Add tests

node/pkg/common/channel_utils_test.go

@@ -0,0 +1,80 @@
+package common
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+const myDelay = time.Millisecond * 100
+const myMaxSize = 2
+const myQueueSize = myMaxSize * 10
+
+func TestReadFromChannelWithTimeout_NoData(t *testing.T) {
+	ctx := context.Background()
+	myChan := make(chan int, myQueueSize)
+
+	// No data should timeout.
+	timeout, cancel := context.WithTimeout(ctx, myDelay)
+	defer cancel()
+	observations, err := ReadFromChannelWithTimeout[int](timeout, myChan, myMaxSize)
+	assert.Equal(t, err, context.DeadlineExceeded)
+	assert.Equal(t, 0, len(observations))
+}
+
+func TestReadFromChannelWithTimeout_SomeData(t *testing.T) {
+	ctx := context.Background()
+	myChan := make(chan int, myQueueSize)
+	myChan <- 1
+
+	// Some data but not enough to fill a message should timeout and return the data.
+	timeout, cancel := context.WithTimeout(ctx, myDelay)
+	defer cancel()
+	observations, err := ReadFromChannelWithTimeout[int](timeout, myChan, myMaxSize)
+	assert.Equal(t, err, context.DeadlineExceeded)
+	require.Equal(t, 1, len(observations))
+	assert.Equal(t, 1, observations[0])
+}
+
+func TestReadFromChannelWithTimeout_JustEnoughData(t *testing.T) {
+	ctx := context.Background()
+	myChan := make(chan int, myQueueSize)
+	myChan <- 1
+	myChan <- 2
+
+	// Just enough data should return the data and no error.
+	timeout, cancel := context.WithTimeout(ctx, myDelay)
+	defer cancel()
+	observations, err := ReadFromChannelWithTimeout[int](timeout, myChan, myMaxSize)
+	assert.NoError(t, err)
+	require.Equal(t, 2, len(observations))
+	assert.Equal(t, 1, observations[0])
+	assert.Equal(t, 2, observations[1])
+}
+
+func TestReadFromChannelWithTimeout_TooMuchData(t *testing.T) {
+	ctx := context.Background()
+	myChan := make(chan int, myQueueSize)
+	myChan <- 1
+	myChan <- 2
+	myChan <- 3
+
+	// If there is more data than will fit, it should immediately return a full message, then timeout and return the remainder.
+	timeout, cancel := context.WithTimeout(ctx, myDelay)
+	defer cancel()
+	observations, err := ReadFromChannelWithTimeout[int](timeout, myChan, myMaxSize)
+	assert.NoError(t, err)
+	require.Equal(t, 2, len(observations))
+	assert.Equal(t, 1, observations[0])
+	assert.Equal(t, 2, observations[1])
+
+	timeout2, cancel2 := context.WithTimeout(ctx, myDelay)
+	defer cancel2()
+	observations, err = ReadFromChannelWithTimeout[int](timeout2, myChan, myMaxSize)
+	assert.Equal(t, err, context.DeadlineExceeded)
+	require.Equal(t, 1, len(observations))
+	assert.Equal(t, 3, observations[0])
+}