Hidden goroutine.

helper/README.md

@@ -301,7 +301,7 @@ fmt.Println(helper.ChanToSlice(half)) // [1, 2, 3, 4]
 func Drain[T any](c <-chan T)
 ```
 
-Drain drains the given channel.
+Drain drains the given channel. It blocks the caller.
 
 <a name="Duplicate"></a>
 ## func [Duplicate](<https://github.com/cinar/indicator/blob/v2/helper/duplicate.go#L17>)

helper/buffered.go

@@ -12,9 +12,7 @@ package helper
 func Buffered[T any](c <-chan T, size int) <-chan T {
 	result := make(chan T, size)
 
-	go func() {
-		Pipe(c, result)
-	}()
+	go Pipe(c, result)
 
 	return result
 }

helper/drain.go

@@ -4,14 +4,12 @@
 
 package helper
 
-// Drain drains the given channel.
+// Drain drains the given channel. It blocks the caller.
 func Drain[T any](c <-chan T) {
-	go func() {
-		for {
-			_, ok := <-c
-			if !ok {
-				break
-			}
+	for {
+		_, ok := <-c
+		if !ok {
+			break
 		}
-	}()
+	}
 }

helper/first.go

@@ -9,16 +9,17 @@ func First[T any](c <-chan T, count int) <-chan T {
 	result := make(chan T, cap(c))
 
 	go func() {
-		defer close(result)
 		for i := 0; i < count; i++ {
 			n, ok := <-c
 			if !ok {
-				return
+				break
 			}
 
 			result <- n
 		}
 
+		close(result)
+
 		Drain(c)
 	}()
 

helper/pipe.go

@@ -14,10 +14,8 @@ package helper
 //	helper.Pipe(input, output)
 //	fmt.println(helper.ChanToSlice(output)) // [2, 4, 6, 8]
 func Pipe[T any](f <-chan T, t chan<- T) {
-	go func() {
-		defer close(t)
-		for n := range f {
-			t <- n
-		}
-	}()
+	defer close(t)
+	for n := range f {
+		t <- n
+	}
 }

helper/pipe_test.go

@@ -16,7 +16,7 @@ func TestPipe(t *testing.T) {
 	input := helper.SliceToChan(expected)
 	output := make(chan int)
 
-	helper.Pipe(input, output)
+	go helper.Pipe(input, output)
 	actual := helper.ChanToSlice(output)
 
 	if !reflect.DeepEqual(actual, expected) {