test: added unit test for chainsync filter plugin

Signed-off-by: Jenita <jkawan@blinklabs.co>

Author: jkawan

filter/chainsync/plugin_test.go

@@ -0,0 +1,91 @@
+package chainsync
+
+import (
+	"testing"
+	"time"
+
+	"github.com/blinklabs-io/adder/event"
+	"github.com/blinklabs-io/adder/input/chainsync"
+	"github.com/blinklabs-io/adder/plugin"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPluginRegistration(t *testing.T) {
+	// Retrieve the plugin entries
+	plugins := plugin.GetPlugins(plugin.PluginTypeFilter) // Get all registered plugins
+
+	// Find the "chainsync" plugin
+	var p plugin.Plugin
+	for _, entry := range plugins {
+		if entry.Name == "chainsync" {
+			// Create a new instance of the plugin
+			p = entry.NewFromOptionsFunc()
+			break
+		}
+	}
+
+	// Verify that the plugin was found
+	assert.NotNil(t, p, "Plugin should be registered")
+
+	// Verify that the plugin implements the Plugin interface
+	_, ok := p.(plugin.Plugin)
+	assert.True(t, ok, "Plugin should implement the Plugin interface")
+}
+
+func TestPluginStartStop(t *testing.T) {
+	// Create a new plugin instance
+	p := NewFromCmdlineOptions()
+
+	// Start the plugin
+	err := p.Start()
+	assert.NoError(t, err, "Plugin should start without errors")
+
+	// Stop the plugin
+	err = p.Stop()
+	assert.NoError(t, err, "Plugin should stop without errors")
+}
+
+func TestPluginChannels(t *testing.T) {
+	// Create a new plugin instance
+	p := NewFromCmdlineOptions()
+
+	// Verify that the error channel is not nil
+	assert.NotNil(t, p.ErrorChan(), "Error channel should not be nil")
+
+	// Verify that the input channel is not nil
+	assert.NotNil(t, p.InputChan(), "Input channel should not be nil")
+
+	// Verify that the output channel is not nil
+	assert.NotNil(t, p.OutputChan(), "Output channel should not be nil")
+}
+
+func TestPluginEventProcessing(t *testing.T) {
+	// Create a new plugin instance
+	p := NewFromCmdlineOptions()
+
+	// Start the plugin
+	err := p.Start()
+	assert.NoError(t, err, "Plugin should start without errors")
+
+	// Create a test event with a TransactionEvent payload
+	testEvent := event.Event{
+		Type:      "transaction",
+		Timestamp: time.Now(),
+		Payload:   chainsync.TransactionEvent{},
+	}
+
+	// Send the event to the input channel
+	p.InputChan() <- testEvent
+
+	// Read the event from the output channel
+	select {
+	case outputEvent := <-p.OutputChan():
+		assert.Equal(t, testEvent, outputEvent, "Output event should match input event")
+	case <-time.After(1 * time.Second):
+		t.Fatal("Timeout waiting for output event")
+	}
+
+	// Stop the plugin
+	err = p.Stop()
+	assert.NoError(t, err, "Plugin should stop without errors")
+}