Add support for indexing builtin libraries

src/lexer/init.lua

@@ -50,6 +50,7 @@ local COMMENT_INCOMP = "%-%-.*" --Incompleted Singleline-Comment
 local lang = require(script.language)
 local lua_keyword = lang.keyword
 local lua_builtin = lang.builtin
+local lua_libraries = lang.libraries
 
 local lua_matches = {
 	-- Indentifiers
@@ -94,8 +95,8 @@ function lexer.scan(s: string)
 
 	local index = 1
 	local sz = #s
+	local p1, p2 = "", ""
 
-	-- stylua: ignore
 	return function()
 		if index <= sz then
 			for _, m in ipairs(lua_matches) do
@@ -109,21 +110,42 @@ function lexer.scan(s: string)
 					--end
 
 					local t = m[2]
+					local t2 = t
+
+					-- Process t into t2
 					if t == "var" then
 						-- Since we merge spaces into the tok, we need to remove them
 						-- in order to check the actual word it contains
 						local cleanTok = string.gsub(tok, Cleaner, "")
 
 						if lua_keyword[cleanTok] then
-							return "keyword", tok
+							t2 = "keyword"
 						elseif lua_builtin[cleanTok] then
-							return "builtin", tok
+							t2 = "builtin"
 						else
-							return "iden", tok
+							t2 = "iden"
+						end
+
+						if string.find(p1, "%.[%s%c]*$") then
+							-- The previous was a . so we need to special case indexing things
+							local parent = string.gsub(p2, Cleaner, "")
+							local lib = lua_libraries[parent]
+							if lib and lib[cleanTok] then
+								-- Indexing a builtin lib with existing item, treat as a builtin
+								t2 = "builtin"
+							else
+								-- Indexing a non builtin, can't be treated as a keyword/builtin
+								t2 = "iden"
+							end
+							-- print("indexing",parent,"with",cleanTok,"as",t2)
 						end
-					else
-						return t, tok
 					end
+
+					-- Record last 2 tokens for the indexing context check
+					p2 = p1
+					p1 = tok
+
+					return t2, tok
 				end
 			end
 		end

src/lexer/language.lua

@@ -121,4 +121,132 @@ return {
 		["Vector3"] = true,
 		["Vector3int16"] = true,
 	},
+
+	libraries = {
+		math = {
+			abs = true,
+			acos = true,
+			asin = true,
+			atan = true,
+			atan2 = true,
+			ceil = true,
+			clamp = true,
+			cos = true,
+			cosh = true,
+			deg = true,
+			exp = true,
+			floor = true,
+			fmod = true,
+			frexp = true,
+			ldexp = true,
+			log = true,
+			log10 = true,
+			max = true,
+			min = true,
+			modf = true,
+			noise = true,
+			pow = true,
+			rad = true,
+			random = true,
+			sinh = true,
+			sqrt = true,
+			tan = true,
+			tanh = true,
+			sign = true,
+			sin = true,
+			randomseed = true,
+
+			huge = true,
+			pi = true,
+		},
+
+		string = {
+			byte = true,
+			char = true,
+			find = true,
+			format = true,
+			gmatch = true,
+			gsub = true,
+			len = true,
+			lower = true,
+			match = true,
+			rep = true,
+			reverse = true,
+			split = true,
+			sub = true,
+			upper = true,
+		},
+
+		table = {
+			concat = true,
+			foreach = true,
+			foreachi = true,
+			getn = true,
+			insert = true,
+			remove = true,
+			sort = true,
+			find = true,
+			pack = true,
+			unpack = true,
+			move = true,
+			create = true,
+		},
+
+		debug = {
+			profilebegin = true,
+			profileend = true,
+			traceback = true,
+		},
+
+		task = {
+			wait = true,
+			spawn = true,
+			delay = true,
+			defer = true,
+		},
+
+		os = {
+			time = true,
+			date = true,
+			difftime = true,
+			clock = true,
+		},
+
+		coroutine = {
+			create = true,
+			isyieldable = true,
+			resume = true,
+			running = true,
+			status = true,
+			wrap = true,
+			yield = true,
+		},
+
+		bit32 = {
+			arshift = true,
+			band = true,
+			bnot = true,
+			bor = true,
+			btest = true,
+			bxor = true,
+			extract = true,
+			lrotate = true,
+			lshift = true,
+			replace = true,
+			rrotate = true,
+			rshift = true,
+		},
+
+		utf8 = {
+			char = true,
+			codepoint = true,
+			codes = true,
+			graphemes = true,
+			len = true,
+			nfcnormalize = true,
+			nfdnormalize = true,
+			offset = true,
+			charpattern = true,
+		},
+	},
 }