Merge pull request #6051 from commercialhaskell/fix6050

Fix #6050 Drop Cabal versions before 1.22.

Author: mpilgrem

ChangeLog.md

@@ -10,6 +10,8 @@ Major changes:
 
 Behavior changes:
 
+* Drop support for `Cabal` versions before 1.22 and, consequently, GHC versions
+  before 7.10.
 * `stack ghci` and `stack repl` now take into account the values of
   `default-language` keys in Cabal files, like they take into account the values
   of `default-extensions` keys.

doc/maintainers/stack_errors.md

@@ -5,7 +5,7 @@
 In connection with considering Stack's support of the
 [Haskell Error Index](https://errors.haskell.org/) initiative, this page seeks
 to take stock of the errors that Stack itself can raise, by reference to the
-`master` branch of the Stack repository. Last updated: 2023-01-21.
+`master` branch of the Stack repository. Last updated: 2023-02-02.
 
 *   `Main.main`: catches exceptions from action `commandLineHandler`.
 
@@ -60,11 +60,10 @@ to take stock of the errors that Stack itself can raise, by reference to the
         [S-1711] | CannotApplySelector Value [Text]
         ~~~
 
-    -   `Stack.Build.CabalVersionException`
+    -   `Stack.Build.CabalVersionPrettyException`
 
         ~~~haskell
-        [S-8503] = AllowNewerNotSupported Version
-        [S-5973] | CabalVersionNotSupported Version
+        [S-5973] = CabalVersionNotSupported Version
         ~~~
 
     -   `Stack.Build.ConstructPlan.NotOnlyLocal`

src/Stack/Build.hs

@@ -11,7 +11,6 @@ module Stack.Build
   , mkBaseConfigOpts
   , queryBuildInfo
   , splitObjsWarning
-  , CabalVersionException (..)
   ) where
 
 import           Data.Aeson ( Value (Object, Array), (.=), object )
@@ -62,27 +61,26 @@ import           Stack.Types.SourceMap
                    , SourceMap (..), Target (..) )
 import           System.Terminal ( fixCodePage )
 
-data CabalVersionException
-  = AllowNewerNotSupported Version
-  | CabalVersionNotSupported Version
+newtype CabalVersionPrettyException
+  = CabalVersionNotSupported Version
   deriving (Show, Typeable)
 
-instance Exception CabalVersionException where
-  displayException (AllowNewerNotSupported cabalVer) = concat
-    [ "Error: [S-8503]\n"
-    , "'--allow-newer' requires Cabal version 1.22 or greater, but "
-    , "version "
-    , versionString cabalVer
-    , " was found."
-    ]
-  displayException (CabalVersionNotSupported cabalVer) = concat
-    [ "Error: [S-5973]\n"
-    , "Stack no longer supports Cabal versions before 1.19.2, "
-    , "but version "
-    , versionString cabalVer
-    , " was found. To fix this, consider updating the resolver to lts-3.0 "
-    , "or later or to nightly-2015-05-05 or later."
-    ]
+instance Pretty CabalVersionPrettyException where
+  pretty (CabalVersionNotSupported cabalVer) =
+    "[S-5973]"
+    <> line
+    <> fillSep
+         [ flow "Stack does not support Cabal versions before 1.22, but \
+                \version"
+         , fromString $ versionString cabalVer
+         , flow "was found. To fix this, consider updating the snapshot to"
+         , style Shell "lts-3.0"
+         , flow "or later or to"
+         , style Shell "nightly-2015-05-05"
+         , flow "or later."
+         ]
+
+instance Exception CabalVersionPrettyException
 
 data QueryException
   = SelectorNotFound [Text]
@@ -193,17 +191,9 @@ justLocals =
 
