1// Copyright 2022 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package diff
6
7import (
8	"bytes"
9	"internal/txtar"
10	"path/filepath"
11	"testing"
12)
13
14func clean(text []byte) []byte {
15	text = bytes.ReplaceAll(text, []byte("$\n"), []byte("\n"))
16	text = bytes.TrimSuffix(text, []byte("^D\n"))
17	return text
18}
19
20func Test(t *testing.T) {
21	files, _ := filepath.Glob("testdata/*.txt")
22	if len(files) == 0 {
23		t.Fatalf("no testdata")
24	}
25
26	for _, file := range files {
27		t.Run(filepath.Base(file), func(t *testing.T) {
28			a, err := txtar.ParseFile(file)
29			if err != nil {
30				t.Fatal(err)
31			}
32			if len(a.Files) != 3 || a.Files[2].Name != "diff" {
33				t.Fatalf("%s: want three files, third named \"diff\"", file)
34			}
35			diffs := Diff(a.Files[0].Name, clean(a.Files[0].Data), a.Files[1].Name, clean(a.Files[1].Data))
36			want := clean(a.Files[2].Data)
37			if !bytes.Equal(diffs, want) {
38				t.Fatalf("%s: have:\n%s\nwant:\n%s\n%s", file,
39					diffs, want, Diff("have", diffs, "want", want))
40			}
41		})
42	}
43}
44