end
  if #prefix > 0 then
    lines[i_0] = prefix..lines[i_0]
  end
  return lines
end

local function sort_by_key(fn)
  return function(a,b)
    local ka, kb = fn(a), fn(b)
    assert(#ka == #kb)
    for i = 1, #ka do
      if ka[i] ~= kb[i] then
        return ka[i] < kb[i]
      end
    end
    -- every value must have been equal here, which means it's not less than.
    return false
  end
end
local edit_sort_key = sort_by_key(function(e)
  return {e.A[1], e.A[2], e.i}
end)

local function get_line_byte_from_line_character(bufnr, lnum, cnum)
  -- Skip check when the byte and character position is the same
  if cnum > 0 then
    local lines = api.nvim_buf_get_lines(bufnr, lnum, lnum+1, false)

    if #lines > 0 then
      return vim.str_byteindex(lines[1], cnum)
    end
  end

  return cnum
end

function M.apply_text_edits(text_edits, bufnr)
  if not next(text_edits) then return end
  if not api.nvim_buf_is_loaded(bufnr) then
    vim.fn.bufload(bufnr)
  end
  local start_line, finish_line = math.huge, -1
  local cleaned = {}
  for i, e in ipairs(text_edits) do
    -- adjust start and end column for UTF-16 encoding of non-ASCII characters
    local start_row = e.range.start.line
    local start_col = get_line_byte_from_line_character(
      bufnr,
      start_row,
      e.range.start.character)
    local end_row = e.range["end"].line
    local end_col = get_line_byte_from_line_character(
      bufnr,
      end_row,
      e.range["end"].character)
    start_line = math.min(e.range.start.line, start_line)
    finish_line = math.max(e.range["end"].line, finish_line)
    -- TODO(ashkan) sanity check ranges for overlap.
    table.insert(cleaned, {
      i = i;
      A = {start_row; start_col};
      B = {end_row; end_col};
      lines = vim.split(e.newText, '\n', true);
    })
  end

  -- Reverse sort the orders so we can apply them without interfering with
  -- eachother. Also add i as a sort key to mimic a stable sort.
  table.sort(cleaned, edit_sort_key)
  local lines = api.nvim_buf_get_lines(bufnr, start_line, finish_line + 1, false)
  local fix_eol = api.nvim_buf_get_option(bufnr, 'fixeol')
  local set_eol = fix_eol and api.nvim_buf_line_count(bufnr) <= finish_line + 1
  if set_eol and #lines[#lines] ~= 0 then
    table.insert(lines, '')
  end

  for i = #cleaned, 1, -1 do
    local e = cleaned[i]
    local A = {e.A[1] - start_line, e.A[2]}
    local B