fix: allow or patterns to begin with a |

Author: amaanq

grammar.js

@@ -1208,7 +1208,7 @@ module.exports = grammar({
     ),
 
     match_pattern: $ => seq(
-      choice($._pattern, alias($.closure_expression, $.closure_pattern)),
+      $._pattern,
       optional(seq('if', field('condition', $._condition))),
     ),
 
@@ -1422,10 +1422,9 @@ module.exports = grammar({
       $._pattern,
     ),
 
-    or_pattern: $ => prec.left(-2, seq(
-      $._pattern,
-      '|',
-      $._pattern,
+    or_pattern: $ => prec.left(-2, choice(
+      seq($._pattern, '|', $._pattern),
+      seq('|', $._pattern),
     )),
 
     // Section - Literals

test/corpus/patterns.txt

@@ -165,6 +165,13 @@ match x {
   d.. => a,
 }
 
+match name {
+  | "IPV6_FLOWINFO"
+  | "IPV6_FLOWLABEL_MGR"
+  | "IPV6_FLOWINFO_SEND" => true,
+  _ => false,
+}
+
 --------------------------------------------------------------------------------
 
 (source_file
@@ -221,7 +228,26 @@ match x {
           pattern: (match_pattern
             (range_pattern
               (identifier)))
-          value: (identifier))))))
+          value: (identifier)))))
+  (expression_statement
+    (match_expression
+      value: (identifier)
+      body: (match_block
+        (match_arm
+          pattern: (match_pattern
+            (or_pattern
+              (or_pattern
+                (or_pattern
+                  (string_literal
+                    (string_content)))
+                (string_literal
+                  (string_content)))
+              (string_literal
+                (string_content))))
+          value: (boolean_literal))
+        (match_arm
+          pattern: (match_pattern)
+          value: (boolean_literal))))))
 
 ================================================================================
 Or patterns
@@ -251,12 +277,6 @@ fn foo((1 | 2 | 3): u8) {}
 
 if let x!() | y!() = () {}
 
-// Discomment after box pattern land on master
-// let box (A | B | C);
-
-// Not handled cause devs didn't got into agreement if should be acceptd or not
-// |Ok(x) | Err(x)| expr();
-
 --------------------------------------------------------------------------------
 
 (source_file
@@ -387,11 +407,7 @@ if let x!() | y!() = () {}
             macro: (identifier)
             (token_tree)))
         value: (unit_expression))
-      consequence: (block)))
-  (line_comment)
-  (line_comment)
-  (line_comment)
-  (line_comment))
+      consequence: (block))))
 
 ================================================================================
 Inline const or Const blocks as pattern