Avoid using duplicate global config not adding it in the dummy project context

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

@@ -197,8 +197,8 @@ replCommand = Client.installCommand {
 replAction :: NixStyleFlags (ReplOptions, EnvFlags) -> [String] -> GlobalFlags -> IO ()
 replAction flags@NixStyleFlags { extraFlags = (replFlags, envFlags), ..} targetStrings globalFlags = do
     let
-      with           = withProject    cliConfig             verbosity targetStrings
-      without config = withoutProject (config <> cliConfig) verbosity targetStrings
+      with                 = withProject    cliConfig                   verbosity targetStrings
+      without globalConfig = withoutProject (globalConfig <> cliConfig) verbosity targetStrings
 
     (baseCtx, targetSelectors, finalizer, replType) <-
       withProjectOrGlobalConfig verbosity ignoreProject globalConfigFlag with without

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

@@ -164,9 +164,9 @@ runAction flags@NixStyleFlags {..} targetStrings globalFlags = do
     let
       with =
         establishProjectBaseContext verbosity cliConfig OtherCommand
-      without config = do
-        distDirLayout <- establishDummyDistDirLayout verbosity (config <> cliConfig) tmpDir
-        establishDummyProjectBaseContext verbosity (config <> cliConfig) distDirLayout [] OtherCommand
+      without globalConfig = do
+        distDirLayout <- establishDummyDistDirLayout verbosity (globalConfig <> cliConfig) tmpDir
+        establishDummyProjectBaseContext verbosity (globalConfig <> cliConfig) distDirLayout [] OtherCommand
 
     baseCtx <- withProjectOrGlobalConfig verbosity ignoreProject globalConfigFlag with without
 

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

@@ -113,7 +113,6 @@ import qualified Distribution.Client.ProjectPlanning as ProjectPlanning
 import           Distribution.Client.ProjectPlanning.Types
 import           Distribution.Client.ProjectBuilding
 import           Distribution.Client.ProjectPlanOutput
-import           Distribution.Client.RebuildMonad ( runRebuild )
 
 import           Distribution.Client.TargetProblem
                    ( TargetProblem (..) )
@@ -1305,21 +1304,16 @@ data BuildFailurePresentation =
 establishDummyProjectBaseContext
   :: Verbosity
   -> ProjectConfig
+     -- ^ Project configuration including the global config if needed
   -> DistDirLayout
      -- ^ Where to put the dist directory
   -> [PackageSpecifier UnresolvedSourcePackage]
      -- ^ The packages to be included in the project
   -> CurrentCommand
   -> IO ProjectBaseContext
-establishDummyProjectBaseContext verbosity cliConfig distDirLayout localPackages currentCommand = do
+establishDummyProjectBaseContext verbosity projectConfig distDirLayout localPackages currentCommand = do
     cabalDir <- getCabalDir
 
-    globalConfig <- runRebuild ""
-                  $ readGlobalConfig verbosity
-                  $ projectConfigConfigFile
-                  $ projectConfigShared cliConfig
-    let projectConfig = globalConfig <> cliConfig
-
     let ProjectConfigBuildOnly {
           projectConfigLogsDir
         } = projectConfigBuildOnly projectConfig

cabal-testsuite/PackageTests/Regression/T6906/cabal.test.hs

@@ -1,9 +1,9 @@
 import Test.Cabal.Prelude
 
 main = cabalTest $ do
-   res <- cabalG' ["--config=cabal.config"] "v2-install" ["-v3"]
+   res <- recordMode DoNotRecord $ cabalG' ["--config=cabal.config"] "v2-install" ["-v3"]
    assertOutputContains "creating file with the inputs used to compute the package hash:" res
    assertOutputContains "extra-lib-dirs: bar" res
-   expectBroken 6906 $ assertOutputDoesNotContain "extra-lib-dirs: bar bar" res
+   assertOutputDoesNotContain "extra-lib-dirs: bar bar" res
    assertOutputContains "extra-include-dirs: foo" res
-   expectBroken 6906 $ assertOutputDoesNotContain "extra-include-dirs: foo foo" res
+   assertOutputDoesNotContain "extra-include-dirs: foo foo" res

changelog.d/issue-6906

@@ -0,0 +1,4 @@
+synopsis: cabal v2 commands (install, repl, run) uses duplicate global config and rebuilds libs twice in the store
+packages: cabal-install
+issues: #6907
+prs: #7753 #7759