 checkCabalVersion :: HasEnvConfig env => RIO env ()
 checkCabalVersion = do
-  allowNewer <- view $ configL.to configAllowNewer
   cabalVer <- view cabalVersionL
-  -- https://github.com/haskell/cabal/issues/2023
-  when (allowNewer && cabalVer < mkVersion [1, 22]) $ throwM $
-    AllowNewerNotSupported cabalVer
-  -- Since --exact-configuration is always passed, some old cabal
-  -- versions can no longer be used. See the following link for why
-  -- it's 1.19.2:
-  -- https://github.com/haskell/cabal/blob/580fe6b6bf4e1648b2f66c1cb9da9f1f1378492c/cabal-install/Distribution/Client/Setup.hs#L592
-  when (cabalVer < mkVersion [1, 19, 2]) $ throwM $
-    CabalVersionNotSupported cabalVer
+  when (cabalVer < mkVersion [1, 22]) $
+    prettyThrowM $ CabalVersionNotSupported cabalVer
 
 -- | See https://github.com/commercialhaskell/stack/issues/1198.
 warnIfExecutablesWithSameNameCouldBeOverwritten ::

src/Stack/Types/Build.hs

@@ -82,8 +82,8 @@ import           Stack.Types.Config
                    ( BenchmarkOpts (..), BuildOpts (..), BuildOptsCLI
                    , BuildSubset (..), Config (..), DumpPackage, EnvConfig
                    , FileWatchOpts (..), GHCVariant, HasConfig (..)
-                   , TestOpts (..), actualCompilerVersionL, cabalVersionL
-                   , defaultBuildOpts, ghcVariantSuffix
+                   , TestOpts (..), actualCompilerVersionL, defaultBuildOpts
+                   , ghcVariantSuffix
                    )
 import           Stack.Types.GhcPkgId ( GhcPkgId, ghcPkgIdString )
 import           Stack.Types.NamedComponent
@@ -1136,13 +1136,10 @@ configureOptsNoDir :: EnvConfig
                    -> [String]
 configureOptsNoDir econfig bco deps isLocal package = concat
   [ depOptions
-  , ["--enable-library-profiling" | boptsLibProfile bopts || boptsExeProfile bopts]
-  -- Cabal < 1.21.1 does not support --enable-profiling, use
-  -- --enable-executable-profiling instead
-  , let profFlag =  "--enable-"
-                 <> concat ["executable-" | not newerCabal]
-                 <> "profiling"
-    in  [ profFlag | boptsExeProfile bopts && isLocal]
+  , [ "--enable-library-profiling"
+    | boptsLibProfile bopts || boptsExeProfile bopts
+    ]
+  , ["--enable-profiling" | boptsExeProfile bopts && isLocal]
   , ["--enable-split-objs" | boptsSplitObjs bopts]
   , [ "--disable-library-stripping"
     | not $ boptsLibStrip bopts || boptsExeStrip bopts
@@ -1206,32 +1203,19 @@ configureOptsNoDir econfig bco deps isLocal package = concat
   config = view configL econfig
   bopts = bcoBuildOpts bco
 
-  newerCabal = view cabalVersionL econfig >= C.mkVersion [1, 22]
-
   -- Unioning atop defaults is needed so that all flags are specified with
   -- --exact-configuration.
   flags = packageFlags package `Map.union` packageDefaultFlags package
 
   depOptions = map (uncurry toDepOption) $ Map.toList deps
-   where
-    toDepOption = if newerCabal then toDepOption1_22 else toDepOption1_18
 
-  toDepOption1_22 (PackageIdentifier name _) gid = concat
+  toDepOption (PackageIdentifier name _) gid = concat
     [ "--dependency="
     , packageNameString name
     , "="
     , ghcPkgIdString gid
     ]
 
-  toDepOption1_18 ident _gid = concat
-    [ "--constraint="
-    , packageNameString name
-    , "=="
-    , versionString version'
-    ]
-   where
-    PackageIdentifier name version' = ident
-
 -- | Get set of wanted package names from locals.
 wantedLocalPackages :: [LocalPackage] -> Set PackageName
 wantedLocalPackages =