なんとなくHaskellが気になったので、どんな感じなのか軽く触ってみることにした。
まずは、動かせる環境を適当で良いから作ってみる。
色々試しやすいように、テストをかけるところまでやってみた。
環境
とりあえず、すぐに動かしたいので、Docker x VSCodeで適当に環境を作った。
できたDockerfile, docker-compose.yml, devcontainer.jsonは、以下参照。
環境補足
VSCodeの拡張機能があったのでインストール。
Dockerイメージは、何も考えずlatestを使用。
doctestのパッケージがあったのでインストール。
VSCodeの拡張機能にGHCupが必要らしいので、インストール。
VSCodeの拡張機能にhaskell language server(hls)が必要らしいので、インストール。
2023/03/18時点だと、version 1.9.1.0が必要だった。
ghcup install hls 1.9.1.0
プロジェクト作成
stackとcabalの2種類があるっぽい。cabalを使ってみた。
※プロジェクト名にアンダースコアを使用すると、プロジェクト作成は通るけど、cabal testとかcabal runで落ちた。
mkdir -p プロジェクト用のディレクトリパス
cd プロジェクト用のディレクトリパス
cabal update
cabal init
cabal initの選択項目は以下のようにした。
What does the package build:
1) Library
* 2) Executable
3) Library and Executable
4) Test suite
Your choice? [default: Executable] 3
Do you wish to overwrite existing files (backups will be created) (y/n)? [default: n] y
Please choose version of the Cabal specification to use:
1) 1.24 (legacy)
2) 2.0 (+ support for Backpack, internal sub-libs, '^>=' operator)
3) 2.2 (+ support for 'common', 'elif', redundant commas, SPDX)
4) 2.4 (+ support for '**' globbing)
* 5) 3.0 (+ set notation for ==, common stanzas in ifs, more redundant commas, better pkgconfig-depends)
6) 3.4 (+ sublibraries in 'mixins', optional 'default-language')
Your choice? [default: 3.0]
Package name? [default: helloworld]
Package version? [default: 0.1.0.0]
Please choose a license:
1) BSD-2-Clause
2) BSD-3-Clause
3) Apache-2.0
4) MIT
5) MPL-2.0
6) ISC
7) GPL-2.0-only
8) GPL-3.0-only
9) LGPL-2.1-only
10) LGPL-3.0-only
11) AGPL-3.0-only
12) GPL-2.0-or-later
13) GPL-3.0-or-later
14) LGPL-2.1-or-later
15) LGPL-3.0-or-later
16) AGPL-3.0-or-later
17) Other (specify)
Your choice? 4
Author name? [default: xxxx]
Maintainer email? [default: xxxx]
Project homepage URL? [optional]
Project synopsis? [optional]
Project category:
1) Codec
2) Concurrency
3) Control
4) Data
5) Database
6) Development
7) Distribution
8) Game
9) Graphics
10) Language
11) Math
12) Network
13) Sound
14) System
15) Testing
16) Text
17) Web
18) Other (specify)
Your choice? [default: (none)]
Library source directory:
* 1) src
2) lib
3) src-lib
4) Other (specify)
Your choice? [default: src]
Choose a language for your library:
* 1) Haskell2010
2) Haskell98
3) GHC2021 (requires at least GHC 9.2)
4) Other (specify)
Your choice? [default: Haskell2010]
What is the main module of the executable:
* 1) Main.hs
2) Main.lhs
3) Other (specify)
Your choice? [default: Main.hs]
Application directory:
* 1) app
2) exe
3) src-exe
4) Other (specify)
Your choice? [default: app]
Choose a language for your executable:
* 1) Haskell2010
2) Haskell98
3) GHC2021 (requires at least GHC 9.2)
4) Other (specify)
Your choice? [default: Haskell2010]
Should I generate a test suite for the library? [default: y]
What is the main module of the test suite?:
* 1) Main.hs
2) Main.lhs
3) Other (specify)
Your choice? [default: Main.hs]
Test directory? [default: test]
Choose a language for your test suite:
* 1) Haskell2010
2) Haskell98
3) GHC2021 (requires at least GHC 9.2)
4) Other (specify)
Your choice? [default: Haskell2010]
Add informative comments to each field in the cabal file. (y/n)? [default: y]
[Log] Using cabal specification: 3.0
[Log] Creating fresh file LICENSE...
