core: added a new RemovedLogEvent

When a chain reorganisation occurs we collect the logs that were deleted
during the chain reorganisation. The removed logs are posted to the
event mux indicating that those were deleted during the reorg.

1 files changed, 43 insertions, 0 deletions

diff --git a/core/blockchain_test.go b/core/blockchain_test.go
index 6e1c5fdc7..b4ac1696a 100644
--- a/core/blockchain_test.go
+++ b/core/blockchain_test.go
@@ -963,3 +963,46 @@ func TestChainTxReorgs(t *testing.T) {
 		}
 	}
 }
+
+func TestLogReorgs(t *testing.T) {
+	params.MinGasLimit = big.NewInt(125000)      // Minimum the gas limit may ever be.
+	params.GenesisGasLimit = big.NewInt(3141592) // Gas limit of the Genesis block.
+
+	var (
+		key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+		addr1   = crypto.PubkeyToAddress(key1.PublicKey)
+		db, _   = ethdb.NewMemDatabase()
+		// this code generates a log
+		code = common.Hex2Bytes("60606040525b7f24ec1d3ff24c2f6ff210738839dbc339cd45a5294d85c79361016243157aae7b60405180905060405180910390a15b600a8060416000396000f360606040526008565b00")
+	)
+	genesis := WriteGenesisBlockForTesting(db,
+		GenesisAccount{addr1, big.NewInt(10000000000000)},
+	)
+
+	evmux := &event.TypeMux{}
+	blockchain, _ := NewBlockChain(db, FakePow{}, evmux)
+
+	subs := evmux.Subscribe(RemovedLogEvent{})
+	chain, _ := GenerateChain(genesis, db, 2, func(i int, gen *BlockGen) {
+		if i == 1 {
+			tx, err := types.NewContractCreation(gen.TxNonce(addr1), new(big.Int), big.NewInt(1000000), new(big.Int), code).SignECDSA(key1)
+			if err != nil {
+				t.Fatalf("failed to create tx: %v", err)
+			}
+			gen.AddTx(tx)
+		}
+	})
+	if _, err := blockchain.InsertChain(chain); err != nil {
+		t.Fatalf("failed to insert chain: %v", err)
+	}
+
+	chain, _ = GenerateChain(genesis, db, 3, func(i int, gen *BlockGen) {})
+	if _, err := blockchain.InsertChain(chain); err != nil {
+		t.Fatalf("failed to insert forked chain: %v", err)
+	}
+
+	ev := <-subs.Chan()
+	if len(ev.Data.(RemovedLogEvent).Logs) == 0 {
+		t.Error("expected logs")
+	}
+}