Add tests for #4746

test/t/syntax.rb

@@ -451,6 +451,18 @@ assert('optional block argument in the rhs default expressions') do
   assert_nil(Proc.new {|foo = foo| foo}.call)
 end
 
+assert('local variable definition in default value and subsequent arguments') do
+  def m(a = b = 1, c) [a, b, c] end
+  assert_equal([1, 1, :c], m(:c))
+  assert_equal([:a, nil, :c], m(:a, :c))
+
+  def m(a = b = 1, &c) [a, b, c ? true : nil] end
+  assert_equal([1, 1, nil], m)
+  assert_equal([1, 1, true], m{})
+  assert_equal([:a, nil, nil], m(:a))
+  assert_equal([:a, nil, true], m(:a){})
+end
+
 assert('multiline comments work correctly') do
 =begin
 this is a comment with nothing after begin and end
@@ -654,4 +666,8 @@ assert 'keyword arguments' do
   result = m(1, 2, e: 3, g: 4, h: 5, i: 6, &(l = ->{}))
   assert_equal([1, 1, [], 2, 3, 2, 4, { h: 5, i: 6 }, l], result)
 =end
+
+  def m(a: b = 1, c:) [a, b, c] end
+  assert_equal([1, 1, :c], m(c: :c))
+  assert_equal([:a, nil, :c], m(a: :a, c: :c))
 end