Cabal: Reexport all of Cabal-syntax

To preserve compatibility for downstream users Cabal will reexport all
of Cabal-syntax for the time being. In the future we may deprecate these
reexports.

This requires that we bump the cabal-version of Cabal.cabal to 1.22 and
drops support for GHC < 7.10.

Closes #7974.

Author: bgamari

Cabal/Cabal.cabal

@@ -1,4 +1,4 @@
-cabal-version: >=1.10
+cabal-version: >=1.22
 name:          Cabal
 version:       3.7.0.0
 copyright:     2003-2021, Cabal Development Team (see AUTHORS file)
@@ -164,6 +164,148 @@ library
     Distribution.Verbosity
     Distribution.Verbosity.Internal
 
+  -- We reexport all of Cabal-syntax to aid in compatibility for downstream
+  -- users. In the future we may opt to deprecate some or all of these exports.
+  -- See haskell/Cabal#7974.
+  reexported-modules:
+    Distribution.Backpack,
+    Distribution.CabalSpecVersion,
+    Distribution.Compat.Binary,
+    Distribution.Compat.CharParsing,
+    Distribution.Compat.DList,
+    Distribution.Compat.Exception,
+    Distribution.Compat.Graph,
+    Distribution.Compat.Lens,
+    Distribution.Compat.MonadFail,
+    Distribution.Compat.Newtype,
+    Distribution.Compat.NonEmptySet,
+    Distribution.Compat.Parsing,
+    Distribution.Compat.Prelude,
+    Distribution.Compat.Semigroup,
+    Distribution.Compat.Typeable,
+    Distribution.Compiler,
+    Distribution.FieldGrammar,
+    Distribution.FieldGrammar.Class,
+    Distribution.FieldGrammar.FieldDescrs,
+    Distribution.FieldGrammar.Newtypes,
+    Distribution.FieldGrammar.Parsec,
+    Distribution.FieldGrammar.Pretty,
+    Distribution.Fields,
+    Distribution.Fields.ConfVar,
+    Distribution.Fields.Field,
+    Distribution.Fields.Lexer,
+    Distribution.Fields.LexerMonad,
+    Distribution.Fields.ParseResult,
+    Distribution.Fields.Parser,
+    Distribution.Fields.Pretty,
+    Distribution.InstalledPackageInfo,
+    Distribution.License,
+    Distribution.ModuleName,
+    Distribution.Package,
+    Distribution.PackageDescription,
+    Distribution.PackageDescription.Configuration,
+    Distribution.PackageDescription.FieldGrammar,
+    Distribution.PackageDescription.Parsec,
+    Distribution.PackageDescription.PrettyPrint,
+    Distribution.PackageDescription.Quirks,
+    Distribution.PackageDescription.Utils,
+    Distribution.Parsec,
+    Distribution.Parsec.Error,
+    Distribution.Parsec.FieldLineStream,
+    Distribution.Parsec.Position,
+    Distribution.Parsec.Warning,
+    Distribution.Pretty,
+    Distribution.SPDX,
+    Distribution.SPDX.License,
+    Distribution.SPDX.LicenseExceptionId,
+    Distribution.SPDX.LicenseExpression,
+    Distribution.SPDX.LicenseId,
+    Distribution.SPDX.LicenseListVersion,
+    Distribution.SPDX.LicenseReference,
+    Distribution.System,
+    Distribution.Text,
+    Distribution.Types.AbiDependency,
+    Distribution.Types.AbiHash,
+    Distribution.Types.Benchmark,
+    Distribution.Types.Benchmark.Lens,
+    Distribution.Types.BenchmarkInterface,
+    Distribution.Types.BenchmarkType,
+    Distribution.Types.BuildInfo,
+    Distribution.Types.BuildInfo.Lens,
+    Distribution.Types.BuildType,
+    Distribution.Types.Component,
+    Distribution.Types.ComponentId,
+    Distribution.Types.ComponentName,
