{-# LANGUAGE StandaloneDeriving, FlexibleInstances, UndecidableInstances, IncoherentInstances #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Haddock.ParseSpec (main, spec) where

import           Test.Hspec
import           RdrName (RdrName)
import           DynFlags (DynFlags, defaultDynFlags)
import           Haddock.Lex (tokenise)
import           Haddock.Parse (parseParas)
import           Haddock.Types
import           Outputable
import           Data.Monoid

dynFlags :: DynFlags
dynFlags = defaultDynFlags (error "dynFlags for Haddock tests: undefined")

instance Outputable a => Show a where
  show = showSDoc dynFlags . ppr

deriving instance Show a => Show (Doc a)
deriving instance Eq a =>Eq (Doc a)

parse :: String -> Maybe (Doc RdrName)
parse s = parseParas $ tokenise dynFlags s (0,0)

main :: IO ()
main = hspec spec

spec :: Spec
spec = do
  describe "parseParas" $ do

    it "parses a paragraph" $ do
      parse "foobar" `shouldBe` (Just . DocParagraph . DocString) "foobar\n"

    context "when parsing an example" $ do

      it "requires an example to be separated from a previous paragrap by an empty line" $ do
        parse "foobar\n\n>>> fib 10\n55" `shouldBe`
          (Just $ DocAppend (DocParagraph $ DocString "foobar\n") (DocExamples $ [Example "fib 10" ["55"]]))

        -- parse error
        parse "foobar\n>>> fib 10\n55" `shouldBe` Nothing

      it "parses a result line that only contains <BLANKLINE> as an emptly line" $ do
        parse ">>> putFooBar\nfoo\n<BLANKLINE>\nbar" `shouldBe`
          (Just $ DocExamples $ [Example "putFooBar" ["foo","","bar"]])

    context "when parsing a code block" $ do
      it "requires a code blocks to be separated from a previous paragrap by an empty line" $ do
        parse "foobar\n\n> some code" `shouldBe`
          Just (DocAppend (DocParagraph (DocString "foobar\n")) (DocCodeBlock (DocString " some code\n")))

        -- parse error
        parse "foobar\n> some code" `shouldBe` Nothing


    context "when parsing a URL" $ do
      it "parses a URL" $ do
        parse "<http://example.com/>" `shouldBe`
          (Just . DocParagraph $ hyperlink "http://example.com/" Nothing `mappend` DocString "\n")

      it "accepts an optional label" $ do
        parse "<http://example.com/ some link>" `shouldBe`
          (Just . DocParagraph $ hyperlink "http://example.com/" (Just "some link") `mappend` DocString "\n")

    context "when parsing properties" $ do
      it "can parse a single property" $ do
        parse "prop> 23 == 23" `shouldBe` (Just $ DocProperty "23 == 23")

      it "can parse a multiple subsequent properties" $ do
        let input = unlines [
                "prop> 23 == 23"
              , "prop> 42 == 42"
              ]
        parse input `shouldBe` (Just $ DocProperty "23 == 23" `DocAppend` DocProperty "42 == 42")
  where
    hyperlink :: String -> Maybe String -> Doc RdrName
    hyperlink url = DocHyperlink . Hyperlink url