3 files changed, 15 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index 6d0fef5929..4e126df614 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Mar  3 17:10:49 2011  Akinori MUSHA  <[email protected]>
+
+	* array.c (rb_ary_collect), enum.c (enum_collect): Add
+	  compatibility warnings for a call without a block.
+
 Fri Feb 18 20:46:55 2011  Shugo Maeda  <[email protected]>
 
 	* lib/fileutils.rb (FileUtils::remove_entry_secure): there is a
diff --git a/array.c b/array.c
index 0ae52f6990..49d4795aad 100644
--- a/array.c
+++ b/array.c
@@ -1902,6 +1902,8 @@ rb_ary_collect(ary)
     VALUE collect;
 
     if (!rb_block_given_p()) {
+	rb_warn("Array#%s without a block does not return an array in 1.9 and later",
+		rb_id2name(rb_frame_last_func()));
 	return rb_ary_new4(RARRAY(ary)->len, RARRAY(ary)->ptr);
     }
 
diff --git a/enum.c b/enum.c
index a1976e32fd..50b34ef16c 100644
--- a/enum.c
+++ b/enum.c
@@ -430,7 +430,14 @@ enum_collect(obj)
 {
     VALUE ary = rb_ary_new();
 
-    rb_iterate(rb_each, obj, rb_block_given_p() ? collect_i : collect_all, ary);
+    if (!rb_block_given_p()) {
+	rb_warn("Enumerable#%s without a block does not return an array in 1.9 and later",
+		rb_id2name(rb_frame_last_func()));
+	rb_iterate(rb_each, obj, collect_all, ary);
+    }
+    else {
+	rb_iterate(rb_each, obj, collect_i, ary);
+    }
 
     return ary;
 }