use fake filesystem to test key file flag for ark restic init-repo

Signed-off-by: Steve Kriss <steve@heptio.com>

pkg/cmd/cli/restic/init_repository.go

@@ -18,11 +18,11 @@ package restic
 
 import (
 	"crypto/rand"
-	"io/ioutil"
 
 	"github.com/heptio/ark/pkg/client"
 	"github.com/heptio/ark/pkg/cmd"
 	"github.com/heptio/ark/pkg/restic"
+	"github.com/heptio/ark/pkg/util/filesystem"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -55,13 +55,15 @@ type InitRepositoryOptions struct {
 	KeyData   string
 	KeySize   int
 
+	fileSystem filesystem.Interface
 	kubeClient kclientset.Interface
 	keyBytes   []byte
 }
 
 func NewInitRepositoryOptions() *InitRepositoryOptions {
 	return &InitRepositoryOptions{
-		KeySize: 1024,
+		KeySize:    1024,
+		fileSystem: filesystem.NewFileSystem(),
 	}
 }
 
@@ -89,7 +91,7 @@ func (o *InitRepositoryOptions) Complete(f client.Factory) error {
 
 	switch {
 	case o.KeyFile != "":
-		data, err := ioutil.ReadFile(o.KeyFile)
+		data, err := o.fileSystem.ReadFile(o.KeyFile)
 		if err != nil {
 			return err
 		}

pkg/cmd/cli/restic/init_repository_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/heptio/ark/pkg/client"
 	clientset "github.com/heptio/ark/pkg/generated/clientset/versioned"
+	arktest "github.com/heptio/ark/pkg/util/test"
 )
 
 type fakeFactory struct{}
@@ -46,10 +47,14 @@ func TestComplete(t *testing.T) {
 	err = o.Complete(&fakeFactory{})
 	assert.EqualError(t, err, errKeyFileAndKeyDataProvided.Error())
 
-	// TODO test that if KeyFile is provided, the data is used
-	// (should move the pkg/restore/FileSystem interface to
-	// a common location and use it here so ioutil.ReadFile
-	// can be easily mocked)
+	// if KeyFile is provided, its contents are used
+	fileContents := []byte("bar")
+	o = &InitRepositoryOptions{
+		KeyFile:    "/foo",
+		fileSystem: arktest.NewFakeFileSystem().WithFile("/foo", fileContents),
+	}
+	assert.NoError(t, o.Complete(&fakeFactory{}))
+	assert.Equal(t, fileContents, o.keyBytes)
 
 	// if KeyData is provided, it's used
 	o = &InitRepositoryOptions{