rb_rational_raw: make a denominator always positive

ext/-test-/rational/rat.c

@@ -29,9 +29,17 @@ gcd_gmp(VALUE x, VALUE y)
 #define gcd_gmp rb_f_notimplement
 #endif
 
+static VALUE
+s_rational_raw(VALUE klass, VALUE x, VALUE y)
+{
+    return rb_rational_raw(x, y);
+}
+
 void
 Init_rational(VALUE klass)
 {
     rb_define_method(rb_cInteger, "gcd_normal", gcd_normal, 1);
     rb_define_method(rb_cInteger, "gcd_gmp", gcd_gmp, 1);
+
+    rb_define_singleton_method(rb_cRational, "raw", s_rational_raw, 2);
 }

rational.c

@@ -1927,6 +1927,10 @@ rb_gcdlcm(VALUE self, VALUE other)
 VALUE
 rb_rational_raw(VALUE x, VALUE y)
 {
+    if (INT_NEGATIVE_P(y)) {
+        x = rb_int_uminus(x);
+        y = rb_int_uminus(y);
+    }
     return nurat_s_new_internal(rb_cRational, x, y);
 }
 

test/-ext-/rational/test_rat.rb

@@ -29,4 +29,18 @@ class TestRational < Test::Unit::TestCase
     rescue NotImplementedError
     end
   end
+
+  def test_rb_rational_raw
+    rat = Rational.raw(1, 2)
+    assert_equal(1, rat.numerator)
+    assert_equal(2, rat.denominator)
+
+    rat = Rational.raw(-1, 2)
+    assert_equal(-1, rat.numerator)
+    assert_equal(2, rat.denominator)
+
+    rat = Rational.raw(1, -2)
+    assert_equal(-1, rat.numerator)
+    assert_equal(2, rat.denominator)
+  end
 end