wip tests

internal/cmd/cmd.go

@@ -7,9 +7,9 @@ import (
 
 // BaseCommand provides common fields to all commands.
 type BaseCommand struct {
-	Stdin  io.ReadCloser
-	Stdout io.WriteCloser
-	Stderr io.WriteCloser
+	Stdin  io.Reader
+	Stdout io.Writer
+	Stderr io.Writer
 }
 
 // Init initializes BaseCommand with default arguments

internal/cmdrootfs/BUILD

@@ -9,7 +9,6 @@ go_library(
         "//src/undocker/internal/cmd:go_default_library",
         "//src/undocker/rootfs:go_default_library",
         "@com_github_jessevdk_go_flags//:go_default_library",
-        "@com_github_ulikunitz_xz//:go_default_library",
         "@org_uber_go_multierr//:go_default_library",
     ],
 )
@@ -18,4 +17,10 @@ go_test(
     name = "go_default_test",
     srcs = ["cmdrootfs_test.go"],
     embed = [":go_default_library"],
+    deps = [
+        "//src/undocker/internal/cmd:go_default_library",
+        "@com_github_jessevdk_go_flags//:go_default_library",
+        "@com_github_stretchr_testify//assert:go_default_library",
+        "@com_github_stretchr_testify//require:go_default_library",
+    ],
 )

internal/cmdrootfs/cmdrootfs.go

@@ -2,29 +2,31 @@ package cmdrootfs
 
 import (
 	"errors"
+	"fmt"
 	"io"
 	"os"
 
 	goflags "github.com/jessevdk/go-flags"
 	"github.com/motiejus/code/undocker/internal/cmd"
 	"github.com/motiejus/code/undocker/rootfs"
-	"github.com/ulikunitz/xz"
 	"go.uber.org/multierr"
 )
 
-// Command is "rootfs" command
-type Command struct {
-	cmd.BaseCommand
+type (
+	rootfsFactory func(io.ReadSeeker) io.WriterTo
 
-	PositionalArgs struct {
-		Infile  goflags.Filename `long:"infile" description:"Input tarball"`
-		Outfile string           `long:"outfile" description:"Output path, stdout is '-'"`
-	} `positional-args:"yes" required:"yes"`
+	// Command is "rootfs" command
+	Command struct {
+		cmd.BaseCommand
 
-	Xz bool `short:"J" long:"xz" description:"create XZ archive"`
+		PositionalArgs struct {
+			Infile  goflags.Filename `long:"infile" description:"Input tarball"`
+			Outfile string           `long:"outfile" description:"Output path, stdout is '-'"`
+		} `positional-args:"yes" required:"yes"`
 
-	rootfsNew func(io.ReadSeeker) io.WriterTo
-}
+		rootfsNew rootfsFactory
+	}
+)
 
 // Execute executes rootfs Command
 func (c *Command) Execute(args []string) (err error) {
@@ -42,25 +44,15 @@ func (c *Command) Execute(args []string) (err error) {
 	defer func() { err = multierr.Append(err, rd.Close()) }()
 
 	var out io.Writer
-	var outf *os.File
 	if fname := string(c.PositionalArgs.Outfile); fname == "-" {
-		outf = os.Stdout
+		out = c.Stdout
 	} else {
-		outf, err = os.Create(fname)
+		outf, err := os.Create(fname)
 		if err != nil {
-			return err
+			return fmt.Errorf("create: %w", err)
 		}
-	}
-	out = outf
-	defer func() { err = multierr.Append(err, outf.Close()) }()
-
-	if c.Xz {
-		outz, err := xz.NewWriter(out)
-		if err != nil {
-			return err
-		}
-		defer func() { err = multierr.Append(err, outz.Close()) }()
-		out = outz
+		defer func() { err = multierr.Append(err, outf.Close()) }()
+		out = outf
 	}
 
 	if _, err := c.rootfsNew(rd).WriteTo(out); err != nil {

internal/cmdrootfs/cmdrootfs_test.go

@@ -1,6 +1,73 @@
 package cmdrootfs
 
-import "testing"
+import (
+	"bytes"
+	"io"
+	"path/filepath"
+	"testing"
+
+	goflags "github.com/jessevdk/go-flags"
+	"github.com/motiejus/code/undocker/internal/cmd"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
 
 func TestExecute(t *testing.T) {
+	dir := t.TempDir()
+
+	tests := []struct {
+		name    string
+		in      []byte
+		infile  string
+		outfile string
+		want    []byte
+		wantErr string
+	}{
+		{
+			name:    "ok passthrough via stdout",
+			in:      []byte("foo"),
+			outfile: "-",
+			want:    []byte("foo"),
+		},
+		{
+			name:    "ok passthrough via file",
+			in:      []byte("foo"),
+			outfile: filepath.Join(dir, "t1.txt"),
+			want:    []byte("foo"),
+		},
+		{
+			name:    "infile does not exist",
+			infile:  filepath.Join(dir, "does", "not", "exist"),
+			wantErr: "open <...>/does/not/exist: enoent",
+		},
+		{
+			name:    "outpath dir not writable",
+			outfile: filepath.Join(dir, "does", "not", "exist"),
+			wantErr: "create: stat <...>/does/not/exist: enoent",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var stdout bytes.Buffer
+			c := &Command{BaseCommand: cmd.BaseCommand{Stdout: &stdout}}
+			c.PositionalArgs.Infile = goflags.Filename(tt.infile)
+			c.PositionalArgs.Outfile = tt.outfile
+			c.rootfsNew = func(r io.ReadSeeker) io.WriterTo {
+				return &passthrough{r}
+			}
+
+			err := c.Execute(nil)
+			if tt.wantErr != "" {
+				assert.EqualError(t, err, tt.wantErr)
+				return
+			}
+			require.NoError(t, err)
+			assert.Equal(t, tt.want, stdout.Bytes())
+		})
+	}
 }
+
+type passthrough struct{ r io.Reader }
+
+func (p *passthrough) WriteTo(w io.Writer) (int64, error) { return io.Copy(w, p.r) }