Add tests for Celo2 Signer compatibility with both Celo1 and Celo2 tr…

…ansactions (#308)

* Fix typo

* Add unit tests for forks

* Add unit tests for Celo signer

* Format code

* Simplify Test_forks_activeForks and Test_forks_findTxFuncs

* Remove Test_forks_findTxFuncs

core/types/celo_transaction_signing_forks.go

@@ -96,11 +96,11 @@ func (c *celoLegacy) txFuncs(tx *Transaction) *txFuncs {
 		return celoLegacyTxFuncs
 	case t == DynamicFeeTxType:
 		// We handle the dynamic fee tx type here because we need to handle
-		// migrated dynamic fee txs. These were enabeled in celo in the Espresso
+		// migrated dynamic fee txs. These were enabled in celo in the Espresso
 		// hardfork, which doesn't have any analogue in op-geth. Even though
 		// op-geth does enable support for dynamic fee txs in the London
 		// hardfork (which we set to the cel2 block) that fork contains a lot of
-		// changes that were not part of Espresso. So instead we ned to handle
+		// changes that were not part of Espresso. So instead we need to handle
 		// DynamicFeeTxTypes here.
 		return dynamicFeeTxFuncs
 	case t == AccessListTxType:

core/types/celo_transaction_signing_forks_test.go

@@ -0,0 +1,36 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/ethereum/go-ethereum/params"
+	"github.com/stretchr/testify/assert"
+)
+
+// Test_forks_activeForks tests that the correct forks are returned for a given block time and chain config
+func Test_forks_activeForks(t *testing.T) {
+	t.Parallel()
+
+	cel2Time := uint64(1000)
+
+	t.Run("Non-Celo", func(t *testing.T) {
+		config := &params.ChainConfig{
+			Cel2Time: nil,
+		}
+		assert.Equal(t, []fork(nil), celoForks.activeForks(1000, config))
+	})
+
+	t.Run("Celo1", func(t *testing.T) {
+		config := &params.ChainConfig{
+			Cel2Time: &cel2Time,
+		}
+		assert.Equal(t, []fork{&celoLegacy{}}, celoForks.activeForks(500, config))
+	})
+
+	t.Run("Celo2", func(t *testing.T) {
+		config := &params.ChainConfig{
+			Cel2Time: &cel2Time,
+		}
+		assert.Equal(t, []fork{&cel2{}, &celoLegacy{}}, celoForks.activeForks(1000, config))
+	})
+}