Add a dummy --installdir to T5782Diamond test

cabal-testsuite/PackageTests/Regression/T5782Diamond/cabal.out

@@ -34,9 +34,8 @@ Warning: 'hs-source-dirs: src2' directory does not exist.
 Preprocessing executable 'E' for issue5782-0.1..
 Building executable 'E' for issue5782-0.1..
 Installing executable E in <PATH>
-Warning: The directory <ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/incoming/new-<RAND><ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
-Warning: installdir is not defined. Set it in your cabal config file or use --installdir=<path>. Using default installdir: "<ROOT>/cabal.dist/home/.cabal/bin"
-Symlinking 'E' to '<ROOT>/cabal.dist/home/.cabal/bin/E'
+Warning: The directory <GBLTMPDIR>/ghc-<GHCVER>/incoming/new-<RAND><GBLTMPDIR>/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
+Symlinking 'E' to '<GBLTMPDIR>/E'
 # issue5782 E
 "AAA"
 # cabal v2-install
@@ -75,9 +74,8 @@ Warning: 'hs-source-dirs: src2' directory does not exist.
 Preprocessing executable 'E' for issue5782-0.1..
 Building executable 'E' for issue5782-0.1..
 Installing executable E in <PATH>
-Warning: The directory <ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/incoming/new-<RAND><ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
-Warning: installdir is not defined. Set it in your cabal config file or use --installdir=<path>. Using default installdir: "<ROOT>/cabal.dist/home/.cabal/bin"
-Symlinking 'E' to '<ROOT>/cabal.dist/home/.cabal/bin/E'
+Warning: The directory <GBLTMPDIR>/ghc-<GHCVER>/incoming/new-<RAND><GBLTMPDIR>/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
+Symlinking 'E' to '<GBLTMPDIR>/E'
 # issue5782 E
 "BBB"
 # cabal v2-install
@@ -116,8 +114,7 @@ Warning: 'hs-source-dirs: src2' directory does not exist.
 Preprocessing executable 'E' for issue5782-0.1..
 Building executable 'E' for issue5782-0.1..
 Installing executable E in <PATH>
-Warning: The directory <ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/incoming/new-<RAND><ROOT>/cabal.dist/home/.cabal/store/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
-Warning: installdir is not defined. Set it in your cabal config file or use --installdir=<path>. Using default installdir: "<ROOT>/cabal.dist/home/.cabal/bin"
-Symlinking 'E' to '<ROOT>/cabal.dist/home/.cabal/bin/E'
+Warning: The directory <GBLTMPDIR>/ghc-<GHCVER>/incoming/new-<RAND><GBLTMPDIR>/ghc-<GHCVER>/<PACKAGE>-<HASH>/bin is not in the system search path.
+Symlinking 'E' to '<GBLTMPDIR>/E'
 # issue5782 E
 "CCC"

cabal-testsuite/PackageTests/Regression/T5782Diamond/cabal.test.hs

--- when Module.f is changed, with cabal <= 3.2 this non-deterministically fails
+-- When Module.f is changed, with cabal <= 3.2 this non-deterministically fails
 -- to compile and, if it doesn't fail, it also non-deterministically gives
 -- a wrong answer (ignoring the change to Module.f in the output, despite
 -- recompiling, so probably the wrong library is linked in); when running
@@ -6,27 +6,30 @@
 -- the error, often two are enough, even with cabal 3.2, even to get
 -- compilation error
 --   "Ambiguous module name `Module': it was found in multiple packages: issue5782-0.1 issue5782-0.1"
--- not only the wrong result from exe run
+-- not only the wrong result from exe run.
+--
+-- The dummy "--installdir=." is needed for cabal <= 3.2
+-- and also to match cabal output on different OSes
+-- (default installdir is different on various OSes).
 
 import Test.Cabal.Prelude
-main = cabalTest $
+main = withShorterPathForNewBuildStore $ \storeDir ->
+  cabalTest $
     withSourceCopy . withDelay $ do
         writeSourceFile "issue5782/src/Module.hs" "module Module where\nf = \"AAA\""
-        cabal "v2-install" ["--overwrite-policy=always", "issue5782"]
-        -- this is needed for cabal 3.2 to fail for the right reason:
-        -- cabal "v2-install" ["--installdir=.", "--overwrite-policy=always", "issue5782"]
+        cabalG ["--store-dir=" ++ storeDir, "--installdir=" ++ storeDir, "--overwrite-policy=always"] "v2-install" ["issue5782"]
         withPlan $
             runPlanExe' "issue5782" "E" []
                 >>= assertOutputContains "AAA"
         delay
         writeSourceFile "issue5782/src/Module.hs" "module Module where\nf = \"BBB\""
-        cabal "v2-install" ["--overwrite-policy=always", "issue5782"]
+        cabalG ["--store-dir=" ++ storeDir, "--installdir=" ++ storeDir, "--overwrite-policy=always"] "v2-install" ["issue5782"]
         withPlan $
             runPlanExe' "issue5782" "E" []
                 >>= assertOutputContains "BBB"
         writeSourceFile "issue5782/src/Module.hs" "module Module where\nf = \"CCC\""
         delay  -- different spot to try another scenario
-        cabal "v2-install" ["--overwrite-policy=always", "issue5782"]
+        cabalG ["--store-dir=" ++ storeDir, "--installdir=" ++ storeDir, "--overwrite-policy=always"] "v2-install" ["issue5782"]
         withPlan $
             runPlanExe' "issue5782" "E" []
                 >>= assertOutputContains "CCC"