native: add nativehashes package

Similar to nativenames, instantiate once and then reuse everywhere.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

pkg/core/native/nativehashes/hashes.go

@@ -0,0 +1,34 @@
+package nativehashes
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
+	"github.com/nspcc-dev/neo-go/pkg/core/state"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+)
+
+// Hashes of all native contracts.
+var (
+	Management  util.Uint160
+	Ledger      util.Uint160
+	Neo         util.Uint160
+	Gas         util.Uint160
+	Policy      util.Uint160
+	Oracle      util.Uint160
+	Designation util.Uint160
+	Notary      util.Uint160
+	CryptoLib   util.Uint160
+	StdLib      util.Uint160
+)
+
+func init() {
+	Management = state.CreateNativeContractHash(nativenames.Management)
+	Ledger = state.CreateNativeContractHash(nativenames.Ledger)
+	Neo = state.CreateNativeContractHash(nativenames.Neo)
+	Gas = state.CreateNativeContractHash(nativenames.Gas)
+	Policy = state.CreateNativeContractHash(nativenames.Policy)
+	Oracle = state.CreateNativeContractHash(nativenames.Oracle)
+	Designation = state.CreateNativeContractHash(nativenames.Designation)
+	Notary = state.CreateNativeContractHash(nativenames.Notary)
+	CryptoLib = state.CreateNativeContractHash(nativenames.CryptoLib)
+	StdLib = state.CreateNativeContractHash(nativenames.StdLib)
+}