numeric.c: wrong type step should raise TypeError

* numeric.c (num_step_scan_args): comparison String with Numeric
  should raise TypeError. it is an invalid type, but not a
  mismatch the number of arguments.  [ruby-core:62430] [Bug #9810]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53949 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Fri Feb 26 14:40:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* numeric.c (num_step_scan_args): comparison String with Numeric
+	  should raise TypeError. it is an invalid type, but not a
+	  mismatch the number of arguments.  [ruby-core:62430] [Bug #9810]
+
 Fri Feb 26 14:39:39 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* doc/extension.rdoc, doc/extension.ja.rdoc: add editor local

numeric.c

@@ -2081,6 +2081,34 @@ ruby_num_interval_step_size(VALUE from, VALUE to, VALUE step, int excl)
     }
 }
 
+static VALUE
+num_step_compare_with_zero(VALUE num)
+{
+    VALUE zero = INT2FIX(0);
+    return rb_check_funcall(num, '>', 1, &zero);
+}
+
+static int
+num_step_negative_p(VALUE num)
+{
+    const ID mid = '<';
+    VALUE r;
+
+    if (FIXNUM_P(num)) {
+	if (method_basic_p(rb_cFixnum))
+	    return (SIGNED_VALUE)num < 0;
+    }
+    else if (RB_TYPE_P(num, T_BIGNUM)) {
+	if (method_basic_p(rb_cBignum))
+	    return BIGNUM_NEGATIVE_P(num);
+    }
+    r = rb_rescue(num_step_compare_with_zero, num, coerce_rescue_quiet, Qnil);
+    if (r == Qundef) {
+	coerce_failed(num, INT2FIX(0));
+    }
+    return !RTEST(r);
+}
+
 static int
 num_step_scan_args(int argc, const VALUE *argv, VALUE *to, VALUE *step)
 {
@@ -2115,7 +2143,7 @@ num_step_scan_args(int argc, const VALUE *argv, VALUE *to, VALUE *step)
     if (NIL_P(*step)) {
 	*step = INT2FIX(1);
     }
-    desc = !positive_int_p(*step);
+    desc = num_step_negative_p(*step);
     if (NIL_P(*to)) {
 	*to = desc ? DBL2NUM(-INFINITY) : DBL2NUM(INFINITY);
     }

test/ruby/test_float.rb

@@ -601,7 +601,7 @@ class TestFloat < Test::Unit::TestCase
   end
 
   def test_num2dbl
-    assert_raise(ArgumentError) do
+    assert_raise(TypeError) do
       1.0.step(2.0, "0.5") {}
     end
     assert_raise(TypeError) do

test/ruby/test_numeric.rb

@@ -262,8 +262,8 @@ class TestNumeric < Test::Unit::TestCase
     assert_raise(ArgumentError) { 1.step(10, 1, 0).size }
     assert_raise(ArgumentError) { 1.step(10, 0) { } }
     assert_raise(ArgumentError) { 1.step(10, 0).size }
-    assert_raise(ArgumentError) { 1.step(10, "1") { } }
-    assert_raise(ArgumentError) { 1.step(10, "1").size }
+    assert_raise(TypeError) { 1.step(10, "1") { } }
+    assert_raise(TypeError) { 1.step(10, "1").size }
     assert_raise(TypeError) { 1.step(10, nil) { } }
     assert_raise(TypeError) { 1.step(10, nil).size }
     assert_nothing_raised { 1.step(by: 0, to: nil) }