Initial email header parsing

test/Test/Data/Email/Header.hs

@@ -0,0 +1,36 @@
+module Test.Data.Email.Header where
+
+import Test.Tasty
+import Test.Tasty.Hedgehog
+
+import Hedgehog
+import qualified Hedgehog.Corpus as Corpus
+import qualified Hedgehog.Gen as Gen
+import qualified Hedgehog.Range as Range
+
+import Data.Text
+import qualified Data.Vector as V
+
+import Data.Email.Header
+
+genHeader :: Gen Header
+genHeader = Gen.choice
+  [ From <$> genEmail
+  , To . V.fromList <$> Gen.list (Range.linear 0 10) genEmail
+  ]
+  where
+    genEmail :: Gen Text
+    genEmail = do
+      name <- Gen.element Corpus.simpsons
+      domain <- Gen.element Corpus.cooking
+      tld <- Gen.element ["com","fi","org"]
+      pure $ name <> "@" <> domain <> "." <> tld
+
+prop_roundtrip_parse :: Property
+prop_roundtrip_parse = property $ do
+  header <- forAll genHeader
+  tripping header encode decode
+
+tests :: TestTree
+tests = testGroup "Data.Email.Header"
+  [ testProperty "roundtrip property" $ prop_roundtrip_parse ]