Do not try to insert 0{40} objects

We use them as an obviously bogus value, but part of hardening the objectdb
paths we no longer allow all-zero object names, so use a slightly different
obviously bogus name instead.

Author: carlosmn

test/tree_test.rb

@@ -192,24 +192,24 @@ def test_tree_updater_remove
   def test_treebuilder_add_nonexistent_fails
     builder = Rugged::Tree::Builder.new(@repo, @repo.head.target.tree)
     assert_raises Rugged::TreeError do
-      builder << { :type => :blob, :name => "another-readme", :oid => "0000000000000000000000000000000000000000", :filemode => 0100644 }
+      builder << { :type => :blob, :name => "another-readme", :oid => "0000000000000000000000000000000000000001", :filemode => 0100644 }
     end
   end
 
   def test_treebuilder_add_submodules_always_succeeds
     builder = Rugged::Tree::Builder.new(@repo, @repo.head.target.tree)
-    builder << { :type => :commit, :name => "submodule", :oid => "0000000000000000000000000000000000000000", :filemode => 0160000 }
+    builder << { :type => :commit, :name => "submodule", :oid => "0000000000000000000000000000000000000001", :filemode => 0160000 }
     newtree = builder.write
-    assert_equal "ce986db11f99880a0a087ba3220dba61e9afd918", newtree
+    assert_equal "731d4e5d79f60ed64687b7828e1d0528839fed6e", newtree
   end
 
   def test_treebuilder_add_nonexistent_can_pass
     begin
       Rugged::Settings['strict_object_creation'] = false
       builder = Rugged::Tree::Builder.new(@repo, @repo.head.target.tree)
-      builder << { :type => :blob, :name => "another-readme", :oid => "0000000000000000000000000000000000000000", :filemode => 0100644 }
+      builder << { :type => :blob, :name => "another-readme", :oid => "0000000000000000000000000000000000000001", :filemode => 0100644 }
       newtree = builder.write
-      assert_equal "7c98360ac03064bb67c6f0949e6a354155ce1b04", newtree
+      assert_equal "2e34ce696ea8d595b62b99ac20406f86c15d464a", newtree
     ensure
       Rugged::Settings['strict_object_creation'] = true
     end