From b78bc285726a9f0320b27d156c5fba6f40b338af Mon Sep 17 00:00:00 2001
From: patrick brisbin <pbrisbin@gmail.com>
Date: Mon, 13 Jun 2022 17:12:22 +0000
Subject: [PATCH] Add HLint, tweak Spec.hs (#5)

* Commit forgotten cabal file update

* Add conventional .hlint.yaml

This is the one from megarepo, but with the following tweaks:

- Adjust "within" on the restricted-qualification ignore
- Add an ignore for "Use Just"

* Standardize test executable

For a typical project (library), we use Spec.hs, not Main.hs. We use
Main.hs with a Spec.hs when we need to customize the runner.

Remove --module-name=Main.hs, as that's the default.

* Try newer HLint for glob support

* Move to haskell/actions implementation

https://github.com/haskell/actions/issues/81

* Fixup
---
 .github/workflows/ci.yml       |  6 ++--
 .hlint.yaml                    | 65 ++++++++++++++++++++++++++++++++++
 haskell-library-template.cabal |  3 +-
 package.yaml                   |  2 +-
 tests/Main.hs                  |  1 -
 tests/Spec.hs                  |  1 +
 6 files changed, 71 insertions(+), 7 deletions(-)
 create mode 100644 .hlint.yaml
 delete mode 100644 tests/Main.hs
 create mode 100644 tests/Spec.hs

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d238e62..701140b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -32,8 +32,8 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - uses: rwe/actions-hlint-setup@v1
-      - uses: rwe/actions-hlint-run@v2
+      - uses: actions/checkout@v3
+      - uses: haskell/actions/hlint-setup@v2
+      - uses: haskell/actions/hlint-run@v2
         with:
           fail-on: warning
diff --git a/.hlint.yaml b/.hlint.yaml
new file mode 100644
index 0000000..a26d927
--- /dev/null
+++ b/.hlint.yaml
@@ -0,0 +1,65 @@
+- ignore: {name: "Redundant do", within: spec}
+- ignore: {name: "Eta reduce"}
+- ignore: {name: "Use list comprehension"}
+- ignore: {name: "Reduce duplication"}
+- ignore: {name: "Use fmap"}  # we use classy prelude so this would be in error
+- ignore: {name: "Avoid restricted function", within: "**.Prelude"} # allow "as X"
+- ignore: {name: "Use ."}  # commonly broken or less readable
+- ignore: {name: "Use &&"}  # we like "and" at 3+ elements
+- ignore: {name: "Use ||"}  # we like "or" at 3+ elements
+- ignore: {name: "Use join"}  # this often leads to cryptic code when do notation is easier to read
+- ignore: {name: "Use Just"}  # makes code less readable
+- ignore: {name: "Redundant ^."}  # commonly broken by esqueleto
+
+# Custom Warnings
+- warn: {lhs: mapM, rhs: traverse}
+- warn: {lhs: mapM_, rhs: traverse_}
+- warn: {lhs: forM, rhs: for}
+- warn: {lhs: forM_, rhs: for_}
+- warn: {lhs: return, rhs: pure}
+
+# Specify additional command line arguments
+- arguments:
+  - -XBangPatterns
+  - -XDataKinds
+  - -XDeriveAnyClass
+  - -XDeriveFoldable
+  - -XDeriveFunctor
+  - -XDeriveGeneric
+  - -XDeriveLift
+  - -XDeriveTraversable
+  - -XDerivingStrategies
+  - -XFlexibleContexts
+  - -XFlexibleInstances
+  - -XGADTs
+  - -XGeneralizedNewtypeDeriving
+  - -XLambdaCase
+  - -XMultiParamTypeClasses
+  - -XNoImplicitPrelude
+  - -XNoMonomorphismRestriction
+  - -XOverloadedStrings
+  - -XQuasiQuotes
+  - -XRankNTypes
+  - -XRecordWildCards
+  - -XScopedTypeVariables
+  - -XStandaloneDeriving
+  - -XTypeApplications
+  - -XTypeFamilies
+
+- modules:
+  - {name: [Data.Set], as: Set}
+  - {name: [Data.Map], as: Map}
+  - {name: [Data.HashSet], as: HashSet}
+  - {name: [Data.HashMap.Strict], as: HashMap}
+  - {name: [Data.Text], as: T}
+  - {name: [Data.Text.Encoding], as: T}
+  - {name: [Data.Text.IO], as: T}
+  - {name: [Data.Text.Lazy], as: TL}
+  - {name: [Data.Text.Lazy.Encoding], as: TL}
+  - {name: [Data.Text.IO.Lazy], as: TL}
+  - {name: [Data.ByteString], as: BS}
+  - {name: [Data.ByteString.Lazy], as: BSL}
+  - {name: [Data.ByteString.Char8], as: BS8}
+  - {name: [Data.ByteString.Lazy.Char8], as: BSL8}
+  - {name: [Data.List.NonEmpty], as: NE}
+  - {name: [Data.Sequence], as: Seq}
diff --git a/haskell-library-template.cabal b/haskell-library-template.cabal
index 9aac4aa..2da0109 100644
--- a/haskell-library-template.cabal
+++ b/haskell-library-template.cabal
@@ -64,7 +64,7 @@ library
 
 test-suite spec
   type: exitcode-stdio-1.0
-  main-is: Main.hs
+  main-is: Spec.hs
   other-modules:
       Paths_haskell_library_template
   hs-source-dirs:
@@ -97,7 +97,6 @@ test-suite spec
   ghc-options: -Weverything -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missing-local-signatures -Wno-monomorphism-restriction -Wno-unsafe -Wno-safe -threaded -rtsopts "-with-rtsopts=-N"
   build-depends:
       base <5
-    , haskell-library-template
     , hspec
   if impl(ghc >= 8.10)
     ghc-options: -Wno-missing-safe-haskell-mode -Wno-prepositive-qualified-module
diff --git a/package.yaml b/package.yaml
index 11f0cbd..2480a19 100644
--- a/package.yaml
+++ b/package.yaml
@@ -63,7 +63,7 @@ library:
 
 tests:
   spec:
-    main: Main.hs
+    main: Spec.hs
     source-dirs: tests
     ghc-options: -threaded -rtsopts "-with-rtsopts=-N"
     dependencies:
diff --git a/tests/Main.hs b/tests/Main.hs
deleted file mode 100644
index 1fcc19c..0000000
--- a/tests/Main.hs
+++ /dev/null
@@ -1 +0,0 @@
-{-# OPTIONS_GHC -F -pgmF hspec-discover -optF --module-name=Main -Wno-missing-export-lists #-}
diff --git a/tests/Spec.hs b/tests/Spec.hs
new file mode 100644
index 0000000..8044961
--- /dev/null
+++ b/tests/Spec.hs
@@ -0,0 +1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover -Wno-missing-export-lists #-}