Two executables in one cabal file; stack build does not recognize them - haskell

I'm trying to make 2 executables "project". All duplicates of this question did not help me - their answers don't fix my problem. I have .cabal file like this:
name: int-tests
version: 0.1.0.0
synopsis: Integration Tests Suite
description: Integration Tests Suite
license: AllRightsReserved
author: Author name here
maintainer: example#example.com
copyright: 2018 Author name here
build-type: Custom
extra-source-files: README.md
cabal-version: >=1.10
library
hs-source-dirs: common
exposed-modules: Common
build-depends: base
, text
, aeson
, network-uri
default-language: Haskell2010
ghc-options: -Wall -Werror
executable api-tests-exe
hs-source-dirs: api
main-is: Main.hs
ghc-options: -threaded -rtsopts -with-rtsopts=-N -Wall -Werror
build-depends: base
, hspec
, QuickCheck
default-language: Haskell2010
executable e2e-tests-exe
hs-source-dirs: e2e
main-is: Main.hs
ghc-options: -threaded -rtsopts -with-rtsopts=-N -Wall -Werror
build-depends: base
, hspec
, QuickCheck
default-language: Haskell2010
and when I call stack ide targets I don't see these 2 targets. So, stack build api-tests and stack build e2e-tests don't work too.
How can I create 2 targets' project for stack? I tried also package.yaml but result is the same. Stack version is 1.9.1. I have folders tree like:
api/
...
e2e/
...
where are Main.hs files with content like:
module Main (main) where
main :: IO ()
main = print "Hello"
Also I tried option -main-is Main but without success.
Error looks like:
Error: While constructing the build plan, the following exceptions were encountered:
Unknown package: api-tests

AFAIK, stack build always builds all your targets. But if you want to be run just one executable, you'll need the full name including the -exe. So, stack exec api-tests-exe and stack exec e2e-tests-exe.
But what you really want to do is make these test targets: https://www.haskell.org/cabal/users-guide/developing-packages.html#test-suites

Problem was in stack.yaml file, I had to add '.' folder to "packages:" section.

Related

stack setup won't recognize changes in .cabal file

I've added "QuickCheck" to the "build depends" section of the .cabal file but when I do stack setup the "QuickCheck" section of the file gets removed and I get this error:
It is a member of the hidden package ‘Cabal-3.2.1.0’.
You can run ‘:set -package Cabal’ to expose it.
(Note: this unloads all the modules in the current scope.)
Use -v (or `:set -v` in ghci) to see a list of the files searched for.
|
1 | import Distribution.Simple
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
the stack build and stack ghci work fine but stack test gives this error:
Could not find module ‘Test.QuickCheck’
Use -v (or `:set -v` in ghci) to see a list of the files searched for.
|
3 | import Test.QuickCheck
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Progress 1/2
-- While building package palindrome-testing-0.1.0.0 (scroll up to its section to see the error) using:
/Users/artin/.stack/setup-exe-cache/aarch64-osx/Cabal-simple_mPHDZzAJ_3.2.1.0_ghc-8.10.7 --builddir=.stack-work/dist/aarch64-osx/Cabal-3.2.1.0 build lib:palindrome-testing exe:palindrome-testing-exe test:palindrome-testing-test --ghc-options " -fdiagnostics-color=always"
Process exited with code: ExitFailure 1
.cabal file:
cabal-version: 1.12
-- This file has been generated from package.yaml by hpack version 0.34.6.
--
-- see: https://github.com/sol/hpack
name: palindrome-testing
version: 0.1.0.0
description: Please see the README on GitHub at <https://github.com/githubuser/palindrome-testing#readme>
homepage: https://github.com/githubuser/palindrome-testing#readme
bug-reports: https://github.com/githubuser/palindrome-testing/issues
author: Author name here
maintainer: example#example.com
copyright: 2022 Author name here
license: BSD3
license-file: LICENSE
build-type: Simple
extra-source-files:
README.md
ChangeLog.md
source-repository head
type: git
location: https://github.com/githubuser/palindrome-testing
library
exposed-modules:
Lib
other-modules:
Paths_palindrome_testing
hs-source-dirs:
src
build-depends:
base >=4.7 && <5
default-language: Haskell2010
executable palindrome-testing-exe
main-is: Main.hs
other-modules:
Paths_palindrome_testing
hs-source-dirs:
app
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, palindrome-testing
default-language: Haskell2010
test-suite palindrome-testing-test
type: exitcode-stdio-1.0
main-is: Spec.hs
other-modules:
Paths_palindrome_testing
hs-source-dirs:
test
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, palindrome-testing
, QuickCheck
default-language: Haskell2010
ghc version: 8.10.7
stack version: 2.7.4
cabal version: 3.6.2
I'm running macOS monterey on M1
Your cabal file was generated from the package.yaml file in that directory:
-- This file has been generated from package.yaml by hpack version 0.34.6.
--
-- see: https://github.com/sol/hpack
If you want to add new dependencies, add them to package.yaml. Any changes you make to the .cabal file will get overridden.

