Fix the encoding of the `present' filter

ldap-client.cabal

@@ -41,3 +41,19 @@ library
     , semigroups    >= 0.16
     , stm
     , text
+
+test-suite spec
+  default-language:
+    Haskell2010
+  type:
+    exitcode-stdio-1.0
+  hs-source-dirs:
+    test
+  main-is:
+    Spec.hs
+  other-modules:
+    Ldap.ClientSpec
+  build-depends:
+      base          >= 4.7 && < 5
+    , hspec
+    , ldap-client

src/Ldap/Asn1/ToAsn1.hs

@@ -201,7 +201,8 @@ instance ToAsn1 Filter where
     Substrings x      -> context 4 (toAsn1 x)
     GreaterOrEqual x  -> context 5 (toAsn1 x)
     LessOrEqual x     -> context 6 (toAsn1 x)
-    Present x         -> context 7 (toAsn1 x)
+    Present (AttributeDescription (LdapString x))
+                      -> other Asn1.Context 7 (Text.encodeUtf8 x)
     ApproxMatch x     -> context 8 (toAsn1 x)
     ExtensibleMatch x -> context 9 (toAsn1 x)
 

test/Ldap/ClientSpec.hs

@@ -0,0 +1,21 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Ldap.ClientSpec (spec) where
+
+import           Data.Monoid ((<>))
+import           Test.Hspec
+
+import           Ldap.Client
+import qualified Ldap.Client as Ldap
+
+
+spec :: Spec
+spec =
+  context "Example stolen from the LDAP package tests" $
+    it "searches the public LDAP server at MIT" $ do
+      res <- Ldap.with (Plain "scripts.mit.edu") 389 $ \l -> do
+        res <- Ldap.search l (Dn "ou=People,dc=scripts,dc=mit,dc=edu")
+                             (scope WholeSubtree <> typesOnly True)
+                             (Present (Attr "uid"))
+                             []
+        res `shouldSatisfy` (not . null)
+      res `shouldBe` Right ()

test/Spec.hs

@@ -0,0 +1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}