test: Add TxInjector interface and integrate with test suites (#50)

Introduced the TxInjector interface for injecting transactions into test cases. Updated ExecutorSuite, proxy_test, and DummyTestSuite to utilize TxInjector. Adjusted test assertions to validate transaction injection functionality.

Resolves #15

proxy/grpc/proxy_test.go

@@ -73,6 +73,7 @@ func (s *ProxyTestSuite) SetupTest() {
 
 	s.client = client
 	s.Exec = client
+	s.TxInjector = exec
 	s.cleanup = func() {
 		_ = client.Stop()
 		s.server.Stop()

test/dummy_test.go

@@ -16,7 +16,9 @@ type DummyTestSuite struct {
 }
 
 func (s *DummyTestSuite) SetupTest() {
-	s.Exec = NewDummyExecutor()
+	dummy := NewDummyExecutor()
+	s.Exec = dummy
+	s.TxInjector = dummy
 }
 
 func TestDummySuite(t *testing.T) {

test/suite.go

@@ -13,7 +13,13 @@ import (
 // ExecutorSuite is a reusable test suite for Execution API implementations.
 type ExecutorSuite struct {
 	suite.Suite
-	Exec execution.Executor
+	Exec       execution.Executor
+	TxInjector TxInjector
+}
+
+// TxInjector provides an interface for injecting transactions into a test suite.
+type TxInjector interface {
+	InjectTx(tx types.Tx)
 }
 
 // TestInitChain tests InitChain method.
@@ -30,9 +36,24 @@ func (s *ExecutorSuite) TestInitChain() {
 
 // TestGetTxs tests GetTxs method.
 func (s *ExecutorSuite) TestGetTxs() {
+	s.skipIfInjectorNotSet()
+
+	tx1 := types.Tx("tx1")
+	tx2 := types.Tx("tx2")
+
+	s.TxInjector.InjectTx(tx1)
+	s.TxInjector.InjectTx(tx2)
 	txs, err := s.Exec.GetTxs(context.TODO())
 	s.Require().NoError(err)
-	s.Empty(txs)
+	s.Require().Len(txs, 2)
+	s.Require().Contains(txs, tx1)
+	s.Require().Contains(txs, tx2)
+}
+
+func (s *ExecutorSuite) skipIfInjectorNotSet() {
+	if s.TxInjector == nil {
+		s.T().Skipf("Skipping %s because TxInjector is not provided", s.T().Name())
+	}
 }
 
 // TestExecuteTxs tests ExecuteTxs method.