✅ [channel/test,backend/eth/channel] Generic subscription test

Signed-off-by: Matthias Geihs <[email protected]>

Author: matthiasgeihs

backend/ethereum/channel/subscription_test.go

@@ -0,0 +1,112 @@
+// Copyright 2021 - See NOTICE file for copyright holders.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package channel_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"perun.network/go-perun/backend/ethereum/channel/test"
+	"perun.network/go-perun/channel"
+	channeltest "perun.network/go-perun/channel/test"
+	pkgtest "perun.network/go-perun/pkg/test"
+)
+
+func TestSubscription(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	rng := pkgtest.Prng(t)
+	numParts := 2 + rng.Intn(maxNumParts-2)
+	setup := test.NewSetup(t, rng, numParts, blockInterval)
+	adjSetup := newAdjudicatorSetup(setup)
+	adj := adjSetup.Adjudicator()
+
+	req, subChannels := adjSetup.newAdjudicatorReq(ctx, rng, channeltest.WithoutApp()), []channel.SignedState{}
+	sub, err := adj.Subscribe(ctx, req.Params.ID())
+	require.NoError(t, err, "subscribing")
+
+	subSetup := newSubscriptionSetup(sub, adj, req, subChannels)
+	channeltest.TestSubscription(ctx, t, subSetup)
+}
+
+type subscriptionSetup struct {
+	adj         channel.Adjudicator
+	sub         *testSubscription
+	req         *channel.AdjudicatorReq
+	subChannels []channel.SignedState
+}
+
+func newSubscriptionSetup(
+	sub channel.AdjudicatorSubscription,
+	adj channel.Adjudicator,
+	req *channel.AdjudicatorReq,
+	subChannels []channel.SignedState,
+) *subscriptionSetup {
+	return &subscriptionSetup{
+		sub: &testSubscription{
+			emitProgressed:          false,
+			req:                     req,
+			AdjudicatorSubscription: sub,
+		},
+		adj:         adj,
+		req:         req,
+		subChannels: subChannels,
+	}
+}
+
+type testSubscription struct {
+	channel.AdjudicatorSubscription
+	emitProgressed bool
+	req            *channel.AdjudicatorReq
+}
+
+// Next emulates app channel functionality because app channels are not supported yet.
+func (s *testSubscription) Next() channel.AdjudicatorEvent {
+	if s.emitProgressed {
+		s.emitProgressed = false
+		return channel.NewProgressedEvent(s.req.Tx.ID, &channel.ElapsedTimeout{}, s.req.Tx.State, s.req.Idx)
+	}
+	return s.AdjudicatorSubscription.Next()
+}
+
+func (s *subscriptionSetup) Subscription() channel.AdjudicatorSubscription {
+	return s.sub
+}
+
+// EmitRegistered operates the adjudicator so that a registered event should be emitted.
+func (s *subscriptionSetup) EmitRegistered(ctx context.Context) (channel.Params, channel.State) {
+	err := s.adj.Register(ctx, *s.req, s.subChannels)
+	if err != nil {
+		panic(err)
+	}
+	return *s.req.Params, *s.req.Tx.State
+}
+
+// EmitProgressed emulates app channel functionality because app channels are not supported yet.
+func (s *subscriptionSetup) EmitProgressed(ctx context.Context) (channel.Params, channel.State) {
+	s.sub.emitProgressed = true
+	return *s.req.Params, *s.req.Tx.State
+}
+
+// EmitRegistered operates the adjudicator so that a concluded event should be emitted.
+func (s *subscriptionSetup) EmitConcluded(ctx context.Context) channel.Params {
+	err := s.adj.Withdraw(ctx, *s.req, channeltest.MakeStateMapFromSignedStates(s.subChannels...))
+	if err != nil {
+		panic(err)
+	}
+	return *s.req.Params
+}

channel/test/subscription.go

@@ -0,0 +1,76 @@
+//  Copyright 2021 - See NOTICE file for copyright holders.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+
+package test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"perun.network/go-perun/channel"
+)
+
+// SubscriptionTestSetup represents a setup for testing a subscription implementation.
+//
+// Subscription should return an instance of the subscription implementation.
+// EmitRegistered should make the subscription emit a registered event.
+// EmitProgressed should make the subscription emit a progressed event.
+// EmitConcluded should make the subscription emit a concluded event.
+type SubscriptionTestSetup interface {
+	Subscription() channel.AdjudicatorSubscription
+	EmitRegistered(context.Context) (channel.Params, channel.State)
+	EmitProgressed(context.Context) (channel.Params, channel.State)
+	EmitConcluded(context.Context) channel.Params
+}
+
+func TestSubscription(ctx context.Context, t *testing.T, s SubscriptionTestSetup) {
+	sub := s.Subscription()
+
+	{
+		params, state := s.EmitRegistered(ctx)
+		e, ok := sub.Next().(*channel.RegisteredEvent)
+		assert.True(t, ok, "registered")
+		assert.True(t, e.ID() == params.ID(), "equal ID")
+		assert.True(t, e.State.Equal(&state) == nil, "equal state")
+		err := e.Timeout().Wait(ctx)
+		assert.NoError(t, err, "registered: waiting")
+	}
+
+	{
+		params, state := s.EmitProgressed(ctx)
+		e, ok := sub.Next().(*channel.ProgressedEvent)
+		assert.True(t, ok, "progressed")
+		assert.True(t, e.ID() == params.ID(), "equal ID")
+		assert.True(t, e.State.Equal(&state) == nil, "equal state")
+		err := e.Timeout().Wait(ctx)
+		assert.NoError(t, err, "progressed: waiting")
+	}
+
+	{
+		params := s.EmitConcluded(ctx)
+		e, ok := sub.Next().(*channel.ConcludedEvent)
+		assert.True(t, ok, "concluded")
+		assert.True(t, e.ID() == params.ID(), "equal ID")
+		err := e.Timeout().Wait(ctx)
+		assert.NoError(t, err, "concluded: waiting")
+	}
+
+	{
+		err := sub.Close()
+		assert.NoError(t, err, "close")
+		err = sub.Err()
+		assert.NoError(t, err, "err")
+	}
+}