Added tests

Author: cloudshiftchris

demux/config_test.go

@@ -27,3 +27,63 @@ func TestConfigWorks(t *testing.T) {
 	assert.NoError(t, err)
 	assert.NotNil(t, cfg)
 }
+
+func TestConfigFailsOnNilCfg(t *testing.T) {
+	cfg, err := newDemuxCfg(nil)
+	assert.EqualError(t, err, "missing demuxer configuration")
+	assert.Nil(t, cfg)
+}
+
+func TestConfigFailsOnMissingFactories(t *testing.T) {
+	externalCfg := &Cfg{
+		Handlers: []any{
+			func(ctx context.Context, event *events.APIGatewayProxyRequest) (
+				*events.APIGatewayProxyResponse,
+				error) {
+				return nil, nil
+			},
+		},
+	}
+
+	cfg, err := newDemuxCfg(externalCfg)
+	assert.EqualError(t, err, "no demux factories provided")
+	assert.Nil(t, cfg)
+}
+
+func TestConfigFailsOnMissingHandlers(t *testing.T) {
+	externalCfg := &Cfg{
+		Factories: []Factory{
+			func(ctx *EventContext) any {
+				return nil
+			},
+		},
+	}
+
+	cfg, err := newDemuxCfg(externalCfg)
+	assert.EqualError(t, err, "no demux handlers provided")
+	assert.Nil(t, cfg)
+}
+
+func TestConfigFailsOnBadHandler(t *testing.T) {
+	externalCfg := &Cfg{
+		Handlers: []any{
+			func(ctx context.Context, event error) (
+				*events.APIGatewayProxyResponse,
+				error) {
+				return nil, nil
+			},
+		},
+		Factories: []Factory{
+			func(ctx *EventContext) any {
+				return nil
+			},
+		},
+	}
+
+	cfg, err := newDemuxCfg(externalCfg)
+	assert.EqualError(
+		t,
+		err,
+		"lambda demux handler function: expected second argument of handler function to be pointer to event struct; got func(context.Context, error) (*events.APIGatewayProxyResponse, error)")
+	assert.Nil(t, cfg)
+}