Shrinking with resources is broken

[NorfairKing]

This Spec shows "Invariant of resources not maintained during shrinking" after 21 tests and 1 shrinks:

  modifyMaxSize (const 30) $
    describe "Shrinking" $ do
      var <- liftIO $ newTVarIO False
      let withTrue func = do
            atomically $ writeTVar var True
            r <- func
            atomically $ writeTVar var False
            pure r
      around_ withTrue $
        it "maintains resource invariants correctly" $
          forAllShrink (sized $ \n -> pure n) shrink $ \i -> do
            b <- readTVarIO var
            if b
              then i `shouldSatisfy` (< 20)
              else expectationFailure "Invariant of resources not maintained during shrinking"

As a result, debugging is broken when using around or before together with shrinking. The only way to find the real problem in that case is to turn off shrinking.)

I'm trying to fix this problem in sydtest at the moment but hspec has the same issue so I figured I'd report it so that it can be fixed in hspec as well.