Test actual sending of data

semantic-diff.cabal

@@ -182,6 +182,7 @@ test-suite test
                      , HUnit
                      , leancheck
                      , mtl
+                     , network
                      , containers
                      , recursion-schemes >= 4.1
                      , semantic-diff

src/Semantic/Stat.hs

@@ -17,8 +17,9 @@ module Semantic.Stat
 , defaultStatsClient
 , StatsClient(..)
 
--- Internal
+-- Internal, exposed for testing
 , renderDatagram
+, sendStats
 ) where
 
 

test/Semantic/StatSpec.hs

@@ -5,6 +5,14 @@ import Test.Hspec hiding (shouldBe, shouldNotBe, shouldThrow, errorCall)
 import Test.Hspec.Expectations.Pretty
 import System.Environment
 import Control.Exception
+import Network.Socket hiding (recv)
+import Network.Socket.ByteString
+
+
+withSocketPair :: ((Socket, Socket) -> IO c) -> IO c
+withSocketPair = bracket create release
+  where create = socketPair AF_UNIX Datagram defaultProtocol
+        release (client, server) = close client >> close server
 
 withEnvironment :: String -> String -> (() -> IO ()) -> IO ()
 withEnvironment key value = bracket (setEnv key value) (const (unsetEnv key))
@@ -59,3 +67,11 @@ spec = do
       it "renders tags without value" $ do
         let inc = increment key [("key", "value"), ("a", "")]
         renderDatagram "" inc `shouldBe` "app.metric:1|c|#key:value,a"
+
+  describe "sendStats" $
+    it "delivers datagram" $ do
+      client@StatsClient{..} <- defaultStatsClient
+      withSocketPair $ \(clientSoc, serverSoc) -> do
+        sendStats client { udpSocket = clientSoc } (increment "app.metric" [])
+        info <- recv serverSoc 1024
+        info `shouldBe` "semantic.app.metric:1|c"