+    Distribution.Types.ComponentRequestedSpec,
+    Distribution.Types.CondTree,
+    Distribution.Types.Condition,
+    Distribution.Types.ConfVar,
+    Distribution.Types.Dependency,
+    Distribution.Types.DependencyMap,
+    Distribution.Types.ExeDependency,
+    Distribution.Types.Executable,
+    Distribution.Types.Executable.Lens,
+    Distribution.Types.ExecutableScope,
+    Distribution.Types.ExposedModule,
+    Distribution.Types.Flag,
+    Distribution.Types.ForeignLib,
+    Distribution.Types.ForeignLib.Lens,
+    Distribution.Types.ForeignLibOption,
+    Distribution.Types.ForeignLibType,
+    Distribution.Types.GenericPackageDescription,
+    Distribution.Types.GenericPackageDescription.Lens,
+    Distribution.Types.HookedBuildInfo,
+    Distribution.Types.IncludeRenaming,
+    Distribution.Types.InstalledPackageInfo,
+    Distribution.Types.InstalledPackageInfo.Lens,
+    Distribution.Types.InstalledPackageInfo.FieldGrammar,
+    Distribution.Types.LegacyExeDependency,
+    Distribution.Types.Lens,
+    Distribution.Types.Library,
+    Distribution.Types.Library.Lens,
+    Distribution.Types.LibraryName,
+    Distribution.Types.LibraryVisibility,
+    Distribution.Types.Mixin,
+    Distribution.Types.Module,
+    Distribution.Types.ModuleReexport,
+    Distribution.Types.ModuleRenaming,
+    Distribution.Types.MungedPackageId,
+    Distribution.Types.MungedPackageName,
+    Distribution.Types.PackageDescription,
+    Distribution.Types.PackageDescription.Lens,
+    Distribution.Types.PackageId,
+    Distribution.Types.PackageId.Lens,
+    Distribution.Types.PackageName,
+    Distribution.Types.PackageVersionConstraint,
+    Distribution.Types.PkgconfigDependency,
+    Distribution.Types.PkgconfigName,
+    Distribution.Types.PkgconfigVersion,
+    Distribution.Types.PkgconfigVersionRange,
+    Distribution.Types.SetupBuildInfo,
+    Distribution.Types.SetupBuildInfo.Lens,
+    Distribution.Types.SourceRepo,
+    Distribution.Types.SourceRepo.Lens,
+    Distribution.Types.TestSuite,
+    Distribution.Types.TestSuite.Lens,
+    Distribution.Types.TestSuiteInterface,
+    Distribution.Types.TestType,
+    Distribution.Types.UnitId,
+    Distribution.Types.UnqualComponentName,
+    Distribution.Types.Version,
+    Distribution.Types.VersionInterval,
+    Distribution.Types.VersionInterval.Legacy,
+    Distribution.Types.VersionRange,
+    Distribution.Types.VersionRange.Internal,
+    Distribution.Utils.Base62,
+    Distribution.Utils.Generic,
+    Distribution.Utils.MD5,
+    Distribution.Utils.Path,
+    Distribution.Utils.ShortText,
+    Distribution.Utils.String,
+    Distribution.Utils.Structured,
+    Distribution.Version,
+    Language.Haskell.Extension
+
   -- Parsec parser-related modules
   build-depends:
     -- transformers-0.4.0.0 doesn't have record syntax e.g. for Identity

changelog.d/cabal-syntax

@@ -3,5 +3,8 @@ prs: #7620
 issues: #7559
 
 description {
-- Extract `Cabal-syntax` from `Cabal` to provide the syntax and parsing code for `.cabal` files
+- Extract `Cabal-syntax` from `Cabal` to provide the syntax and parsing code
+  for `.cabal` files. `Cabal` currently reexports all of the modules which were
+  moved to `Cabal-syntax` although these exports may be deprecated in the
+  future.
 }