deprecate DB#count and passing a selector to Collection#count

lib/mongo/collection.rb

@@ -359,10 +359,15 @@ EOS
           @db.collections_info(@name).next_object()['options']
         end
 
-        # Return the number of records that match +selector+. If +selector+ is
-        # +nil+ or an empty hash, returns the count of all records.
-        def count(selector={})
-          @db.count(@name, selector || {})
+        # Get the number of documents in this collection.
+        #
+        # Specifying a +selector+ is DEPRECATED and will be removed. Please use
+        # find(selector).count() instead.
+        def count(selector=nil)
+          if selector
+            warn "specifying a selector for Collection#count is deprecated and will be removed. Please use Collection.find(selector).count instead."
+          end
+          find(selector || {}).count()
         end
 
         protected

lib/mongo/db.rb

@@ -396,17 +396,10 @@ module XGen
           }
         end
 
-        # Return the number of records in +collection_name+ that match
-        # +selector+. If +selector+ is +nil+ or an empty hash, returns the
-        # count of all records. Normally called by Collection#count.
+        # DEPRECATED - use Collection.find(selector).count() instead
         def count(collection_name, selector={})
-          oh = OrderedHash.new
-          oh[:count] = collection_name
-          oh[:query] = selector || {}
-          doc = db_command(oh)
-          return doc['n'].to_i if ok?(doc)
-          return 0 if doc['errmsg'] == "ns missing"
-          raise "Error with count command: #{doc.inspect}"
+          warn "DB#count is deprecated and will be removed. Please use Collection.find(selector).count instead."
+          collection(collection_name).find(selector).count()
         end
 
         # Dereference a DBRef, getting the document it points to.

test/test_collection.rb

@@ -104,9 +104,12 @@ class TestCollection < Test::Unit::TestCase
     @@test.drop
 
     assert_equal 0, @@test.count
-    @@test.save({})
-    @@test.save({})
+    @@test.save("x" => 1)
+    @@test.save("x" => 2)
     assert_equal 2, @@test.count
+
+    # TODO remove this test - it's deprecated
+    assert_equal 1, @@test.count("x" => 1)
   end
 
   def test_find_one

test/test_db_api.rb

@@ -536,8 +536,8 @@ class DBAPITest < Test::Unit::TestCase
     @@coll.insert('a' => 3)
 
     assert_equal 3, @@coll.count
-    assert_equal 1, @@coll.count('$where' => Code.new('this.a > 2'))
-    assert_equal 2, @@coll.count('$where' => Code.new('this.a > i', {'i' => 1}))
+    assert_equal 1, @@coll.find('$where' => Code.new('this.a > 2')).count()
+    assert_equal 2, @@coll.find('$where' => Code.new('this.a > i', {'i' => 1})).count()
   end
 
   def test_eval