[Log] Creating fresh file CHANGELOG.md...
[Log] Creating fresh directory ./src...
[Log] Creating fresh file src/MyLib.hs...
[Log] Creating fresh directory ./app...
[Log] Creating fresh file app/Main.hs...
[Log] Creating fresh directory ./test...
[Log] Creating fresh file test/Main.hs...
[Log] Creating fresh file helloworld.cabal...
[Warning] No synopsis given. You should edit the .cabal file and add one.
[Info] You may want to edit the .cabal file and add a Description field.
ビルド & 実行
cabal initでプロジェクトを作成した状態で、標準出力に"Hello, Haskell!"を出力するソースになっている。
cabal runで、ビルド & 実行できる。
root@f3d42513a02c:/workspace/projects/helloworld# cabal run
Resolving dependencies...
Build profile: -w ghc-9.4.4 -O1
In order, the following will be built (use -v for more details):
- helloworld-0.1.0.0 (lib) (first run)
- helloworld-0.1.0.0 (exe:helloworld) (first run)
Configuring library for helloworld-0.1.0.0..
Preprocessing library for helloworld-0.1.0.0..
Building library for helloworld-0.1.0.0..
[1 of 1] Compiling MyLib ( src/MyLib.hs, /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/build/MyLib.o, /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/build/MyLib.dyn_o )
Configuring executable 'helloworld' for helloworld-0.1.0.0..
Preprocessing executable 'helloworld' for helloworld-0.1.0.0..
Building executable 'helloworld' for helloworld-0.1.0.0..
[1 of 1] Compiling Main ( app/Main.hs, /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/x/helloworld/build/helloworld/helloworld-tmp/Main.o )
[2 of 2] Linking /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/x/helloworld/build/helloworld/helloworld
Hello, Haskell!
someFunc
root@f3d42513a02c:/workspace/projects/helloworld#
テスト
cabal testでテストを実行できる。
doctest
-
cabalファイルにdoctestの構成を追加する。
test-suite doctest type: exitcode-stdio-1.0 default-language: Haskell2010 hs-source-dirs: test/doctest ghc-options: -Wall main-is: doctest.hs build-depends: base , doctest -
cabalファイルの
main-isに指定したソースを作成する。module Main where import Test.DocTest main :: IO () main = doctest ["src/MyLib.hs", "app/Main.hs"] -
doctestを書く。以下は、app/Main.hsのmain関数に書く場合の例
-
テスト追加前
main :: IO () main = do putStrLn "Hello, Haskell!" MyLib.someFunc -
テスト追加後
-- | -- Entry point -- >>> main -- Hello, Haskell! -- someFunc main :: IO () main = do putStrLn "Hello, Haskell!" MyLib.someFunc
-
-
cabal testでテストを実行するroot@8c6481710a1b:/workspace/projects/helloworld# cabal test; echo $? Build profile: -w ghc-9.4.4 -O1 In order, the following will be built (use -v for more details): - helloworld-0.1.0.0 (test:doctest) (first run) - helloworld-0.1.0.0 (test:helloworld-test) (first run) Preprocessing test suite 'doctest' for helloworld-0.1.0.0.. Preprocessing test suite 'helloworld-test' for helloworld-0.1.0.0.. Building test suite 'helloworld-test' for helloworld-0.1.0.0.. Building test suite 'doctest' for helloworld-0.1.0.0.. Running 1 test suites... Test suite helloworld-test: RUNNING... Test suite helloworld-test: PASS Test suite logged to: /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/helloworld-test/test/helloworld-0.1.0.0-helloworld-test.log 1 of 1 test suites (1 of 1 test cases) passed. Running 1 test suites... Test suite doctest: RUNNING... Test suite doctest: PASS Test suite logged to: /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/doctest/test/helloworld-0.1.0.0-doctest.log 1 of 1 test suites (1 of 1 test cases) passed. 0 root@8c6481710a1b:/workspace/projects/helloworld#
テストにNGがあるときは、以下のような出力になる。
root@8c6481710a1b:/workspace/projects/helloworld# cabal test; echo $?
