array.c: keep consistency

* array.c (rb_ary_select_bang): keep the array consistent by
  removing unselected values soon.  [ruby-dev:48805] [Bug #10722]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49196 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 12 deletions

diff --git a/array.c b/array.c
index 00d2a7f6a8..0de7231121 100644
--- a/array.c
+++ b/array.c
@@ -2843,23 +2843,22 @@ rb_ary_select(VALUE ary)
 static VALUE
 rb_ary_select_bang(VALUE ary)
 {
-    long i1, i2;
+    long i;
+    VALUE result = Qnil;
 
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     rb_ary_modify(ary);
-    for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); i1++) {
-	VALUE v = RARRAY_AREF(ary, i1);
-	if (!RTEST(rb_yield(v))) continue;
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, v);
+    for (i = 0; i < RARRAY_LEN(ary); ) {
+	VALUE v = RARRAY_AREF(ary, i);
+	if (!RTEST(rb_yield(v))) {
+	    rb_ary_delete_at(ary, i);
+	    result = ary;
+	}
+	else {
+	    i++;
 	}
-	i2++;
     }
-
-    if (i1 == i2) return Qnil;
-    if (i2 < i1)
-	ARY_SET_LEN(ary, i2);
-    return ary;
+    return result;
 }
 
 /*