Implementation of a ring buffer complete.

Author: dustinhiatt-wf

queue/ring_test.go

@@ -0,0 +1,290 @@
+/*
+Copyright 2014 Workiva, LLC
+
+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 queue
+
+import (
+	"sync"
+	"sync/atomic"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRingInsert(t *testing.T) {
+	rb := NewRingBuffer(5)
+	assert.Equal(t, uint64(8), rb.Cap())
+
+	err := rb.Put(5)
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	result, err := rb.Get()
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	assert.Equal(t, 5, result)
+}
+
+func TestRingMultipleInserts(t *testing.T) {
+	rb := NewRingBuffer(5)
+
+	err := rb.Put(1)
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	err = rb.Put(2)
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	result, err := rb.Get()
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	assert.Equal(t, 1, result)
+
+	result, err = rb.Get()
+	if assert.Nil(t, err) {
+		return
+	}
+
+	assert.Equal(t, 2, result)
+}
+
+func TestIntertwinedGetAndPut(t *testing.T) {
+	rb := NewRingBuffer(5)
+	err := rb.Put(1)
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	result, err := rb.Get()
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	assert.Equal(t, 1, result)
+
+	err = rb.Put(2)
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	result, err = rb.Get()
+	if !assert.Nil(t, err) {
+		return
+	}
+
+	assert.Equal(t, 2, result)
+}
+
+func TestPutToFull(t *testing.T) {
+	rb := NewRingBuffer(3)
+
+	for i := 0; i < 4; i++ {
+		err := rb.Put(i)
+		if !assert.Nil(t, err) {
+			return
+		}
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(2)
+
+	go func() {
+		err := rb.Put(4)
+		assert.Nil(t, err)
+		wg.Done()
+	}()
+
+	go func() {
+		defer wg.Done()
+		result, err := rb.Get()
+		if !assert.Nil(t, err) {
+			return
+		}
+
+		assert.Equal(t, 0, result)
+	}()
+
+	wg.Wait()
+}
+
+func TestRingGetEmpty(t *testing.T) {
+	rb := NewRingBuffer(3)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	// want to kick off this consumer to ensure it blocks
+	go func() {
+		wg.Done()
+		result, err := rb.Get()
+		assert.Nil(t, err)
+		assert.Equal(t, 0, result)
+		wg.Done()
+	}()
+
+	wg.Wait()
+	wg.Add(2)
+
+	go func() {
+		defer wg.Done()
+		err := rb.Put(0)
+		assert.Nil(t, err)
+	}()
+
+	wg.Wait()
+}
+
+func TestRingLen(t *testing.T) {
+	rb := NewRingBuffer(4)
+	assert.Equal(t, uint64(0), rb.Len())
+
+	rb.Put(1)
+	assert.Equal(t, uint64(1), rb.Len())
+
+	rb.Get()
+	assert.Equal(t, uint64(0), rb.Len())
+
+	for i := 0; i < 4; i++ {
+		rb.Put(1)
+	}
+	assert.Equal(t, uint64(4), rb.Len())
+
+	rb.Get()
+	assert.Equal(t, uint64(3), rb.Len())
+}
+
+func TestDisposeOnGet(t *testing.T) {
+	numThreads := 8
+	var wg sync.WaitGroup
+	wg.Add(numThreads)
+	rb := NewRingBuffer(4)
+	var spunUp sync.WaitGroup
+	spunUp.Add(numThreads)
+
+	for i := 0; i < numThreads; i++ {
+		go func() {
+			spunUp.Done()
+			defer wg.Done()
+			_, err := rb.Get()
+			assert.NotNil(t, err)
+		}()
+	}
+
+	spunUp.Wait()
+
+	rb.Dispose()
+
+	wg.Wait()
+
+	assert.True(t, rb.IsDisposed())
+}
+
+func TestDisposeOnPut(t *testing.T) {
+	numThreads := 8
+	var wg sync.WaitGroup
+	wg.Add(numThreads)
+	rb := NewRingBuffer(4)
+	var spunUp sync.WaitGroup
+	spunUp.Add(numThreads)
+
+	// fill up the queue
+	for i := 0; i < 4; i++ {
+		rb.Put(i)
+	}
+
+	// it's now full
+	for i := 0; i < numThreads; i++ {
+		go func(i int) {
+			spunUp.Done()
+			defer wg.Done()
+			err := rb.Put(i)
+			assert.NotNil(t, err)
+		}(i)
+	}
+
+	spunUp.Wait()
+
+	rb.Dispose()
+
+	wg.Wait()
+
+	assert.True(t, rb.IsDisposed())
+}
+
+func BenchmarkRBLifeCycle(b *testing.B) {
+	rb := NewRingBuffer(64)
+
+	counter := uint64(0)
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	go func() {
+		defer wg.Done()
+		for {
+			_, err := rb.Get()
+			assert.Nil(b, err)
+
+			if atomic.AddUint64(&counter, 1) == uint64(b.N) {
+				return
+			}
+		}
+	}()
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		rb.Put(i)
+	}
+
+	wg.Wait()
+}
+
+func BenchmarkRBPut(b *testing.B) {
+	rbs := make([]*RingBuffer, 0, b.N)
+
+	for i := 0; i < b.N; i++ {
+		rbs = append(rbs, NewRingBuffer(2))
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		rbs[i].Put(i)
+	}
+}
+
+func BenchmarkRBGet(b *testing.B) {
+	rbs := make([]*RingBuffer, 0, b.N)
+
+	for i := 0; i < b.N; i++ {
+		rbs = append(rbs, NewRingBuffer(2))
+		rbs[i].Put(i)
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		rbs[i].Get()
+	}
+}