Move ErrorList to util

pkg/api/errors/validation.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 	"github.com/golang/glog"
 )
 
@@ -105,30 +106,11 @@ func NewFieldNotFound(field string, value interface{}) ValidationError {
 // interface to avoid confusion where an empty ErrorList would still be an
 // error (non-nil).  To produce a single error instance from an ErrorList, use
 // the ToError() method, which will return nil for an empty ErrorList.
-type ErrorList []error
+type ErrorList util.ErrorList
-
-// This helper implements the error interface for ErrorList, but prevents
-// accidental conversion of ErrorList to error.
-type errorListInternal ErrorList
-
-// Error is part of the error interface.
-func (list errorListInternal) Error() string {
-	if len(list) == 0 {
-		return ""
-	}
-	sl := make([]string, len(list))
-	for i := range list {
-		sl[i] = list[i].Error()
-	}
-	return strings.Join(sl, "; ")
-}
 
 // ToError converts an ErrorList into a "normal" error, or nil if the list is empty.
 func (list ErrorList) ToError() error {
-	if len(list) == 0 {
+	return util.ErrorList(list).ToError()
-		return nil
-	}
-	return errorListInternal(list)
 }
 
 // Prefix adds a prefix to the Field of every ValidationError in the list. Returns

pkg/api/errors/validation_test.go

@@ -17,7 +17,6 @@ limitations under the License.
 package errors
 
 import (
-	"fmt"
 	"strings"
 	"testing"
 )
@@ -64,44 +63,6 @@ func TestValidationError(t *testing.T) {
 	}
 }
 
-func TestErrorList(t *testing.T) {
-	errList := ErrorList{}
-	if a := errList.ToError(); a != nil {
-		t.Errorf("unexpected non-nil error for empty list: %v", a)
-	}
-	if a := errorListInternal(errList).Error(); a != "" {
-		t.Errorf("expected empty string, got %v", a)
-	}
-	errList = append(errList, NewFieldInvalid("field", "value"))
-	// The fact that this compiles is the test.
-}
-
-func TestErrorListToError(t *testing.T) {
-	errList := ErrorList{}
-	err := errList.ToError()
-	if err != nil {
-		t.Errorf("expected nil, got %v", err)
-	}
-
-	testCases := []struct {
-		errs     ErrorList
-		expected string
-	}{
-		{ErrorList{fmt.Errorf("abc")}, "abc"},
-		{ErrorList{fmt.Errorf("abc"), fmt.Errorf("123")}, "abc; 123"},
-	}
-	for _, testCase := range testCases {
-		err := testCase.errs.ToError()
-		if err == nil {
-			t.Errorf("expected an error, got nil: ErrorList=%v", testCase)
-			continue
-		}
-		if err.Error() != testCase.expected {
-			t.Errorf("expected %q, got %q", testCase.expected, err.Error())
-		}
-	}
-}
-
 func TestErrListPrefix(t *testing.T) {
 	testCases := []struct {
 		Err      ValidationError

pkg/util/error_list.go

@@ -0,0 +1,55 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"fmt"
+)
+
+// ErrorList is a collection of errors.  This does not implement the error
+// interface to avoid confusion where an empty ErrorList would still be an
+// error (non-nil).  To produce a single error instance from an ErrorList, use
+// the ToError() method, which will return nil for an empty ErrorList.
+type ErrorList []error
+
+// This helper implements the error interface for ErrorList, but prevents
+// accidental conversion of ErrorList to error.
+type errorListInternal ErrorList
+
+// Error is part of the error interface.
+func (list errorListInternal) Error() string {
+	if len(list) == 0 {
+		return ""
+	}
+	if len(list) == 1 {
+		return list[0].Error()
+	}
+	result := fmt.Sprintf("[%s", list[0].Error())
+	for i := 1; i < len(list); i++ {
+		result += fmt.Sprintf(", %s", list[i].Error())
+	}
+	result += "]"
+	return result
+}
+
+// ToError converts an ErrorList into a "normal" error, or nil if the list is empty.
+func (list ErrorList) ToError() error {
+	if len(list) == 0 {
+		return nil
+	}
+	return errorListInternal(list)
+}

pkg/util/error_list_test.go

@@ -0,0 +1,51 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestErrorList(t *testing.T) {
+	errList := ErrorList{}
+	err := errList.ToError()
+	if err != nil {
+		t.Errorf("expected nil, got %v", err)
+	}
+	if a := errorListInternal(errList).Error(); a != "" {
+		t.Errorf("expected empty string, got %q", a)
+	}
+
+	testCases := []struct {
+		errs     ErrorList
+		expected string
+	}{
+		{ErrorList{fmt.Errorf("abc")}, "abc"},
+		{ErrorList{fmt.Errorf("abc"), fmt.Errorf("123")}, "[abc, 123]"},
+	}
+	for _, testCase := range testCases {
+		err := testCase.errs.ToError()
+		if err == nil {
+			t.Errorf("expected an error, got nil: %v", testCase)
+			continue
+		}
+		if err.Error() != testCase.expected {
+			t.Errorf("expected %q, got %q", testCase.expected, err.Error())
+		}
+	}
+}