pretty-print run targets on failure

Cabal-syntax/src/Distribution/Types/ComponentName.hs

@@ -1,9 +1,11 @@
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE PatternSynonyms #-}
 
 module Distribution.Types.ComponentName (
-  ComponentName(..),
+  ComponentName(.., CFLibName, CExeName, CTestName, CBenchName),
   showComponentName,
+  componentNameRaw,
   componentNameStanza,
   componentNameString,
   ) where
@@ -21,12 +23,32 @@ import qualified Distribution.Compat.CharParsing as P
 
 -- Libraries live in a separate namespace, so must distinguish
 data ComponentName = CLibName   LibraryName
-                   | CFLibName  UnqualComponentName
-                   | CExeName   UnqualComponentName
-                   | CTestName  UnqualComponentName
-                   | CBenchName UnqualComponentName
+                   | CNotLibName NotLibComponentName
                    deriving (Eq, Generic, Ord, Read, Show, Typeable)
 
+data NotLibComponentName
+                   = CNLFLibName  { toCompName :: UnqualComponentName }
+                   | CNLExeName   { toCompName :: UnqualComponentName }
+                   | CNLTestName  { toCompName :: UnqualComponentName }
+                   | CNLBenchName { toCompName :: UnqualComponentName }
+                   deriving (Eq, Generic, Ord, Read, Show, Typeable)
+
+pattern CFLibName :: UnqualComponentName -> ComponentName
+pattern CFLibName  n = CNotLibName (CNLFLibName  n)
+
+pattern CExeName :: UnqualComponentName -> ComponentName
+pattern CExeName   n = CNotLibName (CNLExeName   n)
+
+pattern CTestName :: UnqualComponentName -> ComponentName
+pattern CTestName  n = CNotLibName (CNLTestName  n)
+
+pattern CBenchName :: UnqualComponentName -> ComponentName
+pattern CBenchName n = CNotLibName (CNLBenchName n)
+{-# COMPLETE CLibName, CFLibName, CExeName, CTestName, CBenchName #-}
+
+instance Binary NotLibComponentName
+instance Structured NotLibComponentName
+
 instance Binary ComponentName
 instance Structured ComponentName
 
@@ -59,6 +81,10 @@ showComponentName (CExeName   name) = "executable '" ++ prettyShow name ++ "'"
 showComponentName (CTestName  name) = "test suite '" ++ prettyShow name ++ "'"
 showComponentName (CBenchName name) = "benchmark '" ++ prettyShow name ++ "'"
 
+componentNameRaw :: ComponentName -> String
+componentNameRaw l@(CLibName  _) = showComponentName l
+componentNameRaw (CNotLibName x) = prettyShow $ toCompName x
+
 componentNameStanza :: ComponentName -> String
 componentNameStanza (CLibName lib)    = libraryNameStanza lib
 componentNameStanza (CFLibName  name) = "foreign-library " ++ prettyShow name
@@ -71,8 +97,5 @@ componentNameStanza (CBenchName name) = "benchmark " ++ prettyShow name
 -- @Nothing@ if the 'ComponentName' was for the public
 -- library.
 componentNameString :: ComponentName -> Maybe UnqualComponentName
-componentNameString (CLibName lib) = libraryNameString lib
-componentNameString (CFLibName  n) = Just n
-componentNameString (CExeName   n) = Just n
-componentNameString (CTestName  n) = Just n
-componentNameString (CBenchName n) = Just n
+componentNameString (CLibName  lib) = libraryNameString lib
+componentNameString (CNotLibName x) = Just $ toCompName x

cabal-install/src/Distribution/Client/CmdErrorMessages.hs

@@ -72,6 +72,13 @@ renderListCommaAnd [x]    = x
 renderListCommaAnd [x,x'] = x ++ " and " ++ x'
 renderListCommaAnd (x:xs) = x ++ ", " ++ renderListCommaAnd xs
 
+renderListTabular :: [String] -> String
+renderListTabular = ("\n"++) . unlines . map ("| * "++)
+
+renderListPretty :: [String] -> String
+renderListPretty xs = if length xs > 5 then renderListTabular xs
+                                       else renderListCommaAnd xs
+
 -- | Render a list of things in the style @blah blah; this that; and the other@
 renderListSemiAnd :: [String] -> String
 renderListSemiAnd []     = ""

cabal-install/src/Distribution/Client/CmdRun.hs

@@ -27,7 +27,8 @@ import Distribution.Client.CmdErrorMessages
          ( renderTargetSelector, showTargetSelector,
            renderTargetProblem,
            renderTargetProblemNoTargets, plural, targetSelectorPluralPkgs,
-           targetSelectorFilter, renderListCommaAnd )
+           targetSelectorFilter, renderListCommaAnd,
+           renderListPretty )
 import Distribution.Client.TargetProblem
          ( TargetProblem (..) )
 
