DefaultTest.hs

{-# LANGUAGE NoImplicitPrelude   #-}
{-# LANGUAGE OverloadedStrings   #-}
{-# LANGUAGE ScopedTypeVariables #-}
module System.Etc.Resolver.DefaultTest (tests) where

import           RIO
import qualified RIO.Set as Set

import qualified Data.Aeson       as JSON
import           Test.Tasty       (TestTree, testGroup)
import           Test.Tasty.HUnit (assertBool, assertFailure, testCase)

import System.Etc

assertDefaultValue :: Config -> [Text] -> Value JSON.Value -> IO ()
assertDefaultValue config keys val = case getAllConfigSources keys config of
  Nothing   -> assertFailure ("expecting to get entries for greeting\n" <> show config)
  Just aSet -> assertBool ("expecting to see entry from env; got " <> show aSet)
                          (Set.member (Default val) aSet)

tests :: TestTree
tests = testGroup
  "default"
  [ testCase "default is used when defined on spec" $ do
    let input = mconcat
          [ "{\"etc/entries\": {"
          , " \"greeting\": { \"etc/spec\": { \"default\": \"hello default 1\" }}}}"
          ]

    (spec :: ConfigSpec ()) <- parseConfigSpec input
    let config = resolveDefault spec
    assertDefaultValue config ["greeting"] "hello default 1"
  , testCase "default can be raw JSON value on entries spec" $ do
    let input = mconcat ["{\"etc/entries\": {", " \"greeting\": \"hello default 2\"}}"]
    (spec :: ConfigSpec ()) <- parseConfigSpec input

    let config = resolveDefault spec
    assertDefaultValue config ["greeting"] "hello default 2"
  , testCase "default can be a null JSON value" $ do
    let input = mconcat ["{\"etc/entries\": {", " \"greeting\": null}}"]
    (spec :: ConfigSpec ()) <- parseConfigSpec input

    let config = resolveDefault spec

    case getAllConfigSources ["greeting"] config of
      Nothing   -> assertFailure ("expecting to get entries for greeting\n" <> show config)
      Just aSet -> assertBool ("expecting to see entry from env; got " <> show aSet)
                              (Set.member (Default $ Plain JSON.Null) aSet)
  ]