Prettier

src/lexer.ts

     while (this.position < this.source.length) {
       const result = this.getToken();
       if (!(result instanceof Token)) return result;
-      if (result.type !== TokenTypes.WHITESPACE && result.type !== TokenTypes.COMMENT) {
+      if (
+        result.type !== TokenTypes.WHITESPACE &&
+        result.type !== TokenTypes.COMMENT
+      ) {
         this.tokens.push(result);
       }
 

src/parser.ts

     const rules: AST.Rule[] = [];
     const children: AST.RuleSet[] = [];
 
-    while ([TokenTypes.PROPERTY, TokenTypes.LPAREN].includes(this.currentToken().type)) {
+    while (
+      [TokenTypes.PROPERTY, TokenTypes.LPAREN].includes(
+        this.currentToken().type
+      )
+    ) {
       if (this.currentToken().type === TokenTypes.PROPERTY) {
         const propertyToken = this.eat(TokenTypes.PROPERTY);
         if (propertyToken instanceof ParserError) return propertyToken;
         if (this.nextToken().type === TokenTypes.FUNCTION_NAME)
           return this.application();
       default:
-        return this.error(
-          `Unexpected ${type}`,
-          this.currentToken()
-        );
+        return this.error(`Unexpected ${type}`, this.currentToken());
     }
   }
 

src/tests/parser.test.ts

 
 test('parses mixin', (t) => {
   t.plan(2);
-  const result = parse('(@mixin centered ($width) :max-width $width :margin auto)');
+  const result = parse(
+    '(@mixin centered ($width) :max-width $width :margin auto)'
+  );
   t.false(result instanceof ParserError);
   if (!(result instanceof LexerError) && !(result instanceof ParserError)) {
     t.deepEqual(result.tree, [
       new AST.Mixin(
         literalToken('centered'),
-        [
-          identifierNode('width'),
-        ],
+        [identifierNode('width')],
         [
           new AST.Rule(
             new AST.Property(propertyToken('max-width')),
-            identifierNode('width'),
+            identifierNode('width')
           ),
           new AST.Rule(
             new AST.Property(propertyToken('margin')),