yuckHEADmaster

1 files changed, 17 insertions, 6 deletions

diff --git a/init.lua b/init.lua
index 1c8cda7..27cf638 100644
--- a/init.lua
+++ b/init.lua
@@ -115,12 +115,22 @@ local function match_at(str, pattern, pos)
 	if t then return t[1] - 1, t[#t] - 1 end
 end
 
+--- Returns a unique grammar rule name for the given lexer's rule name.
+local function rule_id(lexer, name) return lexer._name .. '.' .. name end
+
+-- get_rule that doesn't assert on me:
+local function get_rule(lexer, id)
+  if lexer._lexer then lexer = lexer._lexer end -- proxy; get true parent
+  if id == 'whitespace' then return l.V(rule_id(lexer, id)) end -- special case
+  return (lexer._RULES or lexer._rules)[id]
+end
+
 local function escaping_context(lexer, range, data)
-	local rules = lexer._RULES
 	local p
 	for _, name in ipairs({vis.lexers.COMMENT, vis.lexers.STRING}) do
-		if rules[name] then
-			p = p and p + rules[name] / 0 or rules[name] / 0
+		local rule = get_rule(lexer, name)
+		if rule then
+			p = p and p + rule / 0 or rule / 0
 		end
 	end
 	if not p then return {} end
@@ -131,10 +141,11 @@ local function escaping_context(lexer, range, data)
 	local escaped_range = {e1 + 1, e2}
 	local escaped_data = data:sub(e1 + 1, e2)
 	for _, level in ipairs({vis.lexers.COMMENT, vis.lexers.STRING}) do
-		if l.match(rules[level] / 0 * -1, escaped_data) then
+		if l.match(get_rule(lexer, level) / 0 * -1, escaped_data) then
 			for _, name in ipairs(precedence[level]) do
-				if rules[name] then
-					p = p and p + rules[name] / 0 or rules[name] / 0
+				local rule = get_rule(lexer, name)
+				if rule then
+					p = p and p + rule / 0 or rule / 0
 				end
 			end
 			return {escape = p, range = escaped_range}