|  | // Copyright 2018 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 main | 
|  |  | 
|  | import ( | 
|  | "bytes" | 
|  | "strconv" | 
|  | "testing" | 
|  | ) | 
|  |  | 
|  | func TestCopyAndInject(t *testing.T) { | 
|  | s := "abcdefghijklmnopqrstuvwxyz" | 
|  | testCases := []struct { | 
|  | offset, size uint64 | 
|  | value        string | 
|  | expected     string | 
|  | }{ | 
|  | { | 
|  | offset:   0, | 
|  | size:     1, | 
|  | value:    "A", | 
|  | expected: "Abcdefghijklmnopqrstuvwxyz", | 
|  | }, | 
|  | { | 
|  | offset:   1, | 
|  | size:     1, | 
|  | value:    "B", | 
|  | expected: "aBcdefghijklmnopqrstuvwxyz", | 
|  | }, | 
|  | { | 
|  | offset:   1, | 
|  | size:     1, | 
|  | value:    "BCD", | 
|  | expected: "aBcdefghijklmnopqrstuvwxyz", | 
|  | }, | 
|  | { | 
|  | offset:   25, | 
|  | size:     1, | 
|  | value:    "Z", | 
|  | expected: "abcdefghijklmnopqrstuvwxyZ", | 
|  | }, | 
|  | } | 
|  |  | 
|  | for i, testCase := range testCases { | 
|  | t.Run(strconv.Itoa(i), func(t *testing.T) { | 
|  | in := bytes.NewReader([]byte(s)) | 
|  | out := &bytes.Buffer{} | 
|  | copyAndInject(in, out, testCase.offset, testCase.size, testCase.value) | 
|  |  | 
|  | if out.String() != testCase.expected { | 
|  | t.Errorf("expected %s, got %s", testCase.expected, out.String()) | 
|  | } | 
|  | }) | 
|  | } | 
|  | } |