Stack auto-removes dependency from .cabal file following 'stack build'

I want to work on a new Haskell project using the threepenny-gui package.
The first thing I did was create a stack project via $ stack new threepennydemo. From here, here, I did the following:
I edited the extra-deps section in my stack.yaml file from:
# extra-deps: []
to
extra-deps:
- threepenny-gui-0.9.0.0
I edited the .cabal file from:
library
exposed-modules:
Lib
other-modules:
Paths_threepennydemo
hs-source-dirs:
src
build-depends:
base >=4.7 && <5
default-language: Haskell2010
executable threepennydemo-exe
main-is: Main.hs
other-modules:
Paths_threepennydemo
hs-source-dirs:
app
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, threepennydemo
default-language: Haskell2010
test-suite threepennydemo-test
type: exitcode-stdio-1.0
main-is: Spec.hs
other-modules:
Paths_threepennydemo
hs-source-dirs:
test
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, threepennydemo
default-language: Haskell2010
to
library
exposed-modules:
Lib
other-modules:
Paths_threepennydemo
hs-source-dirs:
src
build-depends:
base >=4.7 && <5
, threepenny-gui >= 0.9
default-language: Haskell2010
executable threepennydemo-exe
main-is: Main.hs
other-modules:
Paths_threepennydemo
hs-source-dirs:
app
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, threepennydemo
, threepenny-gui >= 0.9
default-language: Haskell2010
test-suite threepennydemo-test
type: exitcode-stdio-1.0
main-is: Spec.hs
other-modules:
Paths_threepennydemo
hs-source-dirs:
test
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, threepennydemo
, threepenny-gui >= 0.9
default-language: Haskell2010
I edited the stock /app/Main.hs from:
module Main where
import Lib
main :: IO ()
main = someFunc
to
import Graphics.UI.Threepenny
main :: IO ()
main = do
startGUI defaultConfig showMessage
showMessage :: Window -> UI ()
showMessage window = do
getBody window #+ [string "Hello, world!"]
return ()
I enter the command $ stack build.
From here, I notice two things. The first is that I receive the following error:
Building all executables for `threepennydemo' once. After a successful build of all of them, only specified executables will be rebuilt.
threepennydemo> configure (lib + exe)
Configuring threepennydemo-0.1.0.0...
threepennydemo> build (lib + exe)
Preprocessing library for threepennydemo-0.1.0.0..
Building library for threepennydemo-0.1.0.0..
Preprocessing executable 'threepennydemo-exe' for threepennydemo-0.1.0.0..
Building executable 'threepennydemo-exe' for threepennydemo-0.1.0.0..
[1 of 2] Compiling Main
/Users/my_username/threepennydemo/app/Main.hs:1:1: error:
Could not load module ‘Graphics.UI.Threepenny’
It is a member of the hidden package ‘threepenny-gui-0.9.0.0’.
Perhaps you need to add ‘threepenny-gui’ to the build-depends in your .cabal file.
Use -v (or `:set -v` in ghci) to see a list of the files searched for.
|
1 | import Graphics.UI.Threepenny
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-- While building package threepennydemo-0.1.0.0 using:
/Users/my_username/.stack/setup-exe-cache/x86_64-osx/Cabal-simple_mPHDZzAJ_3.0.1.0_ghc-8.8.4 --builddir=.stack-work/dist/x86_64-osx/Cabal-3.0.1.0 build lib:threepennydemo exe:threepennydemo-exe --ghc-options " -fdiagnostics-color=always"
Process exited with code: ExitFailure 1
The second is that my .cabal file, edited as mentioned in 2., has automatically removed the edits I made to the file.
What am I missing in order to be able to use a third party library when setting up a new stack project?
My difficulty as the result of some confusion between stack.yaml and package.yaml. The latter being what generates the threepennydemo.cabal file. Hence, dependencies must also be specified to a package.yaml file. Adding this dependency to the package.yaml allowed $ stack build to complete without issue.