@@ -42,11 +43,11 @@ import Distribution.Simple.Flag
 import Distribution.Simple.Command
          ( CommandUI(..), usageAlternatives )
 import Distribution.Types.ComponentName
-         ( showComponentName )
+         ( componentNameRaw )
 import Distribution.Verbosity
          ( normal, silent )
 import Distribution.Simple.Utils
-         ( wrapText, die', info, notice )
+         ( wrapText, die', info, notice, safeHead )
 import Distribution.Client.ProjectPlanning
          ( ElaboratedConfiguredPackage(..)
          , ElaboratedInstallPlan, binDirectoryFor )
@@ -64,6 +65,7 @@ import Distribution.Types.UnitId
 import Distribution.Client.ScriptUtils
          ( AcceptNoTargets(..), withContextAndSelectors, updateContextAndWriteProjectFile, TargetContext(..) )
 
+import Data.List (group)
 import qualified Data.Set as Set
 import System.Directory
          ( doesFileExist )
@@ -424,14 +426,13 @@ renderRunProblem :: RunProblem -> String
 renderRunProblem (TargetProblemMatchesMultiple targetSelector targets) =
     "The run command is for running a single executable at once. The target '"
  ++ showTargetSelector targetSelector ++ "' refers to "
- ++ renderTargetSelector targetSelector ++ " which includes "
- ++ renderListCommaAnd ( ("the "++) <$>
-                         showComponentName <$>
-                         availableTargetComponentName <$>
-                         foldMap
-                           (\kind -> filterTargetsKind kind targets)
-                           [ExeKind, TestKind, BenchKind] )
- ++ "."
+ ++ renderTargetSelector targetSelector ++ " which includes \n"
+ ++ unlines ((\(label, xs) -> "- " ++ label ++ ": " ++ renderListPretty xs)
+    <$> (zip ["executables", "test-suites", "benchmarks"]
+     $  filter (not . null) . map removeDuplicates
+     $  map (componentNameRaw . availableTargetComponentName)
+    <$> (flip filterTargetsKind $ targets) <$> [ExeKind, TestKind, BenchKind] ))
+    where removeDuplicates = catMaybes . map safeHead . group . sort
 
 renderRunProblem (TargetProblemMultipleTargets selectorMap) =
     "The run command is for running a single executable at once. The targets "

cabal-testsuite/PackageTests/NewBuild/CmdRun/MultipleExes/cabal.out

@@ -16,6 +16,8 @@ Building executable 'bar' for MultipleExes-1.0..
 # cabal v2-run
 Up to date
 # cabal v2-run
-Error: cabal: The run command is for running a single executable at once. The target '' refers to the package MultipleExes-1.0 which includes the executable 'foo' and the executable 'bar'.
+Error: cabal: The run command is for running a single executable at once. The target '' refers to the package MultipleExes-1.0 which includes 
+- executables: bar and foo
 # cabal v2-run
-Error: cabal: The run command is for running a single executable at once. The target 'MultipleExes' refers to the package MultipleExes-1.0 which includes the executable 'foo' and the executable 'bar'.
+Error: cabal: The run command is for running a single executable at once. The target 'MultipleExes' refers to the package MultipleExes-1.0 which includes 
+- executables: bar and foo

cabal-testsuite/PackageTests/NewBuild/CmdRun/MultiplePackages/cabal.out

@@ -25,7 +25,8 @@ Building executable 'foo-exe' for bar-1.0..
 # cabal v2-run
 Error: cabal: No targets given and there is no package in the current directory. Specify packages or components by name or location. See 'cabal build --help' for more details on target options.
 # cabal v2-run
-Error: cabal: The run command is for running a single executable at once. The target 'bar' refers to the package bar-1.0 which includes the executable 'foo-exe' and the executable 'bar-exe'.
+Error: cabal: The run command is for running a single executable at once. The target 'bar' refers to the package bar-1.0 which includes 
+- executables: bar-exe and foo-exe
 # cabal v2-run
 Error: cabal: Ambiguous target 'foo-exe'. It could be:
     bar:foo-exe (component)

changelog.d/issue-8189

@@ -0,0 +1,11 @@
+synopsis: Pretty-print run targets on failure
+packages: cabal-install
+prs: #8234
+issues: #8189
+
+description: {
+
+- Targets of the `run` command are pretty-printed when failing due to multiple targets. 
+- Duplicate targets are removed in the output.
+
+}