only report top-level project config files in the default verbosity

in verbose mode report imported files too

cabal-install-solver/src/Distribution/Solver/Types/ProjectConfigPath.hs

@@ -16,6 +16,7 @@ module Distribution.Solver.Types.ProjectConfigPath
 
     -- * Checks and Normalization
     , isCyclicConfigPath
+    , isTopLevelConfigPath
     , canonicalizeConfigPath
     ) where
 
@@ -138,6 +139,11 @@ nullProjectConfigPath = ProjectConfigPath $ "unused" :| []
 isCyclicConfigPath :: ProjectConfigPath -> Bool
 isCyclicConfigPath (ProjectConfigPath p) = length p /= length (NE.nub p)
 
+-- | Check if the project config path is top-level, meaning it was not included by
+-- some other project config.
+isTopLevelConfigPath :: ProjectConfigPath -> Bool
+isTopLevelConfigPath (ProjectConfigPath p) = NE.length p == 1
+
 -- | Prepends the path of the importee to the importer path.
 consProjectConfigPath :: FilePath -> ProjectConfigPath -> ProjectConfigPath
 consProjectConfigPath p ps = ProjectConfigPath (p <| coerce ps)

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

@@ -37,6 +37,7 @@ module Distribution.Client.ProjectConfig
   , writeProjectLocalFreezeConfig
   , writeProjectConfigFile
   , commandLineFlagsToProjectConfig
+  , onlyTopLevelProvenance
 
     -- * Packages within projects
   , ProjectPackageLocation (..)
@@ -1753,3 +1754,9 @@ checkBadPerPackageCompilerPaths compilerPrograms packagesConfig =
        ] of
     [] -> return ()
     ps -> throwIO (BadPerPackageCompilerPaths ps)
+
+-- | Filter out non-top-level project configs
+onlyTopLevelProvenance :: Set ProjectConfigProvenance -> Set ProjectConfigProvenance
+onlyTopLevelProvenance = Set.filter $ \case
+  Implicit -> False
+  Explicit ps -> isTopLevelConfigPath ps

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

@@ -401,7 +401,7 @@ rebuildProjectConfig
     notice (verboseStderr verbosity) . render . vcat $
       text "Configuration is affected by the following files:"
         : [ text "-" <+> docProjectConfigPath path
-          | Explicit path <- Set.toList $ projectConfigProvenance projectConfig
+          | Explicit path <- Set.toList . (if verbosity >= verbose then id else onlyTopLevelProvenance) $ projectConfigProvenance projectConfig
           ]
 
     return (projectConfig <> cliConfig, localPackages)