How to turn all pedantic mode for hie in haskell?

Is it possible to somehow pass --pedantic (as in stack build --pedantic) switch to Haskell-ide-engine? I'd like to see more errors in IDE during compile time as I'm very new to the language, for example for non-exhaustive case patterns.
I cannot find any infos on project page apart from this bug https://github.com/haskell/haskell-ide-engine/issues/449 but this does not seem to adress this issue.
So far as I can tell it is not possible to pass compiler or build tool switches in to HIE. HIE automatically determines your compiler flags based on your build tool and does not have an override mechanism.
Instead you should add the appropriate compiler flags to your build file. stack build --pedantic passes the -Wall and -Werror flags, so those are the flags you want to add to your build file. That way the flags will always be used by both stack build and HIE.
package.yaml
If you have a package.yaml file (the default for most Stack projects) then you should add the following lines to the ghc-options section of that file:
- -Wall
- -Werror
Example:
name: project-name
version: 0.1.0.0
github: "githubuser/project-name"
license: BSD3
author: "Author name here"
maintainer: "example#example.com"
copyright: "2020 Author name here"
description: Example
dependencies:
- base >= 4.7 && < 5
ghc-options:
- -Wall
- -Werror
executables:
project-name-exe:
main: Main.hs
source-dirs: app
ghc-options:
- -threaded
- -rtsopts
- -with-rtsopts=-N
package-name.cabal
If you do not have a package.yaml file, then add the following lines to all of the executable and library sections your cabal file:
ghc-options:
-Wall
-Werror
Example:
name: project-name
version: 0.1.0.0
-- synopsis:
-- description:
homepage: https://github.com/githubuser/project-name#readme
license: BSD3
license-file: LICENSE
author: Author name here
maintainer: example#example.com
copyright: 2020 Author name here
category: Web
build-type: Simple
cabal-version: >=1.10
extra-source-files: README.md
executable project-name
hs-source-dirs: src
main-is: Main.hs
default-language: Haskell2010
build-depends: base >= 4.7 && < 5
ghc-options:
-Wall
-Werror
More flags
As a side note, GHC's -Wall does not enable all of the warnings, only most of them. You might want to add these extra warnings:
-Wcompat
-Wincomplete-uni-patterns
-Wincomplete-record-updates
-Wredundant-constraints
-Wpartial-fields
See https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/using-warnings.html for more details.
During development you might want to remove -Werror from your package.yaml or cabal file.

Problem loading module Data.Number.CReal in cabal file

I installed a simple proyect with stack, my stack.yaml looks like:
resolver: lts-14.6
packages:
- .
dependencies:
- base (>=3 && <5)
- numbers
and I have a simple code that only calls a function:
module Main where
import Lib
import Data.Number.CReal
main :: IO ()
main = someFunc
and the error is always the same:
numbers-play-0.1.0.0: unregistering (local file changes: numbers-play.cabal)
numbers-play> configure (lib + exe)
Configuring numbers-play-0.1.0.0...
numbers-play> build (lib + exe)
Preprocessing library for numbers-play-0.1.0.0..
Building library for numbers-play-0.1.0.0..
[1 of 2] Compiling Lib
[2 of 2] Compiling Paths_numbers_play
Preprocessing executable 'numbers-play-exe' for numbers-play-0.1.0.0..
Building executable 'numbers-play-exe' for numbers-play-0.1.0.0..
[1 of 2] Compiling Main [Data.Number.CReal changed]
/home/damian/dev/haskell/numbers-play/app/Main.hs:4:1: error:
Could not load module ‘Data.Number.CReal’
It is a member of the hidden package ‘numbers-3000.2.0.2’.
Perhaps you need to add ‘numbers’ to the build-depends in your .cabal file.
Use -v to see a list of the files searched for.
|
4 | import Data.Number.CReal
| ^^^^^^^^^^^^^^^^^^^^^^^^
My cabal file:
cabal-version: 1.12
-- This file has been generated from package.yaml by hpack version 0.31.2.
--
-- see: https://github.com/sol/hpack
--
-- hash: fb0ed9e8eb8062639f1d6a02a65d857d15b3265158925242287d4a8a885f8381
name: numbers-play
version: 0.1.0.0
description: Please see the README on GitHub at <https://github.com/githubuser/numbers-play#readme>
homepage: https://github.com/githubuser/numbers-play#readme
bug-reports: https://github.com/githubuser/numbers-play/issues
author: Author name here
maintainer: example#example.com
copyright: 2019 Author name here
license: BSD3
license-file: LICENSE
build-type: Simple
extra-source-files:
README.md
ChangeLog.md
source-repository head
type: git
location: https://github.com/githubuser/numbers-play
library
exposed-modules:
Lib
other-modules:
Paths_numbers_play
hs-source-dirs:
src
build-depends:
base >=4.7 && <5
default-language: Haskell2010
executable numbers-play-exe
main-is: Main.hs
other-modules:
Paths_numbers_play
hs-source-dirs:
app
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, numbers-play
default-language: Haskell2010
test-suite numbers-play-test
type: exitcode-stdio-1.0
main-is: Spec.hs
other-modules:
Paths_numbers_play
hs-source-dirs:
test
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, numbers-play
default-language: Haskell2010
How can I import it properly?
The dependencies field, which specifies the numbers dependency, should be in your package.yaml file (which Stack uses to generate the cabal file), and not in stack.yaml (which is for Stack-specific configuration, such as choosing the resolver).

