feat: add vim.str_utf_pos function

vim.str_utf_pos returns the codepoints for all utf-8 chars (only, currently)
in a string
This commit is contained in:
Michael Lingelbach 2021-10-22 22:48:46 -07:00
parent cb15055c29
commit d752cbc4d2
2 changed files with 32 additions and 0 deletions

View File

@ -176,6 +176,29 @@ static int nlua_str_utfindex(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
return 2;
}
/// return byte indices of codepoints in a string (only supports utf-8 currently).
///
/// Expects a string.
///
/// Returns a list of codepoints.
static int nlua_str_utf_pos(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
{
size_t s1_len;
const char *s1 = luaL_checklstring(lstate, 1, &s1_len);
lua_newtable(lstate);
size_t idx = 1;
size_t clen;
for (size_t i = 0; i < s1_len && s1[i] != NUL; i += clen) {
clen = (size_t)utf_ptr2len_len((const char_u *)(s1)+i, (int)(s1_len-i));
lua_pushinteger(lstate, (long)i + 1);
lua_rawseti(lstate, -2, (int)idx);
idx++;
}
return 1;
}
/// convert UTF-32 or UTF-16 indices to byte index.
///
/// Expects up to three args: string, index and use_utf16.
@ -435,6 +458,9 @@ static int nlua_state_init(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
// str_byteindex
lua_pushcfunction(lstate, &nlua_str_byteindex);
lua_setfield(lstate, -2, "str_byteindex");
// str_utf_pos
lua_pushcfunction(lstate, &nlua_str_utf_pos);
lua_setfield(lstate, -2, "str_utf_pos");
// neovim version
lua_pushcfunction(lstate, &nlua_nvim_version);
lua_setfield(lstate, -2, "version");

View File

@ -179,6 +179,12 @@ describe('lua stdlib', function()
end
end)
it("vim.str_utf_pos", function()
exec_lua([[_G.test_text = "xy åäö ɧ 汉语 ↥ 🤦x🦄 å بِيَّ"]])
local expected_positions = { 1,2,3,4,6,8,10,11,13,14,17,20,21,24,25,29,30,34,35,36,38,39,41,43,45,47 }
eq(expected_positions, exec_lua("return vim.str_utf_pos(_G.test_text)"))
end)
it("vim.schedule", function()
exec_lua([[
test_table = {}