feat: add and apply eslint formatting

.eslintrc.js

@@ -0,0 +1,20 @@
+module.exports = {
+  'env': {
+    'commonjs': true,
+    'es2021': true,
+  },
+  'extends': 'google',
+  'overrides': [
+  ],
+  'parserOptions': {
+    'ecmaVersion': 'latest',
+    'sourceType': 'module',
+  },
+  'rules': {
+    'indent': ['error', 2, {'SwitchCase': 1}],
+    'max-len': [
+      'error',
+      {'code': 120, 'ignoreComments': true, 'ignoreUrls': true, 'ignoreStrings': true},
+    ],
+  },
+};

grammar.js

@@ -1,3 +1,15 @@
+/**
+ * @file JSON grammar for tree-sitter
+ * @author Max Brunsfeld
+ * @license MIT
+ */
+
+/* eslint-disable arrow-parens */
+/* eslint-disable camelcase */
+/* eslint-disable-next-line spaced-comment */
+/// <reference types="tree-sitter-cli/dsl" />
+// @ts-check
+
 module.exports = grammar({
   name: 'json',
 
@@ -7,7 +19,7 @@ module.exports = grammar({
   ],
 
   supertypes: $ => [
-    $._value
+    $._value,
   ],
 
   rules: {
@@ -20,80 +32,96 @@ module.exports = grammar({
       $.string,
       $.true,
       $.false,
-      $.null
+      $.null,
     ),
 
     object: $ => seq(
-      "{", commaSep($.pair), "}"
+      '{', commaSep($.pair), '}',
     ),
 
     pair: $ => seq(
-      field("key", choice($.string, $.number)),
-      ":",
-      field("value", $._value)
+      field('key', choice($.string, $.number)),
+      ':',
+      field('value', $._value),
     ),
 
     array: $ => seq(
-      "[", commaSep($._value), "]"
+      '[', commaSep($._value), ']',
     ),
 
     string: $ => choice(
       seq('"', '"'),
-      seq('"', $.string_content, '"')
+      seq('"', $.string_content, '"'),
     ),
 
     string_content: $ => repeat1(choice(
       token.immediate(prec(1, /[^\\"\n]+/)),
-      $.escape_sequence
+      $.escape_sequence,
     )),
 
     escape_sequence: _ => token.immediate(seq(
       '\\',
-      /(\"|\\|\/|b|f|n|r|t|u)/
+      /(\"|\\|\/|b|f|n|r|t|u)/,
     )),
 
     number: _ => {
-      const decimal_digits = /\d+/
-      const signed_integer = seq(optional('-'), decimal_digits)
-      const exponent_part = seq(choice('e', 'E'), signed_integer)
+      const decimal_digits = /\d+/;
+      const signed_integer = seq(optional('-'), decimal_digits);
+      const exponent_part = seq(choice('e', 'E'), signed_integer);
 
       const decimal_integer_literal = seq(
         optional('-'),
         choice(
           '0',
-          seq(/[1-9]/, optional(decimal_digits))
-        )
-      )
+          seq(/[1-9]/, optional(decimal_digits)),
+        ),
+      );
 
       const decimal_literal = choice(
         seq(decimal_integer_literal, '.', optional(decimal_digits), optional(exponent_part)),
-        seq(decimal_integer_literal, optional(exponent_part))
-      )
+        seq(decimal_integer_literal, optional(exponent_part)),
+      );
 
-      return token(decimal_literal)
+      return token(decimal_literal);
     },
 
-    true: _ => "true",
+    true: _ => 'true',
 
-    false: _ => "false",
+    false: _ => 'false',
 
-    null: _ => "null",
+    null: _ => 'null',
 
     comment: _ => token(choice(
       seq('//', /.*/),
       seq(
         '/*',
         /[^*]*\*+([^/*][^*]*\*+)*/,
-        '/'
-      )
+        '/',
+      ),
     )),
-  }
+  },
 });
 
+/**
+ * Creates a rule to match one or more of the rules separated by a comma
+ *
+ * @param {RuleOrLiteral} rule
+ *
+ * @return {SeqRule}
+ *
+ */
 function commaSep1(rule) {
-  return seq(rule, repeat(seq(",", rule)))
+  return seq(rule, repeat(seq(',', rule)));
 }
 
+/**
+ * Creates a rule to optionally match one or more of the rules separated by a comma
+ *
+ * @param {RuleOrLiteral} rule
+ *
+ * @return {ChoiceRule}
+ *
+ */
 function commaSep(rule) {
-  return optional(commaSep1(rule))
+  return optional(commaSep1(rule));
 }

package.json

@@ -13,6 +13,8 @@
     "nan": "^2.14.1"
   },
   "devDependencies": {
+    "eslint": ">=5.16.0",
+    "eslint-config-google": "^0.14.0",
     "tree-sitter-cli": "^0.20.8"
   },
   "scripts": {