golang.org/x/tools@v0.21.0/internal/diffp/diff_test.go (about)

     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  
     5  package diffp
     6  
     7  import (
     8  	"bytes"
     9  	"path/filepath"
    10  	"testing"
    11  
    12  	"golang.org/x/tools/txtar"
    13  )
    14  
    15  func clean(text []byte) []byte {
    16  	text = bytes.ReplaceAll(text, []byte("$\n"), []byte("\n"))
    17  	text = bytes.TrimSuffix(text, []byte("^D\n"))
    18  	return text
    19  }
    20  
    21  func Test(t *testing.T) {
    22  	files, _ := filepath.Glob("testdata/*.txt")
    23  	if len(files) == 0 {
    24  		t.Fatalf("no testdata")
    25  	}
    26  
    27  	for _, file := range files {
    28  		t.Run(filepath.Base(file), func(t *testing.T) {
    29  			a, err := txtar.ParseFile(file)
    30  			if err != nil {
    31  				t.Fatal(err)
    32  			}
    33  			if len(a.Files) != 3 || a.Files[2].Name != "diff" {
    34  				t.Fatalf("%s: want three files, third named \"diff\"", file)
    35  			}
    36  			diffs := Diff(a.Files[0].Name, clean(a.Files[0].Data), a.Files[1].Name, clean(a.Files[1].Data))
    37  			want := clean(a.Files[2].Data)
    38  			if !bytes.Equal(diffs, want) {
    39  				t.Fatalf("%s: have:\n%s\nwant:\n%s\n%s", file,
    40  					diffs, want, Diff("have", diffs, "want", want))
    41  			}
    42  		})
    43  	}
    44  }