Move retry logic to errors.IsRetrialbeError

Also added unit tests.

errors/types.go

@@ -2,6 +2,7 @@ package errors
 
 import (
 	"fmt"
+	"net/url"
 
 	"github.com/pkg/errors"
 )
@@ -134,6 +135,9 @@ func IsRetriableError(err error) bool {
 	}); ok {
 		return e.RetriableError()
 	}
+	if cause, ok := Cause(err).(*url.Error); ok {
+		return cause.Temporary() || cause.Timeout()
+	}
 	if parent := parentOf(err); parent != nil {
 		return IsRetriableError(parent)
 	}

errors/types_test.go

@@ -0,0 +1,46 @@
+package errors_test
+
+import (
+	"net/url"
+	"testing"
+
+	"github.com/git-lfs/git-lfs/errors"
+	"github.com/stretchr/testify/assert"
+)
+
+type TemporaryError struct {
+}
+
+func (e TemporaryError) Error() string {
+	return ""
+}
+
+func (e TemporaryError) Temporary() bool {
+	return true
+}
+
+type TimeoutError struct {
+}
+
+func (e TimeoutError) Error() string {
+	return ""
+}
+
+func (e TimeoutError) Timeout() bool {
+	return true
+}
+
+func TestCanRetryOnTemporaryError(t *testing.T) {
+	err := &url.Error{Err: TemporaryError{}}
+	assert.True(t, errors.IsRetriableError(err))
+}
+
+func TestCanRetryOnTimeoutError(t *testing.T) {
+	err := &url.Error{Err: TimeoutError{}}
+	assert.True(t, errors.IsRetriableError(err))
+}
+
+func TestCannotRetryOnGenericUrlError(t *testing.T) {
+	err := &url.Error{Err: errors.New("")}
+	assert.False(t, errors.IsRetriableError(err))
+}

tq/transfer_queue.go

@@ -1,7 +1,6 @@
 package tq
 
 import (
-	"net/url"
 	"os"
 	"sort"
 	"sync"
@@ -634,12 +633,7 @@ func (q *TransferQueue) run() {
 
 // canRetry returns whether or not the given error "err" is retriable.
 func (q *TransferQueue) canRetry(err error) bool {
-	switch cause := errors.Cause(err).(type) {
-	case *url.Error:
-		return cause.Temporary() || cause.Timeout()
-	default:
-		return errors.IsRetriableError(err)
-	}
+	return errors.IsRetriableError(err)
 }
 
 // canRetryObject returns whether the given error is retriable for the object