Add boolean-typed select values

grammar.js

@@ -143,6 +143,7 @@ module.exports = grammar({
     select_case: ($) => seq(
       field("pattern", choice(
         $._string_literal,
+        $.boolean_literal,
         alias("default", $.default),
       )),
       ":",

src/grammar.json

@@ -606,6 +606,10 @@
                 "type": "SYMBOL",
                 "name": "_string_literal"
               },
+              {
+                "type": "SYMBOL",
+                "name": "boolean_literal"
+              },
               {
                 "type": "ALIAS",
                 "content": {

src/node-types.json

@@ -353,6 +353,10 @@
         "multiple": false,
         "required": true,
         "types": [
+          {
+            "type": "boolean_literal",
+            "named": true
+          },
           {
             "type": "default",
             "named": true

test/corpus/select.txt

@@ -226,6 +226,33 @@ foo = select(release_variable("ONE", "TWO"), {
           (default)
           (interpreted_string_literal))))))
 
+================================================================================
+Select (boolean typed)
+================================================================================
+
+foo = select(some_boolean("IS_TRUE"), {
+    true: "true",
+    false: "false",
+})
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (assignment
+    (identifier)
+    (operator)
+    (select_expression
+      (select_value
+        (identifier)
+        (interpreted_string_literal))
+      (select_cases
+        (select_case
+          (boolean_literal)
+          (interpreted_string_literal))
+        (select_case
+          (boolean_literal)
+          (interpreted_string_literal))))))
+
 ================================================================================
 Select as an identifier
 ================================================================================