LedgerDB.TestInternals: add getNumLedgerTablesHandles

for testing that we do not leak any, in a follow-up commit

Author: amesgen

ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/Storage/LedgerDB/API.hs

@@ -302,6 +302,9 @@ data TestInternals m l blk = TestInternals
   , reapplyThenPushNOW :: blk -> m ()
   , truncateSnapshots :: m ()
   , closeLedgerDB :: m ()
+  , getNumLedgerTablesHandles :: m Word64
+  -- ^ Get the number of referenced 'LedgerTablesHandle's for V2. For V1, this
+  -- always returns 0.
   }
   deriving NoThunks via OnlyCheckWhnfNamed "TestInternals" (TestInternals m l blk)
 

ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/Storage/LedgerDB/V1.hs

@@ -353,6 +353,7 @@ mkInternals h =
     , wipeLedgerDB = getEnv h $ void . destroySnapshots . snapshotsFs . ldbHasFS
     , closeLedgerDB = getEnv h $ bsClose . ldbBackingStore
     , truncateSnapshots = getEnv h $ void . implIntTruncateSnapshots . ldbHasFS
+    , getNumLedgerTablesHandles = pure 0
     }
 
 -- | Testing only! Truncate all snapshots in the DB.

ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/Storage/LedgerDB/V2.hs

@@ -231,6 +231,10 @@ mkInternals bss h =
         let LDBHandle tvar = h
          in atomically (writeTVar tvar LedgerDBClosed)
     , truncateSnapshots = getEnv h $ implIntTruncateSnapshots . ldbHasFS
+    , getNumLedgerTablesHandles = getEnv h $ \env -> do
+        l <- readTVarIO (ldbSeq env)
+        -- We always have a state at the anchor.
+        pure $ 1 + maxRollback l
     }
  where
   takeSnapshot ::

ouroboros-consensus/test/storage-test/Test/Ouroboros/Storage/LedgerDB/StateMachine.hs

@@ -132,7 +132,7 @@ initialEnvironment fsOps getLmdbDir mkTestArguments cdb = do
   pure $
     Environment
       undefined
-      (TestInternals undefined undefined undefined undefined undefined (pure ()))
+      (TestInternals undefined undefined undefined undefined undefined (pure ()) (pure 0))
       cdb
       (flip mkTestArguments lmdbDir)
       sfs