Fix parsing of broken syntax [x

Author: c42f

src/parser.jl

@@ -2781,9 +2781,10 @@ function parse_cat(ps::ParseState, closer, end_is_symbol)
     end
     parse_eq_star(ps)
     k = peek(ps, skip_newlines=true)
-    if k == K"," || k == closer
+    if k == K"," || (is_closing_token(ps, k) && k != K";")
         if k == K","
             # [x,]  ==>  (vect x)
+            # [x    ==>  (vect x)
             bump(ps, TRIVIA_FLAG)
         end
         # [x]      ==>  (vect x)

test/parser.jl

@@ -581,6 +581,7 @@ tests = [
         "[]"        =>  "(vect)"
         "[x,]"      =>  "(vect x)"
         "[x]"       =>  "(vect x)"
+        "[x"        =>  "(vect x (error-t))"
         "[x \n ]"   =>  "(vect x)"
         "[x \n\n ]" =>  "(vect x)"
         "[x for a in as]"  =>  "(comprehension (generator x (= a as)))"