Parse error with goto as variable name for non-Lua5.2

[JohnnyMorganz]

In non-Lua5.2 code, using goto as a variable name leads to a parsing error.
It seems to be stemming from

full-moon/full-moon/src/tokenizer.rs

Lines 33 to 34 in 633774a

	// TODO: This only is valid in Lua 5.2
	Goto => "goto",

where goto is a restricted symbol (for Lua 5.2+), but this is leaking into the parsing for 5.1/Luau.

Reported in JohnnyMorganz/StyLua#229

[Kampfkarren]

Out of curiosity, does local goto = 1 work in Lua 5.2 for backwards compatibility? If not this becomes a real pain considering we only support Lua 5.2 as a feature, and not as a toggleable.

[JohnnyMorganz]

Tested it using https://www.lua.org/cgi-bin/demo since I don't have a Lua 5.2 installation to hand, and local goto = 1 is not allowed. It is also mentioned as a reserved keyword https://www.lua.org/manual/5.2/manual.html#3.1.

I guess this can probably be fixed, but we are breaking the additive nature of rust features - doesn't look like there's any great solution here, other than waiting for pluggable parsing

[Kampfkarren]

God that is annoying.