merge revision(s) 57649,57651: [Backport #13222]

	array.c: finish_exact_sum

	* array.c (finish_exact_sum): extract duplicate code from
	  rb_ary_sum.

	array.c: check if numeric

	* array.c (finish_exact_sum): add 0 and the initial value to check
	  if the latter is numeric.  [ruby-core:79572] [Bug #13222]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@61361 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 26 insertions, 23 deletions

diff --git a/array.c b/array.c
index 05e6069ad3..724cf46b38 100644
--- a/array.c
+++ b/array.c
@@ -5691,6 +5691,26 @@ rb_ary_dig(int argc, VALUE *argv, VALUE self)
     return rb_obj_dig(argc, argv, self, Qnil);
 }
 
+static inline VALUE
+finish_exact_sum(long n, VALUE r, VALUE v, int z)
+{
+    if (n != 0)
+        v = rb_fix_plus(LONG2FIX(n), v);
+    if (r != Qundef) {
+	/* r can be an Integer when mathn is loaded */
+	if (FIXNUM_P(r))
+	    v = rb_fix_plus(r, v);
+	else if (RB_TYPE_P(r, T_BIGNUM))
+	    v = rb_big_plus(r, v);
+	else
+	    v = rb_rational_plus(r, v);
+    }
+    else if (!n && z) {
+        v = rb_fix_plus(LONG2FIX(0), v);
+    }
+    return v;
+}
+
 /*
  * call-seq:
  *   ary.sum(init=0)                    -> number
@@ -5772,31 +5792,11 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
         else
             goto not_exact;
     }
-    if (n != 0)
-        v = rb_fix_plus(LONG2FIX(n), v);
-    if (r != Qundef) {
-        /* r can be an Integer when mathn is loaded */
-        if (FIXNUM_P(r))
-            v = rb_fix_plus(r, v);
-        else if (RB_TYPE_P(r, T_BIGNUM))
-            v = rb_big_plus(r, v);
-        else
-            v = rb_rational_plus(r, v);
-    }
+    v = finish_exact_sum(n, r, v, argc!=0);
     return v;
 
   not_exact:
-    if (n != 0)
-        v = rb_fix_plus(LONG2FIX(n), v);
-    if (r != Qundef) {
-        /* r can be an Integer when mathn is loaded */
-        if (FIXNUM_P(r))
-            v = rb_fix_plus(r, v);
-        else if (RB_TYPE_P(r, T_BIGNUM))
-            v = rb_big_plus(r, v);
-        else
-            v = rb_rational_plus(r, v);
-    }
+    v = finish_exact_sum(n, r, v, i!=0);
 
     if (RB_FLOAT_TYPE_P(e)) {
         /*
diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index 2701f988e3..42830063b5 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -2839,6 +2839,9 @@ class TestArray < Test::Unit::TestCase
     assert_equal("abc", ["a", "b", "c"].sum(""))
     assert_equal([1, [2], 3], [[1], [[2]], [3]].sum([]))
 
+    assert_raise(TypeError) {[0].sum("")}
+    assert_raise(TypeError) {[1].sum("")}
+
     assert_separately(%w[-rmathn], <<-EOS, ignore_stderr: true)
       assert_equal(6, [1r, 2, 3r].sum)
     EOS
diff --git a/version.h b/version.h
index 42179ba97d..e721ccbd83 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.4.4"
 #define RUBY_RELEASE_DATE "2017-12-20"
-#define RUBY_PATCHLEVEL 208
+#define RUBY_PATCHLEVEL 209
 
 #define RUBY_RELEASE_YEAR 2017
 #define RUBY_RELEASE_MONTH 12