Show the records in Relation#inspect

The reason for removing the previous implementation of `#inspect` was
that it hid from you that you were dealing with a `Relation` rather than
an `Array`.

But it is still useful to be able to see the records, particularly if you're
writing something like the following in tests:

    assert_equal [foo], Post.where(:bar)

If the assertion fails, you want to see what records were actually
loaded.

So this implementation makes it clear that you've got a `Relation`, but
also shows your records.

1 files changed, 5 insertions, 0 deletions

diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 8544d36aa8..7fdd42f150 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -1311,4 +1311,9 @@ class RelationTest < ActiveRecord::TestCase
       relation.merge! where: 'foo'
     end
   end
+
+  test "relations show the records in #inspect" do
+    relation = Post.limit(2)
+    assert_equal "#<ActiveRecord::Relation [#{Post.limit(2).map(&:inspect).join(', ')}]>", relation.inspect
+  end
 end