bugfix: Remove dangling wallet env instance

Author: promag

src/wallet/db.cpp

@@ -694,8 +694,10 @@ void BerkeleyEnvironment::Flush(bool fShutdown)
             if (mapFileUseCount.empty()) {
                 dbenv->log_archive(&listp, DB_ARCH_REMOVE);
                 Close();
-                if (!fMockDb)
+                if (!fMockDb) {
                     fs::remove_all(fs::path(strPath) / "database");
+                }
+                g_dbenvs.erase(strPath);
             }
         }
     }
@@ -794,5 +796,6 @@ void BerkeleyDatabase::Flush(bool shutdown)
 {
     if (!IsDummy()) {
         env->Flush(shutdown);
+        if (shutdown) env = nullptr;
     }
 }

test/functional/wallet_multiwallet.py

@@ -256,5 +256,10 @@ def run_test(self):
         assert_equal(self.nodes[0].listwallets(), [])
         assert_raises_rpc_error(-32601, "Method not found (wallet method is disabled because no wallet is loaded)", self.nodes[0].getwalletinfo)
 
+        # Successfully load a previously unloaded wallet
+        self.nodes[0].loadwallet('w1')
+        assert_equal(self.nodes[0].listwallets(), ['w1'])
+        assert_equal(w1.getwalletinfo()['walletname'], 'w1')
+
 if __name__ == '__main__':
     MultiWalletTest().main()