Return error instead of panicking

Signed-off-by: Christian Haudum <christian.haudum@gmail.com>

pkg/util/mempool/pool.go

@@ -89,16 +89,16 @@ func New(buckets []Bucket) *MemPool {
 }
 
 // Get satisfies Allocator interface
-// Allocating a buffer from an exhausted pool/slab will return an error.
-// Allocating a buffer that exceeds the largest slab size will cause a panic.
+// Allocating a buffer from an exhausted pool/slab, or allocating a buffer that
+// exceeds the largest slab size will return an error.
 func (a *MemPool) Get(size int) ([]byte, error) {
 	for i := 0; i < len(a.slabs); i++ {
 		if a.slabs[i].size < size {
 			continue
 		}
 		return a.slabs[i].get(size)
 	}
-	panic(fmt.Sprintf("no slab found for size: %d", size))
+	return nil, fmt.Errorf("no slab found for size: %d", size)
 }
 
 // Put satisfies Allocator interface

pkg/util/mempool/pool_test.go

@@ -14,18 +14,16 @@ func TestMemPool(t *testing.T) {
 
 	t.Run("empty pool", func(t *testing.T) {
 		pool := New([]Bucket{})
-		require.Panics(t, func() {
-			_, _ = pool.Get(128)
-		})
+		_, err := pool.Get(256)
+		require.Error(t, err)
 	})
 
 	t.Run("requested size too big", func(t *testing.T) {
 		pool := New([]Bucket{
 			{Size: 1, Capacity: 128},
 		})
-		require.Panics(t, func() {
-			_, _ = pool.Get(256)
-		})
+		_, err := pool.Get(256)
+		require.Error(t, err)
 	})
 
 	t.Run("requested size within bucket", func(t *testing.T) {