Log if there are multiple local packages with the same ID in a project

Co-authored-by: Hécate Kleidukos <Kleidukos@users.noreply.github.com>

Author: edmundnoble

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

@@ -137,7 +137,7 @@ import Distribution.Client.SetupWrapper
 import Distribution.Client.Store
 import Distribution.Client.Targets (userToPackageConstraint)
 import Distribution.Client.Types
-import Distribution.Client.Utils (concatMapM, incVersion)
+import Distribution.Client.Utils (concatMapM, incVersion, duplicatesBy)
 
 import qualified Distribution.Client.BuildReports.Storage as BuildReports
 import qualified Distribution.Client.IndexUtils as IndexUtils
@@ -451,14 +451,28 @@ rebuildProjectConfig
             createDirectoryIfMissingVerbose verbosity True distDirectory
             createDirectoryIfMissingVerbose verbosity True distProjectCacheDirectory
 
-          fetchAndReadSourcePackages
+          sourcePackages <- fetchAndReadSourcePackages
             verbosity
             distDirLayout
             compiler
             projectConfigShared
             projectConfigBuildOnly
             pkgLocations
 
+          case duplicatesBy (comparing srcpkgPackageId) [ pkg | SpecificSourcePackage pkg <- sourcePackages ] of
+            [] -> return ()
+            duplicateSourcePkgs ->
+              liftIO $ noticeDoc verbosity
+              $ vcat
+                  [ text "cabal project has multiple sources for"
+                    <+> (pretty (srcpkgPackageId (head dupeGroup)) <> text ":")
+                    Disp.$+$ Disp.nest 2 (vcat [pretty (srcpkgSource srcpkg) | srcpkg <- toList dupeGroup ])
+                    Disp.$+$ text "the choice of source that will be used is undefined."
+                  | dupeGroup <- duplicateSourcePkgs
+                  ]
+
+          return sourcePackages
+
       informAboutConfigFiles projectConfig = do
         cwd <- getCurrentDirectory
         let out -- output mode is verbose ('notice') if we build outside the project root

cabal-install/src/Distribution/Client/Types/PackageLocation.hs

@@ -16,8 +16,9 @@ import Network.URI (URI)
 import Distribution.Types.PackageId (PackageId)
 
 import Distribution.Client.Types.Repo
-import Distribution.Client.Types.SourceRepo (SourceRepoMaybe)
+import Distribution.Client.Types.SourceRepo (SourceRepoMaybe, SourceRepositoryPackage(..))
 import Distribution.Solver.Types.SourcePackage (SourcePackage)
+import Distribution.Pretty
 
 type UnresolvedPkgLoc = PackageLocation (Maybe FilePath)
 
@@ -39,6 +40,14 @@ data PackageLocation local
     RemoteSourceRepoPackage SourceRepoMaybe local
   deriving (Show, Functor, Eq, Ord, Generic)
 
+instance Pretty (PackageLocation local) where
+  pretty (LocalUnpackedPackage fp) = showFilePath fp
+  pretty (LocalTarballPackage fp) = showFilePath fp
+  pretty (RemoteTarballPackage uri _) = showToken $ show uri
+  pretty (RepoTarballPackage repo pid _) = pretty pid <> showToken "@" <> pretty (repoName repo)
+  pretty (RemoteSourceRepoPackage sourceRepo _) =
+    pretty (srpType sourceRepo) <+> showToken (srpLocation sourceRepo)
+
 instance Binary local => Binary (PackageLocation local)
 instance Structured local => Structured (PackageLocation local)
 

cabal-testsuite/PackageTests/ProjectDupPkg/cabal.out

@@ -1,14 +0,0 @@
-# checking repl command with a 'cabal.project' and no project options
-# cabal repl
-Resolving dependencies...
-Build profile: -w ghc-<GHCVER> -O1
-In order, the following will be built:
- - pkg-one-0.1 (interactive) (first run)
-Configuring pkg-one-0.1...
-Preprocessing library for pkg-one-0.1...
-# checking repl command with the 'all' target
-# cabal repl
-Build profile: -w ghc-<GHCVER> -O1
-In order, the following will be built:
- - pkg-one-0.1 (interactive) (first run)
-Preprocessing library for pkg-one-0.1...

cabal-testsuite/PackageTests/ProjectDupPkg/cabal.test.hs

@@ -1,25 +1,17 @@
 import Test.Cabal.Prelude
 import Data.List (isInfixOf)
 
-main = cabalTest . recordMode RecordMarked $ do
-  liftIO $ skipIfWindows "I'm seeing extra newlines in the output on Windows"
-  let log = recordHeader . pure
-
-  -- If there is only one package in the project then the target could be inferred.
-  log "checking repl command with a 'cabal.project' and no project options"
-  defaultProject <- cabal' "repl" ["pkg-one"]
-  assertOutputContains "the following will be built" defaultProject
-  assertOutputContains "pkg-one-0.1" defaultProject
-  -- Foo is a module in one of the packages pkg-one-0.1
-  -- assertOutputContains "Compiling Foo" defaultProject
-  assertOutputContains "Compiling Bar" defaultProject
-
-  log "checking repl command with the 'all' target"
-  allTarget <- cabal' "repl" ["all"]
-  assertOutputContains "the following will be built" allTarget
-  assertOutputContains "pkg-one-0.1" allTarget
-  -- Foo is a module in one of the packages pkg-one-0.1
-  -- assertOutputContains "Compiling Foo" allTarget
-  assertOutputContains "Compiling Bar" allTarget
+-- output contains filepaths into /tmp, so we only match parts of the output
+main = cabalTest . recordMode DoNotRecord $ do
+  normal <- cabal' "configure" ["-v1", "pkg-one"]
+  let msg = unlines
+        [ "cabal project has multiple sources for pkg-one-0.1:"
+        , "  .*/pkg-one"
+        , "  .*/pkg-two"
+        , "the choice of source that will be used is undefined."
+        ]
+  assertOutputMatches msg normal
+  quiet <- cabal' "configure" ["-v0", "pkg-one"]
+  assertOutputDoesNotMatch msg quiet
 
   return ()

changelog.d/pr-11487

@@ -0,0 +1,7 @@
+---
+synopsis: Log if there are multiple local packages with the same ID in a project
+packages: [cabal-install]
+prs: 11487
+---
+
+Log duplicate local packages with the same package identifier, so that the user knows that only one will be picked.