neovim/runtime/lua/vim/text.lua
Gregory Anders 33464189bc
fix(vim.text): handle very long strings (#30075)
Lua's string.byte has a maximum (undocumented) allowable length, so
vim.text.hencode fails on large strings with the error "string slice too
long".

Instead of converting the string to an array of bytes up front, convert
each character to a byte one at a time.
2024-08-17 22:28:03 -05:00

36 lines
802 B
Lua

-- Text processing functions.
local M = {}
--- Hex encode a string.
---
--- @param str string String to encode
--- @return string : Hex encoded string
function M.hexencode(str)
local enc = {} ---@type string[]
for i = 1, #str do
enc[i] = string.format('%02X', str:byte(i, i + 1))
end
return table.concat(enc)
end
--- Hex decode a string.
---
--- @param enc string String to decode
--- @return string? : Decoded string
--- @return string? : Error message, if any
function M.hexdecode(enc)
if #enc % 2 ~= 0 then
return nil, 'string must have an even number of hex characters'
end
local str = {} ---@type string[]
for i = 1, #enc, 2 do
local n = assert(tonumber(enc:sub(i, i + 1), 16))
str[#str + 1] = string.char(n)
end
return table.concat(str), nil
end
return M