fix: allow "not in" & "is not" to be queried

Author: ObserverOfTime

grammar.js

@@ -806,6 +806,10 @@ module.exports = grammar({
       field('argument', $.primary_expression),
     )),
 
+    _not_in: _ => seq('not', 'in'),
+
+    _is_not: _ => seq('is', 'not'),
+
     comparison_operator: $ => prec.left(PREC.compare, seq(
       $.primary_expression,
       repeat1(seq(
@@ -819,9 +823,9 @@ module.exports = grammar({
             '>',
             '<>',
             'in',
-            alias(seq('not', 'in'), 'not in'),
+            alias($._not_in, 'not in'),
             'is',
-            alias(seq('is', 'not'), 'is not'),
+            alias($._is_not, 'is not'),
           )),
         $.primary_expression,
       )),

queries/highlights.scm

@@ -96,6 +96,8 @@
   "is"
   "not"
   "or"
+  "is not"
+  "not in"
 ] @operator
 
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