Haskell - コードの整理とプロジェクトのビルド - QuickCheckを使ったプロパティテスト - 対応する型の範囲を広げる, quickcheck-instancesパッケージ

開発環境

入門Haskellプログラミング (Will Kurt(著)、株式会社クイープ(監修、翻訳)、翔泳社)の UNIT6(コードの整理とプロジェクトのビルド)、LESSON 36(QuickCHeckを使ったプロパティテスト)、36.5(練習問題)、 Q36-1の解答を求めてみる。

軽量マークアップ言語

palindrome-testing/package.yaml

name:                palindrome-testing
version:             0.1.0.0
github:              "githubuser/palindrome-testing"
license:             BSD-3-Clause
author:              "Author name here"
maintainer:          "example@example.com"
copyright:           "2025 Author name here"

extra-source-files:
- README.md
- CHANGELOG.md

# Metadata used when publishing your package
# synopsis:            Short description of your package
# category:            Web

# To avoid duplicated efforts in documentation and dealing with the
# complications of embedding Haddock markup inside cabal files, it is
# common to point users to the README.md file.
description:         Please see the README on GitHub at <https://github.com/githubuser/palindrome-testing#readme>

dependencies:
- base >= 4.7 && < 5
- text
- QuickCheck
- quickcheck-instances

ghc-options:
- -Wall
- -Wcompat
- -Widentities
- -Wincomplete-record-updates
- -Wincomplete-uni-patterns
- -Wmissing-export-lists
- -Wmissing-home-modules
- -Wpartial-fields
- -Wredundant-constraints

default-extensions:
  - OverloadedStrings

library:
  source-dirs: src

executables:
  palindrome-testing-exe:
    main:                Main.hs
    source-dirs:         app
    ghc-options:
    - -threaded
    - -rtsopts
    - -with-rtsopts=-N
    dependencies:
    - palindrome-testing

tests:
  palindrome-testing-test:
    main:                Spec.hs
    source-dirs:         test
    ghc-options:
    - -threaded
    - -rtsopts
    - -with-rtsopts=-N
    dependencies:
    - palindrome-testing

コード

palindrome-testing/src/Lib.hs

module Lib (isPalindrome, preProcess) where
import qualified Data.Text as T
import Data.Char (isSpace,isPunctuation)

stripWhiteSpace :: T.Text -> T.Text
stripWhiteSpace = T.filter (not . isSpace)

stripPuctuation :: T.Text -> T.Text
stripPuctuation = T.filter (not . isPunctuation)

preProcess :: T.Text -> T.Text
preProcess = stripWhiteSpace . stripPuctuation . T.toLower

isPalindrome :: T.Text -> Bool
isPalindrome text = cleanText == T.reverse cleanText
    where cleanText = preProcess text

palindrome-testing/test/Spec.hs

import Lib
import Data.Char(isSpace,isPunctuation)
import Test.QuickCheck
import Test.QuickCheck.Instances()
import qualified Data.Text as T

prop_whitespaceInvariant :: T.Text -> Bool
prop_whitespaceInvariant text =
    let noSpacText = T.filter (not . isSpace) text
    in preProcess text == preProcess noSpacText

prop_punctuationInvariant :: T.Text -> Bool
prop_punctuationInvariant text = 
    let noPuncText = T.filter (not . isPunctuation) text
    in preProcess text == preProcess noPuncText

prop_upperInvariant :: T.Text -> Bool
prop_upperInvariant text =
    let upper = T.toUpper text
    in preProcess text == preProcess upper

prop_lowerInvariant :: T.Text -> Bool
prop_lowerInvariant text =
    let lower = T.toLower text
    in preProcess text == preProcess lower

prop_reverseInvarient :: T.Text -> Bool
prop_reverseInvarient text = isPalindrome text == isPalindrome (T.reverse text)

main :: IO ()
main = do
    quickCheck prop_whitespaceInvariant
    quickCheck prop_punctuationInvariant
    quickCheck prop_upperInvariant
    quickCheck prop_lowerInvariant
    quickCheck prop_reverseInvarient
    putStrLn "done!"

入出力結果(Terminal, Zsh)

% stack test
palindrome-testing> build (lib + exe + test) with ghc-9.8.4
Preprocessing library for palindrome-testing-0.1.0.0..
Building library for palindrome-testing-0.1.0.0..
[1 of 2] Compiling Lib [Source file changed]
Preprocessing executable 'palindrome-testing-exe' for palindrome-testing-0.1.0.0..
Building executable 'palindrome-testing-exe' for palindrome-testing-0.1.0.0..
Preprocessing test suite 'palindrome-testing-test' for palindrome-testing-0.1.0.0..
Building test suite 'palindrome-testing-test' for palindrome-testing-0.1.0.0..
palindrome-testing> copy/register
Installing library in /Users/.../palindrome-testing/.stack-work/install/aarch64-osx/e7436b3217cf53d6b9beeebd2bdc5dd8dcab6f8595b8bde259631442ce745f25/9.8.4/lib/aarch64-osx-ghc-9.8.4/palindrome-testing-0.1.0.0-Jc7lOYEDWk94e4Cs0gDnxC
Installing executable palindrome-testing-exe in /Users/.../palindrome-testing/.stack-work/install/aarch64-osx/e7436b3217cf53d6b9beeebd2bdc5dd8dcab6f8595b8bde259631442ce745f25/9.8.4/bin
Registering library for palindrome-testing-0.1.0.0..
palindrome-testing> test (suite: palindrome-testing-test)
                                
+++ OK, passed 100 tests.
+++ OK, passed 100 tests.
+++ OK, passed 100 tests.
+++ OK, passed 100 tests.
+++ OK, passed 100 tests.
done!



palindrome-testing> Test suite palindrome-testing-test passed
Completed 2 action(s).
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