Modify test file the proper way

Co-authored-by: sheaf <sam.derbyshire@gmail.com>

Author: tdammers

cabal-testsuite/PackageTests/SetupHooks/SetupHooksRecursiveGlob/setup.test.hs

@@ -1,21 +1,8 @@
-import Test.Cabal.Prelude
-
-import Control.Monad.Catch (finally)
-
 main =
   setupTest $ do
-    runSetupTest `finally` cleanup
-  where
-    runSetupTest = do
-        setup "configure" []
-        setup "build" []
-        -- Now modify one file and build again to see if that exact file gets rebuilt
-        env <- getTestEnv
-        liftIO $ do
-          let srcDir = testSourceDir env
-          writeFile (srcDir </> "src/Foo/B.ppExt") "module Foo.B where\nModified text"
-        setup "build" []
-    cleanup = do
-      env <- getTestEnv
-      let srcDir = testSourceDir env
-      liftIO $ writeFile (srcDir </> "src/Foo/B.ppExt") "module Foo.B where\nOriginal text\n"
+    setup "configure" []
+    setup "build" []
+    -- Modify one file in the temp copy (testCurrentDir) and rebuild; only
+    -- the preprocessor rule for Foo.B should re-run, not the one for A.
+    writeSourceFile "src/Foo/B.ppExt" "module Foo.B where\nModified text"
+    setup "build" []