Support for weeder step

cabal.haskell-ci

@@ -36,6 +36,11 @@ benchmarks: True
 -- Build haddocks. Accepts booleans or version range.
 haddock: True
 
+-- Run weeder. Accepts booleans or version range.
+-- Expects 'weeder.toml' to live at the repository root,
+-- and the '.hie/' directory to be generated in the repository root.
+weeder: True
+
 -- Run cabal check
 -- cabal-check: True
 

src/HaskellCI/Auxiliary.hs

@@ -49,6 +49,7 @@ data Auxiliary = Auxiliary
     , anyJobUsesPreviewGHC    :: Bool
     , runHaddock              :: Bool
     , haddockFlags            :: String
+    , runWeeder               :: Bool
     }
 
 auxiliary :: Config -> Project URI Void Package -> JobVersions -> Auxiliary
@@ -84,6 +85,8 @@ auxiliary Config {..} prj JobVersions {..} = Auxiliary {..}
         ComponentsAll  -> " --haddock-all"
         ComponentsLibs -> ""
 
+    runWeeder = not (equivVersionRanges C.noVersion cfgWeeder)
+
     extraCabalProjectFields :: FilePath -> [C.PrettyField ()]
     extraCabalProjectFields rootdir = buildList $ do
         -- generate package fields for URI packages.

src/HaskellCI/Config/Grammar.hs

@@ -90,6 +90,8 @@ configGrammar = Config
         ^^^ metahelp "RANGE" "Haddock step"
     <*> optionalFieldDef   "haddock-components"                                             (field @"cfgHaddockComponents") defaultConfig
         ^^^ metahelp "all|libs" "Haddock components"
+    <*> rangeField           "weeder"                                                       (field @"cfgWeeder") defaultConfig
+        ^^^ metahelp "RANGE" "Weeder step"
     <*> rangeField           "no-tests-no-benchmarks"                                       (field @"cfgNoTestsNoBench") defaultConfig
         ^^^ metahelp "RANGE" "Build without tests and benchmarks"
     <*> rangeField            "unconstrained"                                               (field @"cfgUnconstrainted") defaultConfig

src/HaskellCI/Config/Initial.hs

@@ -37,6 +37,7 @@ initialConfig = Config
     , cfgBenchmarks          = anyVersion
     , cfgHaddock             = anyVersion
     , cfgHaddockComponents   = ComponentsAll
+    , cfgWeeder              = noVersion
     , cfgNoTestsNoBench      = anyVersion
     , cfgUnconstrainted      = anyVersion
     , cfgHeadHackage         = defaultHeadHackage

src/HaskellCI/Config/Type.hs

@@ -42,6 +42,7 @@ data Config = Config
     , cfgBenchmarks          :: !VersionRange
     , cfgHaddock             :: !VersionRange
     , cfgHaddockComponents   :: !Components
+    , cfgWeeder              :: !VersionRange
     , cfgNoTestsNoBench      :: !VersionRange
     , cfgUnconstrainted      :: !VersionRange
     , cfgHeadHackage         :: !VersionRange

src/HaskellCI/GitHub.hs

@@ -536,6 +536,15 @@ makeGitHub _argv config@Config {..} gitconfig prj jobs@JobVersions {..} = do
             -- disable-documentation disables docs in deps: https://github.com/haskell/cabal/issues/7462
             sh_if range $ "$CABAL v2-haddock --disable-documentation" ++ haddockFlags ++ " $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all"
 
+        when runWeeder $
+            let range = RangeGHC /\ Range cfgWeeder in
+            let ifCond = ghCompilerVersionArithPredicate allVersions range in
+            for_ pkgs $ \Pkg{pkgName} -> do
+                githubUsesIf "weeder" "freckle/weeder-action@v2" ifCond $ buildList $ do
+                    item ("ghc-version", ghWrapExpr "matrix.compilerVersion")
+                    item ("weeder-arguments", "--config $GITHUB_WORKSPACE/source/weeder.toml")
+                    item ("working-directory", ghWrapExpr $ ghEnvContext $ pkgNameDirVariable' pkgName)
+
         -- unconstrained build
         unless (equivVersionRanges C.noVersion cfgUnconstrainted) $ githubRun "unconstrained build" $ do
             let range = Range cfgUnconstrainted
@@ -855,3 +864,13 @@ parseGitHubRepo t =
 -- runners support.
 ghcRunsOnVer :: String
 ghcRunsOnVer = "ubuntu-20.04"
+
+ghWrapExpr :: String -> String
+ghWrapExpr expr = "${{ " ++ expr ++ " }}"
+
+ghEnvContext :: String -> String
+ghEnvContext = ("env." ++)
+
+ghCompilerVersionArithPredicate :: Set CompilerVersion -> CompilerRange -> String
+ghCompilerVersionArithPredicate = compilerVersionPredicateImpl $
+    freeToArith $ ExprConfig ghWrapExpr ghEnvContext

src/HaskellCI/ShVersionRange.hs

@@ -1,6 +1,9 @@
 module HaskellCI.ShVersionRange (
     compilerVersionPredicate,
     compilerVersionArithPredicate,
+    compilerVersionPredicateImpl,
+    freeToArith,
+    ExprConfig (..),
     roundDown,
 ) where
 
@@ -21,11 +24,11 @@ import HaskellCI.Compiler
 -- >>> import qualified Distribution.Version as C
 
 compilerVersionPredicate :: Set CompilerVersion -> CompilerRange -> String
-compilerVersionPredicate = compilerVersionPredicateImpl (toTest . freeToArith) where
+compilerVersionPredicate = compilerVersionPredicateImpl (toTest . shFreeToArith) where
     toTest expr = "[ " ++ expr ++ " -ne 0 ]"
 
 compilerVersionArithPredicate :: Set CompilerVersion -> CompilerRange -> String
-compilerVersionArithPredicate = compilerVersionPredicateImpl freeToArith
+compilerVersionArithPredicate = compilerVersionPredicateImpl shFreeToArith
 
 compilerVersionPredicateImpl
     :: (Free String -> String)
@@ -197,14 +200,25 @@ roundDown = go S.empty . S.toList where
 -- Arithmetic expression
 -------------------------------------------------------------------------------
 
-freeToArith :: Free String -> String
-freeToArith z
+shWrapExpr :: String -> String
+shWrapExpr expr = "$((" ++ expr ++ "))"
+
+shFreeToArith :: Free String -> String
+shFreeToArith = freeToArith $ ExprConfig shWrapExpr id
+
+data ExprConfig = ExprConfig {
+      _exprWrap :: String -> String
+    , _varWrap :: String -> String
+    }
+
+freeToArith :: ExprConfig -> Free String -> String
+freeToArith (ExprConfig exprWrap varWrap) z
     | z == top    = "1"
     | z == bottom = "0"
-    | otherwise   = "$((" ++ go 0 z ++ "))"
+    | otherwise   = exprWrap $ go 0 z
   where
     go :: Int -> Free String -> String
-    go _ (Var x)  = x
+    go _ (Var x)  = varWrap x
     go _ F.Bottom = "1"
     go _ F.Top    = "0"