Support maxwidth on format

Author: kddnewton

CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) a
 
 ## [Unreleased]
 
+### Added
+
+- Support an optional `maxwidth` second argument to `SyntaxTree.format`.
+
 ### Changed
 
 - Correct the pattern for checking if a dynamic symbol can be converted into a label as a hash key.

lib/syntax_tree.rb

@@ -40,8 +40,8 @@ def self.parse(source)
   end
 
   # Parses the given source and returns the formatted source.
-  def self.format(source)
-    formatter = Formatter.new(source, [])
+  def self.format(source, maxwidth = 80)
+    formatter = Formatter.new(source, [], maxwidth)
     parse(source).format(formatter)
 
     formatter.flush

test/syntax_tree_test.rb

@@ -29,6 +29,10 @@ def test_parse_error
       assert_raises(Parser::ParseError) { SyntaxTree.parse("<>") }
     end
 
+    def test_maxwidth_format
+      assert_equal("foo +\n  bar\n", SyntaxTree.format("foo + bar", 5))
+    end
+
     def test_read
       source = SyntaxTree.read(__FILE__)
       assert_equal(Encoding.default_external, source.encoding)