Move the ExtDependency type to the only module where it's used

Fewer shared types makes the code easier to grok and navigate.

cabal-install/Distribution/Client/Dependency/Types.hs

@@ -13,8 +13,6 @@
 -- Common types for dependency resolution.
 -----------------------------------------------------------------------------
 module Distribution.Client.Dependency.Types (
-    ExtDependency(..),
-
     PreSolver(..),
     Solver(..),
     DependencyResolver,
@@ -48,9 +46,6 @@ import Data.Monoid
 import Distribution.Client.Types
          ( OptionalStanza(..), SourcePackage(..), ConfiguredPackage )
 
-import Distribution.Compat.ReadP
-         ( (<++) )
-
 import qualified Distribution.Compat.ReadP as Parse
          ( pfail, munch1 )
 import Distribution.PackageDescription
@@ -61,7 +56,7 @@ import qualified Distribution.Client.PackageIndex as PackageIndex
          ( PackageIndex )
 import Distribution.Simple.PackageIndex ( InstalledPackageIndex )
 import Distribution.Package
-         ( Dependency, PackageName, InstalledPackageId )
+         ( PackageName )
 import Distribution.Version
          ( VersionRange, simplifyVersionRange )
 import Distribution.Compiler
@@ -76,16 +71,6 @@ import Text.PrettyPrint
 
 import Prelude hiding (fail)
 
--- | Covers source dependencies and installed dependencies in
--- one type.
-data ExtDependency = SourceDependency Dependency
-                   | InstalledDependency InstalledPackageId
-
-instance Text ExtDependency where
-  disp (SourceDependency    dep) = disp dep
-  disp (InstalledDependency dep) = disp dep
-
-  parse = (SourceDependency `fmap` parse) <++ (InstalledDependency `fmap` parse)
 
 -- | All the solvers that can be selected.
 data PreSolver = AlwaysTopDown | AlwaysModular | Choose

cabal-install/Distribution/Client/List.hs

@@ -15,7 +15,8 @@ module Distribution.Client.List (
 
 import Distribution.Package
          ( PackageName(..), Package(..), packageName, packageVersion
-         , Dependency(..), simplifyDependency )
+         , Dependency(..), simplifyDependency
+         , InstalledPackageId )
 import Distribution.ModuleName (ModuleName)
 import Distribution.License (License)
 import qualified Distribution.InstalledPackageInfo as Installed
@@ -44,7 +45,7 @@ import Distribution.Text
 import Distribution.Client.Types
          ( SourcePackage(..), Repo, SourcePackageDb(..) )
 import Distribution.Client.Dependency.Types
-         ( PackageConstraint(..), ExtDependency(..) )
+         ( PackageConstraint(..) )
 import Distribution.Client.Targets
          ( UserTarget, resolveUserTargets, PackageSpecifier(..) )
 import Distribution.Client.Setup
@@ -292,6 +293,11 @@ data PackageDisplayInfo = PackageDisplayInfo {
     haveTarball       :: Bool
   }
 
+-- | Covers source dependencies and installed dependencies in
+-- one type.
+data ExtDependency = SourceDependency Dependency
+                   | InstalledDependency InstalledPackageId
+
 showPackageSummaryInfo :: PackageDisplayInfo -> String
 showPackageSummaryInfo pkginfo =
   renderStyle (style {lineLength = 80, ribbonsPerLine = 1}) $
@@ -344,7 +350,7 @@ showPackageDetailedInfo pkginfo =
    , entry "Source repo"   sourceRepo   orNotSpecified text
    , entry "Executables"   executables  hideIfNull     (commaSep text)
    , entry "Flags"         flags        hideIfNull     (commaSep dispFlag)
-   , entry "Dependencies"  dependencies hideIfNull     (commaSep disp)
+   , entry "Dependencies"  dependencies hideIfNull     (commaSep dispExtDep)
    , entry "Documentation" haddockHtml  showIfInstalled text
    , entry "Cached"        haveTarball  alwaysShow     dispYesNo
    , if not (hasLib pkginfo) then empty else
@@ -378,6 +384,9 @@ showPackageDetailedInfo pkginfo =
     dispYesNo True  = text "Yes"
     dispYesNo False = text "No"
 
+    dispExtDep (SourceDependency    dep) = disp dep
+    dispExtDep (InstalledDependency dep) = disp dep
+
     isInstalled = not (null (installedVersions pkginfo))
     hasExes = length (executables pkginfo) >= 2
     --TODO: exclude non-buildable exes