module Data.Cfg.FollowSetTests
  ( tests
  ) where

import Data.Cfg.Analysis
import Data.Cfg.Augment
import Data.Cfg.LookaheadSet
import Data.Cfg.TestGrammars
import Test.Framework (Test, testGroup)
import Test.Framework.Providers.HUnit (testCase)
import Test.HUnit (assertEqual)

tests :: Test
tests = testGroup "Data.Cfg.FollowSet" [g0FollowSetTest, microFollowSetTest]

g0FollowSetTest :: Test
g0FollowSetTest = testCase "g0 follow-set test" $ mapM_ f tab
  where
    f :: (String, LookaheadSet String) -> IO ()
    f (nt, expected) = assertEqual msg expected (fols $ AugNT nt)
      where
        msg = "g0: followSet(" ++ nt ++ ")"
    tab :: [(String, LookaheadSet String)]
    tab =
      [ ("e", mkLookaheadSet True ["RPAREN"])
      , ("prefix", mkLookaheadSet False ["LPAREN"])
      , ("tail", mkLookaheadSet True ["RPAREN"])
      ]
    fols :: AugNT String -> LookaheadSet String
    fols = followSet g0Analysis

microFollowSetTest :: Test
microFollowSetTest = testCase "micro follow-set test" $ mapM_ f tab
  where
    f :: (String, LookaheadSet String) -> IO ()
    f (nt, expected) = assertEqual msg expected (fols $ AugNT nt)
      where
        msg = "micro: followSet(" ++ nt ++ ")"
    tab :: [(String, LookaheadSet String)]
    tab =
      [ ("program", mkLookaheadSet True [])
      , ("statement_list", mkLookaheadSet False $ words "END")
      , ("statement", mkLookaheadSet False $ words "ID READ WRITE END")
      , ("statement_tail", mkLookaheadSet False $ words "END")
      , ("expression", mkLookaheadSet False $ words "COMMA SEMI RPAREN")
      , ("id_list", mkLookaheadSet False $ words "RPAREN")
      , ("expr_list", mkLookaheadSet False $ words "RPAREN")
      , ("id_tail", mkLookaheadSet False $ words "RPAREN")
      , ("expr_tail", mkLookaheadSet False $ words "RPAREN")
      , ("primary", mkLookaheadSet False $ words "COMMA SEMI PLUS MINUS RPAREN")
      , ("primary_tail", mkLookaheadSet False $ words "COMMA SEMI RPAREN")
      , ("add_op", mkLookaheadSet False $ words "ID INT_LITERAL LPAREN")
      ]
    fols :: AugNT String -> LookaheadSet String
    fols = followSet microAnalysis