| local M = {} | |
| --- Query the host terminal emulator for terminfo capabilities. | |
| --- | |
| --- This function sends the XTGETTCAP DCS sequence to the host terminal emulator asking the terminal | |
| --- to send us its terminal capabilities. These are strings that are normally taken from a terminfo | |
| --- file, however an up to date terminfo database is not always available (particularly on remote | |
| --- machines), and many terminals continue to misidentify themselves or do not provide their own | |
| --- terminfo file, making the terminfo database unreliable. | |
| --- | |
| --- Querying the terminal guarantees that we get a truthful answer, but only if the host terminal | |
| --- emulator supports the XTGETTCAP sequence. | |
| --- | |
| --- @param caps string|table A terminal capability or list of capabilities to query | |
| --- @param cb fun(cap:string, found:boolean, seq:string?) Callback function which is called for | |
| --- each capability in {caps}. {found} is set to true if the capability was found or false | |
| --- otherwise. {seq} is the control sequence for the capability if found, or nil for | |
| --- boolean capabilities. | |
| function M.query(caps, cb) | |
| vim.validate('caps', caps, { 'string', 'table' }) | |
| vim.validate('cb', cb, 'function') | |
| if type(caps) ~= 'table' then | |
| caps = { caps } | |
| end | |
| local pending = {} ---@type table<string, boolean> | |
| for _, v in ipairs(caps) do | |
| pending[v] = true | |
| end | |
| local timer = assert(vim.uv.new_timer()) | |
| local id = vim.api.nvim_create_autocmd('TermResponse', { | |
| nested = true, | |
| callback = function(args) | |
| local resp = args.data.sequence ---@type string | |
| local k, rest = resp:match('^\027P1%+r(%x+)(.*)$') | |
| if k and rest then | |
| local cap = vim.text.hexdecode(k) | |
| if not cap or not pending[cap] then | |
| -- Received a response for a capability we didn't request. This can happen if there are | |
| -- multiple concurrent XTGETTCAP requests | |
| return | |
| end | |
| local seq ---@type string? | |
| if rest:match('^=%x+$') then | |
| seq = vim.text | |
| .hexdecode(rest:sub(2)) | |
| :gsub('\\E', '\027') | |
| :gsub('%%p%d', '') | |
| :gsub('\\(%d+)', string.char) | |
| end | |
| cb(cap, true, seq) | |
| pending[cap] = nil | |
| if next(pending) == nil then | |
| return true | |
| end | |
| end | |
| end, | |
| }) | |
| local encoded = {} ---@type string[] | |
| for i = 1, #caps do | |
| encoded[i] = vim.text.hexencode(caps[i]) | |
| end | |
| local query = string.format('\027P+q%s\027\\', table.concat(encoded, ';')) | |
| io.stdout:write(query) | |
| timer:start(1000, 0, function() | |
| -- Delete the autocommand if no response was received | |
| vim.schedule(function() | |
| -- Suppress error if autocommand has already been deleted | |
| pcall(vim.api.nvim_del_autocmd, id) | |
| -- Call the callback for all capabilities that were not found | |
| for k in pairs(pending) do | |
| cb(k, false, nil) | |
| end | |
| end) | |
| if not timer:is_closing() then | |
| timer:close() | |
| end | |
| end) | |
| end | |
| return M | |