feat: half-open range patterns

Author: amaanq

grammar.js

@@ -1388,10 +1388,15 @@ module.exports = grammar({
         $._literal_pattern,
         $._path,
       ),
-      choice('...', '..='),
       choice(
-        $._literal_pattern,
-        $._path,
+        seq(
+          choice('...', '..='),
+          choice(
+            $._literal_pattern,
+            $._path,
+          ),
+        ),
+        '..',
       ),
     ),
 

test/corpus/patterns.txt

@@ -162,6 +162,7 @@ match x {
   Some(1 ... 5) => a,
   a @ b...c => a,
   a @ b..=c => a,
+  d.. => a,
 }
 
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@@ -215,6 +216,11 @@ match x {
               (range_pattern
                 (identifier)
                 (identifier))))
+          value: (identifier))
+        (match_arm
+          pattern: (match_pattern
+            (range_pattern
+              (identifier)))
           value: (identifier))))))
 
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