Refactor submit returns

README.md

@@ -49,7 +49,7 @@ func main() {
 	}
 
 	for i := range bazookas {
-		pool.Submit(context.TODO(), &bazookas[i])
+		_ = pool.Submit(context.TODO(), &bazookas[i])
 	}
 
 	_ = pool.GracefulShutdown()

example_test.go

@@ -36,7 +36,7 @@ func Example() {
 	}
 
 	for i := range bazookas {
-		pool.Submit(context.TODO(), &bazookas[i])
+		_ = pool.Submit(context.TODO(), &bazookas[i])
 	}
 
 	if err := pool.GracefulShutdown(); err != nil {

workerpool.go

@@ -98,18 +98,23 @@ func (p *Pool[T]) worker() {
 	}
 }
 
+var (
+	ErrPoolClosed    = errors.New("pool is closed")
+	ErrTaskCancelled = errors.New("task context cancelled")
+)
+
 // Submit sends a task to the pool. Blocks if the task channel is full.
 // Returns false if the pool is shutting down or the context was cancelled.
-func (p *Pool[T]) Submit(ctx context.Context, task T) bool {
+func (p *Pool[T]) Submit(ctx context.Context, task T) error {
 	select {
 	case <-ctx.Done():
-		return false
+		return ErrTaskCancelled
 	case <-p.ctx.Done(): // forcefully terminate via ctx
-		return false
+		return ErrPoolClosed
 	case <-p.stop: // terminated via graceful shutdown
-		return false
+		return ErrPoolClosed
 	case p.entries <- entry[T]{ctx: ctx, job: task}:
-		return true
+		return nil
 	}
 }
 

workerpool_test.go

@@ -2,6 +2,7 @@ package workerpool
 
 import (
 	"context"
+	"errors"
 	"sync"
 	"sync/atomic"
 	"testing"
@@ -36,7 +37,7 @@ func TestNew(t *testing.T) {
 			counter: &counter,
 		}
 
-		if !pool.Submit(context.TODO(), task) {
+		if err := pool.Submit(context.TODO(), task); err != nil {
 			t.Error("failed to submit task")
 		}
 
@@ -64,7 +65,7 @@ func TestPool_WithBuffer(t *testing.T) {
 			counter: &counter,
 		}
 
-		if !pool.Submit(context.TODO(), task) {
+		if err := pool.Submit(context.TODO(), task); err != nil {
 			t.Error("failed to submit task")
 		}
 	}
@@ -94,7 +95,7 @@ func TestPool_Submit(t *testing.T) {
 				counter: &counter,
 			}
 
-			if !pool.Submit(context.TODO(), task) {
+			if err := pool.Submit(context.TODO(), task); err != nil {
 				t.Error("failed to submit task")
 			}
 		}
@@ -330,7 +331,7 @@ func TestPool_GracefulShutdown(t *testing.T) {
 				},
 			}
 
-			if !pool.Submit(context.TODO(), task1) {
+			if err := pool.Submit(context.TODO(), task1); err != nil {
 				t.Error("expected Submit to return true")
 			}
 
@@ -351,9 +352,15 @@ func TestPool_GracefulShutdown(t *testing.T) {
 				counter: &counter,
 			}
 
-			if pool.Submit(context.TODO(), task2) {
-				t.Error("expected Submit to return false after shutdown")
+			err := pool.Submit(context.TODO(), task2)
+			if err == nil {
+				t.Error("expected Submit to return error after shutdown")
 			}
+
+			if !errors.Is(err, ErrPoolClosed) {
+				t.Errorf("expected error to be %v, got %v", ErrPoolClosed, err)
+			}
+
 			close(blocker)
 
 			if err := <-shutdownDone; err != nil {