driver was sending hard limits where it should've sent soft, and vice-versa. fix and add tests for this

README.rdoc

@@ -335,6 +335,9 @@ Kyle Banker, banker on github
 Michael Bernstein, mrb on github
 * #sort method for Cursor instances
 
+Paulo Ahahgon, pahagon on github
+* removed hard limit
+
 = License
 
  Copyright 2008-2009 10gen Inc.

lib/mongo/cursor.rb

@@ -173,7 +173,6 @@ module Mongo
     # Collection#find for details.
     def close
       @db.send_to_db(KillCursorsMessage.new(@cursor_id)) if @cursor_id
-      @cache = []
       @cursor_id = 0
       @closed = true
     end
@@ -207,8 +206,15 @@ module Mongo
       @result_flags = header_buf.get_int
       @cursor_id = header_buf.get_long
       @starting_from = header_buf.get_int
-      @n_returned = header_buf.get_int
+      @n_remaining = header_buf.get_int
-      @n_remaining = @n_returned
+      if @n_received
+        @n_received += @n_remaining
+      else
+        @n_received = @n_remaining
+      end
+      if @query.number_to_return > 0 and @n_received >= @query.number_to_return
+        close()
+      end
     end
 
     def num_remaining
@@ -267,7 +273,7 @@ module Mongo
     end
 
     def to_s
-      "DBResponse(flags=#@result_flags, cursor_id=#@cursor_id, start=#@starting_from, n_returned=#@n_returned)"
+      "DBResponse(flags=#@result_flags, cursor_id=#@cursor_id, start=#@starting_from)"
     end
 
     def check_modifiable

lib/mongo/db.rb

@@ -525,8 +525,6 @@ module Mongo
     # DB commands need to be ordered, so selector must be an OrderedHash
     # (or a Hash with only one element). What DB commands really need is
     # that the "command" key be first.
-    #
-    # Do not call this. Intended for driver use only.
     def db_command(selector, use_admin_db=false)
       if !selector.kind_of?(OrderedHash)
         if !selector.kind_of?(Hash) || selector.keys.length > 1
@@ -535,7 +533,7 @@ module Mongo
       end
 
       q = Query.new(selector)
-      q.number_to_return = 1
+      q.number_to_return = -1
       query(Collection.new(self, SYSTEM_COMMAND_COLLECTION), q, use_admin_db).next_object
     end
 

lib/mongo/message/query_message.rb

@@ -31,7 +31,7 @@ module Mongo
       write_int(0)
       write_string("#{db_name}.#{collection_name}")
       write_int(query.number_to_skip)
-      write_int(-query.number_to_return) # Negative means hard limit
+      write_int(query.number_to_return)
       sel = query.selector
       if query.contains_special_fields
         sel = OrderedHash.new

test/test_collection.rb

@@ -216,6 +216,39 @@ class TestCollection < Test::Unit::TestCase
     assert_equal 5, @@test.find({}, :skip => 3, :limit => 5).to_a.length
   end
 
+  def test_large_limit
+    2000.times do |i|
+      @@test.insert("x" => i, "y" => "mongomongo" * 1000)
+    end
+
+    assert_equal 2000, @@test.count
+
+    i = 0
+    y = 0
+    @@test.find({}, :limit => 1900).each do |doc|
+      i += 1
+      y += doc["x"]
+    end
+
+    assert_equal 1900, i
+    assert_equal 1804050, y
+  end
+
+  def test_small_limit
+    @@test.insert("x" => "hello world")
+    @@test.insert("x" => "goodbye world")
+
+    assert_equal 2, @@test.count
+
+    x = 0
+    @@test.find({}, :limit => 1).each do |doc|
+      x += 1
+      assert_equal "hello world", doc["x"]
+    end
+
+    assert_equal 1, x
+  end
+
   def test_group_with_scope
     @@test.save("a" => 1)
     @@test.save("b" => 1)

test/test_cursor.rb

@@ -167,7 +167,6 @@ class CursorTest < Test::Unit::TestCase
   end
 
   def test_refill_via_get_more
-    begin
     assert_equal 1, @@coll.count
     1000.times { |i|
       assert_equal 1 + i, @@coll.count
@@ -191,14 +190,9 @@ class CursorTest < Test::Unit::TestCase
 
     assert_equal count, count2
     assert_equal 499501, count
-    rescue Test::Unit::AssertionFailedError => ex
-      p @@db.collection_names
-      Process.exit 1
-    end
   end
 
   def test_refill_via_get_more_alt_coll
-    begin
     coll = @@db.collection('test-alt-coll')
     coll.clear
     coll.insert('a' => 1)     # collection not created until it's used
@@ -226,10 +220,6 @@ class CursorTest < Test::Unit::TestCase
 
     assert_equal count, count2
     assert_equal 499501, count
-    rescue Test::Unit::AssertionFailedError => ex
-      p @@db.collection_names
-      Process.exit 1
-    end
   end
 
   def test_close_after_query_sent