chore(dot): remove unneeded error functions (#2790)

dot/core/errors.go

@@ -5,7 +5,6 @@ package core
 
 import (
 	"errors"
-	"fmt"
 )
 
 var (
@@ -23,18 +22,3 @@ var (
 	// ErrEmptyRuntimeCode is returned when the storage :code is empty
 	ErrEmptyRuntimeCode = errors.New("new :code is empty")
 )
-
-// ErrNilChannel is returned if a channel is nil
-func ErrNilChannel(s string) error {
-	return fmt.Errorf("cannot have nil channel %s", s)
-}
-
-// ErrMessageCast is returned if unable to cast a network.Message to a type
-func ErrMessageCast(s string) error {
-	return fmt.Errorf("could not cast network.Message to %s", s)
-}
-
-// ErrUnsupportedMsgType is returned if we receive an unknown message type
-func ErrUnsupportedMsgType(d byte) error {
-	return fmt.Errorf("received unsupported message type %d", d)
-}

dot/sync/errors.go

@@ -5,7 +5,6 @@ package sync
 
 import (
 	"errors"
-	"fmt"
 )
 
 var (
@@ -40,8 +39,3 @@ var (
 	errStartAndEndMismatch          = errors.New("request start and end hash are not on the same chain")
 	errFailedToGetDescendant        = errors.New("failed to find descendant block")
 )
-
-// ErrNilChannel is returned if a channel is nil
-func ErrNilChannel(s string) error {
-	return fmt.Errorf("cannot have nil channel %s", s)
-}