Build profile: -w ghc-9.4.4 -O1
In order, the following will be built (use -v for more details):
- helloworld-0.1.0.0 (test:doctest) (first run)
- helloworld-0.1.0.0 (test:helloworld-test) (first run)
Preprocessing test suite 'helloworld-test' for helloworld-0.1.0.0..
Preprocessing test suite 'doctest' for helloworld-0.1.0.0..
Building test suite 'helloworld-test' for helloworld-0.1.0.0..
Building test suite 'doctest' for helloworld-0.1.0.0..
Running 1 test suites...
Test suite helloworld-test: RUNNING...
Test suite helloworld-test: PASS
Test suite logged to:
/workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/helloworld-test/test/helloworld-0.1.0.0-helloworld-test.log
1 of 1 test suites (1 of 1 test cases) passed.
Running 1 test suites...
Test suite doctest: RUNNING...
app/Main.hs:7: failure in expression `main'
expected: Hello, Haskell
someFunc
but got: Hello, Haskell!
^
someFunc
Examples: 2 Tried: 2 Errors: 0 Failures: 1
Test suite doctest: FAIL
Test suite logged to:
/workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/doctest/test/helloworld-0.1.0.0-doctest.log
0 of 1 test suites (0 of 1 test cases) passed.
Error: cabal: Tests failed for test:doctest from helloworld-0.1.0.0.
1
root@8c6481710a1b:/workspace/projects/helloworld#
HSpec
-
cabalファイルにHSpecの構成を追加する。
test-suite spec type: exitcode-stdio-1.0 default-language: Haskell2010 hs-source-dirs: test/hspec ghc-options: -Wall main-is: Spec.hs build-depends: base , hspec >= 1.3 , QuickCheck , helloworld other-modules: MyLibSpec build-tool-depends: , hspec-discover:hspec-discover -
cabalファイルの
main-isに指定したtest/hspec/Spec.hsを作成する。{-# OPTIONS_GHC -F -pgmF hspec-discover #-} -
test/hspec/MyLibSpec.hsにテストコードを書く。試しにInt二つを引数にし、足した結果を返す関数を対象にした。module MyLibSpec (spec) where import Test.Hspec import MyLib spec :: Spec spec = do describe "`addInt` takes two arguments of Int and returns the result of adding them." $ do it "When give addInt 1 and 2 then return 3" $ MyLib.addInt 1 2 `shouldBe` 3 -
src/MyLib.hsにテスト対象関数を書き足す。module MyLib (someFunc, addInt) where (省略) addInt :: Int -> Int -> Int addInt x y = x + y -
cabal testでテストを実行するroot@5499af50db5b:/workspace/projects/helloworld# cabal test; echo $?; Build profile: -w ghc-9.4.4 -O1 In order, the following will be built (use -v for more details): - helloworld-0.1.0.0 (test:doctest) (first run) - helloworld-0.1.0.0 (test:helloworld-test) (first run) - helloworld-0.1.0.0 (test:spec) (first run) Preprocessing test suite 'spec' for helloworld-0.1.0.0.. Preprocessing test suite 'doctest' for helloworld-0.1.0.0.. Preprocessing test suite 'helloworld-test' for helloworld-0.1.0.0.. Building test suite 'helloworld-test' for helloworld-0.1.0.0.. Building test suite 'doctest' for helloworld-0.1.0.0.. Building test suite 'spec' for helloworld-0.1.0.0.. Running 1 test suites... Test suite helloworld-test: RUNNING... Test suite helloworld-test: PASS Test suite logged to: /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/helloworld-test/test/helloworld-0.1.0.0-helloworld-test.log 1 of 1 test suites (1 of 1 test cases) passed. Running 1 test suites... Test suite doctest: RUNNING... Running 1 test suites... Test suite spec: RUNNING... Test suite spec: PASS Test suite logged to: /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/spec/test/helloworld-0.1.0.0-spec.log 1 of 1 test suites (1 of 1 test cases) passed. Test suite doctest: PASS Test suite logged to: /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/doctest/test/helloworld-0.1.0.0-doctest.log 1 of 1 test suites (1 of 1 test cases) passed. 