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|
package pipeline
import (
"context"
"fmt"
"sync/atomic"
"testing"
"time"
)
func TestRun_Passthrough(t *testing.T) {
t.Parallel()
input := make(chan int, 3)
input <- 1
input <- 2
input <- 3
close(input)
out := Run(t.Context(), input)
var got []int
for v := range out {
got = append(got, v)
}
if len(got) != 3 {
t.Fatalf("expected 3 items, got %d", len(got))
}
}
func TestRun_NilInput(t *testing.T) {
t.Parallel()
defer func() {
if r := recover(); r == nil {
t.Error("expected panic for nil input")
}
}()
Run[int](t.Context(), nil)
}
func TestRun_Composition(t *testing.T) {
t.Parallel()
input := make(chan int, 10)
for i := 1; i <= 10; i++ {
input <- i
}
close(input)
out := Run(t.Context(), input,
Filter(func(v int) bool { return v%2 == 0 }),
Map(1, func(_ context.Context, v int) (int, bool) {
return v * 2, true
}),
)
var got []int
for v := range out {
got = append(got, v)
}
if len(got) != 5 {
t.Fatalf("expected 5 items, got %d: %v", len(got), got)
}
sum := 0
for _, v := range got {
sum += v
}
if sum != 60 {
t.Fatalf("expected sum 60, got %d", sum)
}
}
func TestRun_Backpressure(t *testing.T) {
t.Parallel()
input := make(chan int)
consumed := make(chan int, 10)
out := Run(t.Context(), input,
Map(1, func(_ context.Context, v int) (int, bool) {
consumed <- v
return v, true
}),
)
input <- 42
v := <-consumed
if v != 42 {
t.Fatalf("expected 42, got %d", v)
}
select {
case input <- 99:
t.Fatal("producer was not blocked")
case <-time.After(50 * time.Millisecond):
}
go func() {
for range out {
}
}()
close(input)
}
func TestRun_GracefulDrain(t *testing.T) {
t.Parallel()
input := make(chan int, 5)
for i := 1; i <= 5; i++ {
input <- i
}
close(input)
var count atomic.Int32
out := Run(t.Context(), input,
Sink(2, func(_ context.Context, v int) {
count.Add(1)
}),
)
for range out {
}
if count.Load() != 5 {
t.Fatalf("expected all 5 items drained, got %d", count.Load())
}
}
func TestRun_Cancellation(t *testing.T) {
t.Parallel()
ctx, cancel := context.WithCancel(t.Context())
input := make(chan int)
out := Run(ctx, input,
Map(1, func(_ context.Context, v int) (int, bool) {
return v, true
}),
)
go func() {
select {
case input <- 1:
case <-ctx.Done():
}
}()
cancel()
done := make(chan struct{})
go func() {
for range out {
}
close(done)
}()
select {
case <-done:
case <-time.After(time.Second):
t.Fatal("pipeline did not shut down after cancellation")
}
}
func TestRun_ErrorPropagation(t *testing.T) {
t.Parallel()
ctx, cancel := context.WithCancelCause(t.Context())
defer cancel(nil)
input := make(chan int, 5)
for i := 1; i <= 5; i++ {
input <- i
}
close(input)
sentinel := fmt.Errorf("bad item")
out := Run(ctx, input,
Map(1, func(_ context.Context, v int) (int, bool) {
if v == 3 {
cancel(sentinel)
return v, false
}
return v * 2, true
}),
)
for range out {
}
if cause := context.Cause(ctx); cause != sentinel {
t.Fatalf("expected sentinel error, got: %v", cause)
}
}
func TestObserver(t *testing.T) {
t.Parallel()
var items, drops atomic.Int32
doneCh := make(chan struct{})
obs := &testObserver{
onItem: func() { items.Add(1) },
onDrop: func() { drops.Add(1) },
onDone: func() { close(doneCh) },
}
input := make(chan int, 6)
for i := 1; i <= 6; i++ {
input <- i
}
close(input)
out := Run(t.Context(), input,
Filter(func(v int) bool { return v%2 == 0 }, WithObserver(obs)),
)
for range out {
}
<-doneCh
if items.Load() != 3 {
t.Errorf("expected 3 items, got %d", items.Load())
}
if drops.Load() != 3 {
t.Errorf("expected 3 drops, got %d", drops.Load())
}
}
type testObserver struct {
onItem func()
onDrop func()
onDone func()
}
func (o *testObserver) OnItem() {
if o.onItem != nil {
o.onItem()
}
}
func (o *testObserver) OnDrop() {
if o.onDrop != nil {
o.onDrop()
}
}
func (o *testObserver) OnDone() {
if o.onDone != nil {
o.onDone()
}
}
|
