Add a test of the IO class in # clean_input_buffer. Issue rmodbus#35.

The test is needed to avoid calling #flush_input for Socket class in
RTUviaTCPClient.

Author: Aleksey Timin

.gitignore

@@ -7,3 +7,4 @@ html/
 doc/
 Gemfile.lock
 .rvmrc
+tags

lib/rmodbus/rtu.rb

@@ -46,7 +46,11 @@ def read_rtu_response(io)
 
     def clean_input_buff
       # empty the input buffer
-      @io.flush_input
+      if @io.kind_of? SerialPort
+        @io.flush_input 
+      else
+        @io.flush
+      end
     end
 
     def send_rtu_pdu(pdu)

spec/logging_spec.rb

@@ -60,9 +60,12 @@ def mock_query(request, response)
 
       @sp.should_receive(:flow_control=).with(SerialPort::NONE)
       @sp.stub(:read_timeout=)
-      
+      @sp.stub(:kind_of?).with(SerialPort).and_return(true)
+      @sp.stub(:flush_input)
+
       @slave = ModBus::RTUClient.new("/dev/port1", 9600, :data_bits => 7, :stop_bits => 2, :parity => SerialPort::ODD).with_slave(1)
       @slave.read_retries = 0
+
     end
 
     it 'should log rec\send bytes' do

spec/rtu_client_spec.rb

@@ -7,6 +7,7 @@
     SerialPort.should_receive(:new).with("/dev/port1", 9600, 8, 1, 0).and_return(@sp)    
     @sp.stub(:read_timeout=)
     @sp.should_receive(:flow_control=).with(SerialPort::NONE)
+    @sp.stub(:kind_of?).with(SerialPort).and_return(true)
     @sp.stub(:flush_input)
 
     @cl = ModBus::RTUClient.new("/dev/port1", 9600, :data_bits => 8, :stop_bits => 1, :parity => SerialPort::NONE)

spec/rtu_via_tcp_client_spec.rb

@@ -4,10 +4,10 @@
 describe ModBus::RTUViaTCPClient do
   describe "method 'query'" do    
     before do 
-      @sock = double('Socked')
+      @sock = double('Socket')
       TCPSocket.should_receive(:new).with("127.0.0.1", 10002).and_return(@sock)    
       @sock.stub(:read_timeout=)
-      @sock.stub(:flush_input)
+      @sock.stub(:flush)
 
       @cl = ModBus::RTUViaTCPClient.new("127.0.0.1")
       @slave = @cl.with_slave(1)