0 root@5499af50db5b:/workspace/projects/helloworld#
テストにNGがあるときは、以下のような出力になる。
root@5499af50db5b:/workspace/projects/helloworld# cabal test; echo $?;
Build profile: -w ghc-9.4.4 -O1
In order, the following will be built (use -v for more details):
- helloworld-0.1.0.0 (test:doctest) (first run)
- helloworld-0.1.0.0 (test:helloworld-test) (first run)
- helloworld-0.1.0.0 (test:spec) (file test/hspec/MyLibSpec.hs changed)
Preprocessing test suite 'doctest' for helloworld-0.1.0.0..
Preprocessing test suite 'helloworld-test' for helloworld-0.1.0.0..
Preprocessing test suite 'spec' for helloworld-0.1.0.0..
Building test suite 'doctest' for helloworld-0.1.0.0..
Building test suite 'helloworld-test' for helloworld-0.1.0.0..
Building test suite 'spec' for helloworld-0.1.0.0..
[1 of 2] Compiling MyLibSpec ( test/hspec/MyLibSpec.hs, /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/spec/build/spec/spec-tmp/MyLibSpec.o ) [Source file changed]
Running 1 test suites...
Test suite helloworld-test: RUNNING...
[2 of 2] Compiling Main ( test/hspec/Spec.hs, /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/spec/build/spec/spec-tmp/Main.o ) [MyLibSpec changed]
Test suite helloworld-test: PASS
Test suite logged to:
/workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/helloworld-test/test/helloworld-0.1.0.0-helloworld-test.log
1 of 1 test suites (1 of 1 test cases) passed.
Running 1 test suites...
Test suite doctest: RUNNING...
[3 of 3] Linking /workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/spec/build/spec/spec [Objects changed]
Test suite doctest: PASS
Test suite logged to:
/workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/doctest/test/helloworld-0.1.0.0-doctest.log
1 of 1 test suites (1 of 1 test cases) passed.
Running 1 test suites...
Test suite spec: RUNNING...
MyLib
`addInt` takes two arguments of Int and returns the result of adding them.
When give addInt 1 and 2 then return 3 [✘]
Failures:
test/hspec/MyLibSpec.hs:10:30:
1) MyLib, `addInt` takes two arguments of Int and returns the result of adding them., When give addInt 1 and 2 then return 3
expected: 2
but got: 3
To rerun use: --match "/MyLib/`addInt` takes two arguments of Int and returns the result of adding them./When give addInt 1 and 2 then return 3/"
Randomized with seed 1699898266
Finished in 0.0184 seconds
1 example, 1 failure
Test suite spec: FAIL
Test suite logged to:
/workspace/projects/helloworld/dist-newstyle/build/x86_64-linux/ghc-9.4.4/helloworld-0.1.0.0/t/spec/test/helloworld-0.1.0.0-spec.log
0 of 1 test suites (0 of 1 test cases) passed.
Error: cabal: Tests failed for test:spec from helloworld-0.1.0.0.
1
root@5499af50db5b:/workspace/projects/helloworld#
参考
その他参照したもの。