issue #104: add version command

cmd/retry/completion_test.go

@@ -6,26 +6,31 @@ import (
 	"bytes"
 	"testing"
 
+	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestCompletion(t *testing.T) {
 	before := Completion.OutOrStdout()
 	defer Completion.SetOutput(before)
 
+	buf := bytes.NewBuffer(nil)
+	cmd := &cobra.Command{Use: "test"}
+	cmd.AddCommand(Completion)
+	cmd.SetOutput(buf)
+
 	tests := []struct {
 		name     string
 		format   string
 		expected string
 	}{
-		{"Bash", "bash", "# bash completion for completion"},
-		{"Zsh", "zsh", "#compdef completion"},
+		{"Bash", "bash", "# bash completion for test"},
+		{"Zsh", "zsh", "#compdef test"},
 	}
 	for _, test := range tests {
 		tc := test
 		t.Run(test.name, func(t *testing.T) {
-			buf := bytes.NewBuffer(nil)
-			Completion.SetOutput(buf)
+			buf.Reset()
 			Completion.Flag("format").Value.Set(tc.format)
 			assert.NoError(t, Completion.RunE(Completion, nil))
 			assert.Contains(t, buf.String(), tc.expected)

cmd/retry/version.go

@@ -0,0 +1,27 @@
+// +build go1.10
+
+package main
+
+import (
+	"runtime"
+
+	"github.com/spf13/cobra"
+)
+
+var (
+	commit  = "none"
+	date    = "unknown"
+	version = "dev"
+)
+
+// Version shows application version.
+var Version = &cobra.Command{
+	Use:   "version",
+	Short: "Show application version",
+	Run: func(cmd *cobra.Command, args []string) {
+		cmd.Printf(
+			"Version %s (commit: %s, build date: %s, go version: %s, compiler: %s, platform: %s/%s)\n",
+			version, commit, date, runtime.Version(), runtime.Compiler, runtime.GOOS, runtime.GOARCH)
+	},
+	Version: version,
+}

cmd/retry/version_test.go

@@ -0,0 +1,45 @@
+// +build go1.10
+
+package main
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestVersion(t *testing.T) {
+	type memo struct {
+		commit  string
+		date    string
+		version string
+	}
+
+	buf := bytes.NewBuffer(nil)
+	cmd := &cobra.Command{Use: "test"}
+	cmd.AddCommand(Version)
+	cmd.SetOutput(buf)
+
+	tests := []struct {
+		name string
+		memo
+		expected string
+	}{
+		{"Version 4.0", memo{commit: "0c2ffff", date: "November 30, 2018", version: "4.0.0"},
+			"Version 4.0.0 (commit: 0c2ffff, build date: November 30, 2018"},
+	}
+	for _, test := range tests {
+		tc := test
+		t.Run(test.name, func(t *testing.T) {
+			before := memo{commit: commit, date: date, version: version}
+			defer func() { commit, date, version = before.commit, before.date, before.version }()
+			commit, date, version = tc.commit, tc.date, tc.version
+
+			buf.Reset()
+			Version.Run(Version, nil)
+			assert.Contains(t, buf.String(), tc.expected)
+		})
+	}
+}