converge/pkg/support/iowrappers/channelreadwriter_test.go

152 lines
3.5 KiB
Go

package iowrappers
import (
"context"
"github.com/stretchr/testify/suite"
"log"
"strings"
"sync"
"testing"
"time"
)
type ChannelReadWriterTestSuite struct {
suite.Suite
ctx context.Context
cancelFunc context.CancelFunc
toChannel chan<- []byte
fromChannel <-chan []byte
conn *ChannelReadWriter
}
func TestChannelReadWriterSuite(t *testing.T) {
suite.Run(t, &ChannelReadWriterTestSuite{})
}
func (suite *ChannelReadWriterTestSuite) createChannel() {
toChannel := make(chan []byte)
fromChannel := make(chan []byte)
suite.toChannel = toChannel
suite.fromChannel = fromChannel
ctx, cancelFunc := context.WithCancel(context.Background())
ctx, timeoutCancelFunc := context.WithTimeout(ctx, 10*time.Second)
suite.ctx = ctx
suite.cancelFunc = func() {
timeoutCancelFunc()
cancelFunc()
}
suite.conn = NewChannelReadWriter(ctx, toChannel, fromChannel)
}
func (suite *ChannelReadWriterTestSuite) SetupTest() {
suite.createChannel()
}
func (suite *ChannelReadWriterTestSuite) TearDownTest() {
suite.cancelFunc()
}
type TestFunc func() any
func (suite *ChannelReadWriterTestSuite) runAndWait(functions ...TestFunc) []any {
wg := sync.WaitGroup{}
wg.Add(len(functions))
res := make([]any, len(functions))
for i, function := range functions {
go func() {
defer func() {
wg.Done()
}()
res[i] = function()
}()
}
wg.Wait()
return res
}
func (suite *ChannelReadWriterTestSuite) Test_SuccessfulCommunication() {
tests := []struct {
name string
data []string
chunkSizes []int
chunks []string
}{
{
name: "buffer_large_enough",
data: []string{"hello"},
chunkSizes: []int{10},
chunks: []string{"hello"},
},
{
name: "two_reads_required",
data: []string{"hello"},
chunkSizes: []int{3, 10},
chunks: []string{"hel", "lo"},
},
{
name: "many_reads_required",
data: []string{"hello"},
chunkSizes: []int{1, 1, 1, 1, 1},
chunks: []string{"h", "e", "l", "l", "o"},
},
{
name: "buffer_large_enough_multiple_writes",
data: []string{"hel", "lo"},
chunkSizes: []int{3, 2},
chunks: []string{"hel", "lo"},
},
{ // NOTE: no intelligence in the reader to fill up the read buffer when it is not full
// therefore, the second read will have only 1 char since the first channel read returned
// 3 of which 2 where returned in the first read call to the ChannelReadWriter.
name: "buffer_too_small_multiple_writes",
data: []string{"hel", "lo"},
chunkSizes: []int{2, 2, 2},
chunks: []string{"he", "l", "lo"},
},
}
for _, test := range tests {
suite.Run(test.name, func() {
suite.runAndWait(
func() any {
for _, d := range test.data {
select {
case <-suite.ctx.Done():
suite.FailNow("deadline reached")
log.Println("Write deadline exceeded")
case suite.toChannel <- []byte(d):
}
}
return nil
},
func() any {
remainder := strings.Join(test.data, "")
for i, chunkSize := range test.chunkSizes {
buf := make([]byte, chunkSize)
n, err := suite.conn.Read(buf)
suite.Nil(err)
suite.Equal(n, len(test.chunks[i]))
suite.Equal([]byte(remainder[:n]), buf[:n])
remainder = remainder[n:]
}
return nil
},
)
})
}
}
func (suite *ChannelReadWriterTestSuite) Test_Close() {
suite.FailNow("todo")
}
func (suite *ChannelReadWriterTestSuite) Test_CloseTwice() {
suite.FailNow("todo")
}
func (suite *ChannelReadWriterTestSuite) Test_ContextCanceled() {
suite.FailNow("todo")
}