Stack fails to build

I am trying to learn haskell here (don't ask why), and I am starting with a very simple code, that i even copied from github.
So the code is this:
module Example () where
import Network.HTTP
-- Non HTTPS
-- 1. Perform a basic HTTP get request and return the body
get :: String -> IO String
get url = simpleHTTP (getRequest url) >>= getResponseBody
-- 2. Get the response code
getCode :: String -> IO ResponseCode
getCode url = simpleHTTP req >>= getResponseCode
where req = getRequest url
However, when I run stack build I get this:
slack-client-0.1.0.0: build
Preprocessing library slack-client-0.1.0.0...
[2 of 2] Compiling Example ( src\Example.hs, .stack-work\dist\b7fec021\
build\Example.o )
D:\haskell\slack-client\src\Example.hs:3:1: error:
Failed to load interface for `Network.HTTP'
It is a member of the hidden package `HTTP-4000.3.3'.
Perhaps you need to add `HTTP' to the build-depends in your .cabal file.
Use -v to see a list of the files searched for.
-- While building package slack-client-0.1.0.0 using:
C:\Users\Mihai\AppData\Roaming\stack\setup-exe-cache\x86_64-windows\setup-
Simple-Cabal-1.24.0.0-ghc-8.0.1.exe --builddir=.stack-work\dist\b7fec021 build l
ib:slack-client exe:slack-client-exe --ghc-options " -ddump-hi -ddump-to-file"
Process exited with code: ExitFailure 1
This is my .cabal file:
name: slack-client
version: 0.1.0.0
synopsis: Initial project template from stack
description: Please see README.md
homepage: https://github.com/githubuser/slack-client#readme
license: BSD3
license-file: LICENSE
author: Author name here
maintainer: example#example.com
copyright: 2016 Author name here
category: Web
build-type: Simple
-- extra-source-files:
cabal-version: >=1.10
library
hs-source-dirs: src
exposed-modules: Lib
other-modules: Example
build-depends: base >= 4.7 && < 5
default-language: Haskell2010
executable slack-client-exe
hs-source-dirs: app
main-is: Main.hs
other-modules: Example
ghc-options: -threaded -rtsopts -with-rtsopts=-N
build-depends: base
, HTTP
, HTTP-Simple
, slack-client
default-language: Haskell2010
test-suite slack-client-test
type: exitcode-stdio-1.0
hs-source-dirs: test
main-is: Spec.hs
build-depends: base
, HTTP-Simple
, slack-client
ghc-options: -threaded -rtsopts -with-rtsopts=-N
default-language: Haskell2010
source-repository head
type: git
location: https://github.com/githubuser/slack-client
What am i doing wrong?
If you want your `Example module to be a part of executable, add to this section
executable slack-client-exe
hs-source-dirs: app
main-is: Main.hs
this line: other-modules: Example.
If you want it to be a part of the library, change
library
hs-source-dirs: src
exposed-modules: Lib
to
library
hs-source-dirs: src
exposed-modules: Lib, Example
And take a look at cabal documentation.

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