github.com/hairyhenderson/gomplate/v4@v4.0.0-pre-2.0.20240520121557-362f058f0c93/internal/datafs/getenv_test.go (about)

     1  package datafs
     2  
     3  import (
     4  	"errors"
     5  	"io/fs"
     6  	"testing"
     7  	"testing/fstest"
     8  
     9  	"github.com/hack-pad/hackpadfs"
    10  
    11  	"github.com/stretchr/testify/assert"
    12  )
    13  
    14  func TestGetenvFsys(t *testing.T) {
    15  	fsys := fs.FS(fstest.MapFS{
    16  		"tmp":            &fstest.MapFile{Mode: fs.ModeDir | 0o777},
    17  		"tmp/foo":        &fstest.MapFile{Data: []byte("foo")},
    18  		"tmp/unreadable": &fstest.MapFile{Data: []byte("foo"), Mode: 0o000},
    19  	})
    20  	fsys = WrapWdFS(fsys)
    21  
    22  	t.Setenv("FOO_FILE", "/tmp/foo")
    23  	assert.Equal(t, "foo", GetenvFsys(fsys, "FOO", "bar"))
    24  
    25  	t.Setenv("FOO_FILE", "/tmp/missing")
    26  	assert.Equal(t, "bar", GetenvFsys(fsys, "FOO", "bar"))
    27  
    28  	fsys = writeOnly(fsys)
    29  	t.Setenv("FOO_FILE", "/tmp/unreadable")
    30  	assert.Equal(t, "bar", GetenvFsys(fsys, "FOO", "bar"))
    31  }
    32  
    33  func TestExpandEnvFsys(t *testing.T) {
    34  	fsys := fs.FS(fstest.MapFS{
    35  		"tmp":            &fstest.MapFile{Mode: fs.ModeDir | 0o777},
    36  		"tmp/foo":        &fstest.MapFile{Data: []byte("foo")},
    37  		"tmp/unreadable": &fstest.MapFile{Data: []byte("foo"), Mode: 0o000},
    38  	})
    39  	fsys = WrapWdFS(fsys)
    40  
    41  	t.Setenv("FOO_FILE", "/tmp/foo")
    42  	assert.Equal(t, "foo is foo", ExpandEnvFsys(fsys, "foo is $FOO"))
    43  
    44  	t.Setenv("FOO_FILE", "/tmp/missing")
    45  	assert.Equal(t, "empty", ExpandEnvFsys(fsys, "${FOO}empty"))
    46  
    47  	fsys = writeOnly(fsys)
    48  	t.Setenv("FOO_FILE", "/tmp/unreadable")
    49  	assert.Equal(t, "", ExpandEnvFsys(fsys, "${FOO}"))
    50  }
    51  
    52  // Maybe extract this into a separate package sometime...
    53  // writeOnly - represents a filesystem that's writeable, but read operations fail
    54  func writeOnly(fsys fs.FS) fs.FS {
    55  	return &woFS{fsys}
    56  }
    57  
    58  type woFS struct {
    59  	fsys fs.FS
    60  }
    61  
    62  func (fsys woFS) Open(name string) (fs.File, error) {
    63  	f, err := fsys.fsys.Open(name)
    64  	return writeOnlyFile(f), err
    65  }
    66  
    67  func (fsys woFS) ReadDir(_ string) ([]fs.DirEntry, error) {
    68  	return nil, ErrWriteOnly
    69  }
    70  
    71  func (fsys woFS) Stat(_ string) (fs.FileInfo, error) {
    72  	return nil, ErrWriteOnly
    73  }
    74  
    75  func writeOnlyFile(f fs.File) fs.File {
    76  	if f == nil {
    77  		return nil
    78  	}
    79  
    80  	return &woFile{f}
    81  }
    82  
    83  type woFile struct {
    84  	fs.File
    85  }
    86  
    87  // Write -
    88  func (f woFile) Write(p []byte) (n int, err error) {
    89  	return hackpadfs.WriteFile(f.File, p)
    90  }
    91  
    92  // Read is disabled and returns ErrWriteOnly
    93  func (f woFile) Read([]byte) (n int, err error) {
    94  	return 0, ErrWriteOnly
    95  }
    96  
    97  var ErrWriteOnly = errors.New("filesystem is write-only")