Added completion for revision resource (#1560)

* Added completion for revision resource

* Added unit tests for revision autocompletion

* Fixed merge conflicts

pkg/kn/commands/completion_helper.go

@@ -29,8 +29,9 @@ type completionConfig struct {
 
 var (
 	resourceToFuncMap = map[string]func(config *completionConfig) []string{
-		"broker":  completeBroker,
-		"service": completeService,
+		"service":  completeService,
+		"revision": completeRevision,
+		"broker":   completeBroker,
 	}
 )
 
@@ -150,3 +151,29 @@ func completeBroker(config *completionConfig) (suggestions []string) {
 	}
 	return
 }
+
+func completeRevision(config *completionConfig) (suggestions []string) {
+	suggestions = make([]string, 0)
+	if len(config.args) != 0 {
+		return
+	}
+	namespace, err := config.params.GetNamespace(config.command)
+	if err != nil {
+		return
+	}
+	client, err := config.params.NewServingClient(namespace)
+	if err != nil {
+		return
+	}
+	revisionList, err := client.ListRevisions(config.command.Context())
+	if err != nil {
+		return
+	}
+	for _, sug := range revisionList.Items {
+		if !strings.HasPrefix(sug.Name, config.toComplete) {
+			continue
+		}
+		suggestions = append(suggestions, sug.Name)
+	}
+	return
+}

pkg/kn/commands/completion_helper_test.go

@@ -120,6 +120,31 @@ func initialiseKnParams() *KnParams {
 	}
 }
 
+var (
+	testRev1 = servingv1.Revision{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Revision",
+			APIVersion: "serving.knative.dev/v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{Name: "test-rev-1", Namespace: testNs},
+	}
+	testRev2 = servingv1.Revision{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Revision",
+			APIVersion: "serving.knative.dev/v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{Name: "test-rev-2", Namespace: testNs},
+	}
+	testRev3 = servingv1.Revision{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Revision",
+			APIVersion: "serving.knative.dev/v1",
+		},
+		ObjectMeta: metav1.ObjectMeta{Name: "test-rev-3", Namespace: testNs},
+	}
+	testNsRevs = []servingv1.Revision{testRev1, testRev2, testRev3}
+)
+
 func TestResourceNameCompletionFuncService(t *testing.T) {
 	completionFunc := ResourceNameCompletionFunc(knParams)
 
@@ -283,6 +308,84 @@ func TestResourceNameCompletionFuncBroker(t *testing.T) {
 	}
 }
 
+func TestResourceNameCompletionFuncRevision(t *testing.T) {
+	completionFunc := ResourceNameCompletionFunc(knParams)
+
+	fakeServing.AddReactor("list", "revisions",
+		func(a clienttesting.Action) (bool, runtime.Object, error) {
+			if a.GetNamespace() == errorNs {
+				return true, nil, errors.NewInternalError(fmt.Errorf("unable to list revisions"))
+			}
+			return true, &servingv1.RevisionList{Items: testNsRevs}, nil
+		})
+
+	tests := []testType{
+		{
+			"Empty suggestions when non-zero args",
+			testNs,
+			knParams,
+			[]string{"xyz"},
+			"",
+			"revision",
+		},
+		{
+			"Empty suggestions when no namespace flag",
+			"",
+			knParams,
+			nil,
+			"",
+			"revision",
+		},
+		{
+			"Suggestions when test-ns namespace set",
+			testNs,
+			knParams,
+			nil,
+			"",
+			"revision",
+		},
+		{
+			"Empty suggestions when toComplete is not a prefix",
+			testNs,
+			knParams,
+			nil,
+			"xyz",
+			"revision",
+		},
+		{
+			"Empty suggestions when error during list operation",
+			errorNs,
+			knParams,
+			nil,
+			"",
+			"revision",
+		},
+	}
+	for _, tt := range tests {
+		cmd := getResourceCommandWithTestSubcommand(tt.resource, tt.namespace != "", tt.resource != "no-parent")
+		t.Run(tt.name, func(t *testing.T) {
+			config := &completionConfig{
+				params:     tt.p,
+				command:    cmd,
+				args:       tt.args,
+				toComplete: tt.toComplete,
+			}
+			expectedFunc := resourceToFuncMap[tt.resource]
+			if expectedFunc == nil {
+				expectedFunc = func(config *completionConfig) []string {
+					return []string{}
+				}
+			}
+			cmd.Flags().Set("namespace", tt.namespace)
+			actualSuggestions, actualDirective := completionFunc(cmd, tt.args, tt.toComplete)
+			expectedSuggestions := expectedFunc(config)
+			expectedDirective := cobra.ShellCompDirectiveNoFileComp
+			assert.DeepEqual(t, actualSuggestions, expectedSuggestions)
+			assert.Equal(t, actualDirective, expectedDirective)
+		})
+	}
+}
+
 func TestResourceNameCompletionFuncGitOps(t *testing.T) {
 	tempDir := setupTempDir(t)
 	assert.Assert(t, tempDir != "")

pkg/kn/commands/revision/delete.go

@@ -45,6 +45,7 @@ func NewRevisionDeleteCommand(p *commands.KnParams) *cobra.Command {
 
   # Delete all unreferenced revisions for a given service 'mysvc'
   kn revision delete --prune mysvc`,
+		ValidArgsFunction: commands.ResourceNameCompletionFunc(p),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			prune := cmd.Flags().Changed("prune")
 			argsLen := len(args)

pkg/kn/commands/revision/describe.go

@@ -42,8 +42,9 @@ func NewRevisionDescribeCommand(p *commands.KnParams) *cobra.Command {
 	machineReadablePrintFlags := genericclioptions.NewPrintFlags("")
 
 	command := &cobra.Command{
-		Use:   "describe NAME",
-		Short: "Show details of a revision",
+		Use:               "describe NAME",
+		Short:             "Show details of a revision",
+		ValidArgsFunction: commands.ResourceNameCompletionFunc(p),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			if len(args) != 1 {
 				return errors.New("'kn revision describe' requires name of the revision as single argument")