Adds zsh completion (#476)

* Adds zsh completion

 - Adds back zsh completion after vendoring cobra library with a fix
 - Updates the command definition to accept argument either of ['bash', 'zsh']
 - Moves the completion command definition under `pkg/kn/commands/completion`
 - Updates docs
 - Updates CHANGELOG.adoc

* fix(golint): exported function should have comment

* Fixes PR number in CHANGELOG.adoc

* Updates unit tests

CHANGELOG.adoc

@@ -12,6 +12,22 @@
 |===
 ////
 
+## v0.10.0 (2019-11-05)
+
+[cols="1,10,3", options="header", width="100%"]
+|===
+| | Description | PR
+
+| 🧽
+| Update to Knative serving dependency to 0.10.0
+| https://github.com/knative/client/pull/474[#474]
+
+| 🎁
+| Adds zsh completion
+| https://github.com/knative/client/pull/476[#476]
+
+|===
+
 ## v0.9.0 (2019-10-29)
 
 [cols="1,10,3", options="header", width="100%"]

README.md

@@ -17,24 +17,22 @@ Start with the [user's guide](docs/README.md) to learn more. You can read about
 * [User's guide](docs/README.md)
 * [Generated documentation](docs/cmd/kn.md)
 
-**Bash auto completion:**
+**Shell auto completion:**
 
-Run the following command to enable BASH auto-completion:
+Run the following command to enable shell auto-completion:
 
+For Zsh:
 ```sh
-$ source <(kn completion)
+$ source <(kn completion zsh)
 ```
 
-Use TAB to list available sub-commands:
-
+For Bash:
 ```sh
-$ kn <TAB>
-completion revision service version
-
-$ kn revision <TAB>
-describe get
+$ source <(kn completion bash)
 ```
 
+Use TAB to list available sub-commands or flags.
+
 # Developers
 
 If you would like to contribute, please see

pkg/kn/commands/completion/completion.go

@@ -0,0 +1,66 @@
+// Copyright © 2019 The Knative Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package completion
+
+import (
+	"fmt"
+	"os"
+
+	"knative.dev/client/pkg/kn/commands"
+
+	"github.com/spf13/cobra"
+)
+
+const (
+	desc = `
+This command prints shell completion code which need to be evaluated
+to provide interactive completion
+
+Supported Shells:
+ - bash
+ - zsh`
+	eg = `
+ # Generate completion code for bash
+ source <(kn completion bash)
+
+ # Generate completion code for zsh
+ source <(kn completion zsh)`
+)
+
+// NewCompletionCommand implements shell auto-completion feature for Bash and Zsh
+func NewCompletionCommand(p *commands.KnParams) *cobra.Command {
+	return &cobra.Command{
+		Use:       "completion [SHELL]",
+		Short:     "Output shell completion code",
+		Long:      desc,
+		ValidArgs: []string{"bash", "zsh"},
+		Example:   eg,
+		Hidden:    true, // Don't show this in help listing
+		Run: func(cmd *cobra.Command, args []string) {
+			if len(args) == 1 {
+				switch args[0] {
+				case "bash":
+					cmd.Root().GenBashCompletion(os.Stdout)
+				case "zsh":
+					cmd.Root().GenZshCompletion(os.Stdout)
+				default:
+					fmt.Println("only supports 'bash' or 'zsh' shell completion")
+				}
+			} else {
+				fmt.Println("accepts one argument either 'bash' or 'zsh'")
+			}
+		},
+	}
+}

pkg/kn/commands/completion_test.go → pkg/kn/commands/completion/completion_test.go

@@ -12,23 +12,25 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package commands
+package completion
 
 import (
 	"testing"
 
+	"knative.dev/client/pkg/kn/commands"
+
 	"github.com/spf13/cobra"
 	"gotest.tools/assert"
 )
 
 func TestCompletion(t *testing.T) {
 	var (
 		fakeRootCmd, completionCmd *cobra.Command
-		knParams                   *KnParams
+		knParams                   *commands.KnParams
 	)
 
 	setup := func() {
-		knParams = &KnParams{}
+		knParams = &commands.KnParams{}
 		completionCmd = NewCompletionCommand(knParams)
 
 		fakeRootCmd = &cobra.Command{}
@@ -37,17 +39,44 @@ func TestCompletion(t *testing.T) {
 
 	t.Run("creates a CompletionCommand", func(t *testing.T) {
 		setup()
-		assert.Equal(t, completionCmd.Use, "completion")
-		assert.Equal(t, completionCmd.Short, "Output shell completion code (Bash)")
+		assert.Equal(t, completionCmd.Use, "completion [SHELL]")
+		assert.Equal(t, completionCmd.Short, "Output shell completion code")
 		assert.Assert(t, completionCmd.RunE == nil)
 	})
 
 	t.Run("returns completion code for BASH", func(t *testing.T) {
 		setup()
-		CaptureStdout(t)
-		defer ReleaseStdout(t)
+		commands.CaptureStdout(t)
+		defer commands.ReleaseStdout(t)
+
+		completionCmd.Run(fakeRootCmd, []string{"bash"})
+		assert.Assert(t, commands.ReadStdout(t) != "")
+	})
+
+	t.Run("returns completion code for Zsh", func(t *testing.T) {
+		setup()
+		commands.CaptureStdout(t)
+		defer commands.ReleaseStdout(t)
+
+		completionCmd.Run(fakeRootCmd, []string{"zsh"})
+		assert.Assert(t, commands.ReadStdout(t) != "")
+	})
+
+	t.Run("returns error on command without args", func(t *testing.T) {
+		setup()
+		commands.CaptureStdout(t)
+		defer commands.ReleaseStdout(t)
 
 		completionCmd.Run(fakeRootCmd, []string{})
-		assert.Assert(t, ReadStdout(t) != "")
+		assert.Assert(t, commands.ReadStdout(t) == "accepts one argument either 'bash' or 'zsh'\n")
+	})
+
+	t.Run("returns error on command with invalid args", func(t *testing.T) {
+		setup()
+		commands.CaptureStdout(t)
+		defer commands.ReleaseStdout(t)
+
+		completionCmd.Run(fakeRootCmd, []string{"sh"})
+		assert.Assert(t, commands.ReadStdout(t) == "only supports 'bash' or 'zsh' shell completion\n")
 	})
 }

pkg/kn/core/root.go

@@ -30,6 +30,7 @@ import (
 	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/oidc"
 	"knative.dev/client/pkg/kn/commands"
+	"knative.dev/client/pkg/kn/commands/completion"
 	"knative.dev/client/pkg/kn/commands/plugin"
 	"knative.dev/client/pkg/kn/commands/revision"
 	"knative.dev/client/pkg/kn/commands/route"
@@ -139,7 +140,7 @@ func NewKnCommand(params ...commands.KnParams) *cobra.Command {
 	rootCmd.AddCommand(revision.NewRevisionCommand(p))
 	rootCmd.AddCommand(plugin.NewPluginCommand(p))
 	rootCmd.AddCommand(route.NewRouteCommand(p))
-	rootCmd.AddCommand(commands.NewCompletionCommand(p))
+	rootCmd.AddCommand(completion.NewCompletionCommand(p))
 	rootCmd.AddCommand(version.NewVersionCommand(p))
 
 	// Deal with empty and unknown sub command groups