hnix-0.5.2: tests/ReduceExprTests.hs

{-# LANGUAGE OverloadedStrings #-}
{-# OPTIONS_GHC -fno-warn-name-shadowing #-}
module ReduceExprTests (tests) where
import Data.Fix
import Test.Tasty
import Test.Tasty.HUnit

import Nix.Atoms
import Nix.Expr.Types
import Nix.Expr.Types.Annotated
import Nix.Parser
import Nix.Reduce (reduceExpr)


tests :: TestTree
tests = testGroup "Expr Reductions"
    [ testCase "Non nested NSelect on set should be reduced" $ 
        cmpReduceResult selectBasic selectBasicExpect,
      testCase "Nested NSelect on set should be reduced" $ 
        cmpReduceResult selectNested selectNestedExpect,
      testCase "Non nested NSelect with incorrect attrpath shouldn't be reduced" $ 
        shouldntReduce selectIncorrectAttrPath,
      testCase "Nested NSelect with incorrect attrpath shouldn't be reduced" $ 
        shouldntReduce selectNestedIncorrectAttrPath 
    ]

assertSucc :: Result a -> IO a
assertSucc (Success a) = pure a
assertSucc (Failure d) = assertFailure $ show d

cmpReduceResult :: Result NExprLoc -> NExpr -> Assertion 
cmpReduceResult r e = do
    r <- assertSucc r
    r <- stripAnnotation <$> reduceExpr Nothing r
    r @?= e

shouldntReduce :: Result NExprLoc -> Assertion
shouldntReduce r = do
    r <- assertSucc r
    rReduced <- reduceExpr Nothing r
    r @?= rReduced

selectBasic :: Result NExprLoc
selectBasic = parseNixTextLoc "{b=2;a=42;}.a"

selectBasicExpect :: NExpr
selectBasicExpect = Fix . NConstant $ NInt 42

selectNested :: Result NExprLoc
selectNested = parseNixTextLoc "{a={b=2;a=42;};b={a=2;};}.a.a"

selectNestedExpect :: NExpr
selectNestedExpect = Fix . NConstant $ NInt 42

selectIncorrectAttrPath :: Result NExprLoc
selectIncorrectAttrPath = parseNixTextLoc "{a=42;}.b"

selectNestedIncorrectAttrPath :: Result NExprLoc
selectNestedIncorrectAttrPath = parseNixTextLoc "{a={a=42;};}.a.b"