MM-11905: delete plugin commands on removal (#9601)

* defer plugin tear down for testing

* test expected plugin command unregistration

* MM-11905: uninstall plugin commands on remove

app/plugin_commands_test.go

@@ -0,0 +1,104 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package app
+
+import (
+	"testing"
+
+	"github.com/mattermost/mattermost-server/model"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPluginCommand(t *testing.T) {
+	th := Setup().InitBasic()
+	defer th.TearDown()
+
+	args := &model.CommandArgs{}
+	args.TeamId = th.BasicTeam.Id
+	args.ChannelId = th.BasicChannel.Id
+	args.UserId = th.BasicUser.Id
+	args.Command = "/plugin"
+
+	t.Run("error before plugin command registered", func(t *testing.T) {
+		_, err := th.App.ExecuteCommand(args)
+		require.NotNil(t, err)
+	})
+
+	t.Run("command handled by plugin", func(t *testing.T) {
+		th.App.UpdateConfig(func(cfg *model.Config) {
+			cfg.PluginSettings.Plugins["testloadpluginconfig"] = map[string]interface{}{
+				"TeamId": args.TeamId,
+			}
+		})
+
+		tearDown, pluginIds, activationErrors := SetAppEnvironmentWithPlugins(t, []string{`
+			package main
+
+			import (
+				"github.com/mattermost/mattermost-server/plugin"
+				"github.com/mattermost/mattermost-server/model"
+			)
+
+			type configuration struct {
+				TeamId string
+			}
+
+			type MyPlugin struct {
+				plugin.MattermostPlugin	
+
+				configuration configuration
+			}
+
+			func (p *MyPlugin) OnConfigurationChange() error {
+				p.API.LogError("hello")
+				if err := p.API.LoadPluginConfiguration(&p.configuration); err != nil {
+					return err
+				}
+
+				return nil
+			}
+
+			func (p *MyPlugin) OnActivate() error {
+				p.API.LogError("team", "team", p.configuration.TeamId)
+				err := p.API.RegisterCommand(&model.Command{
+					TeamId: p.configuration.TeamId,
+					Trigger: "plugin",
+					DisplayName: "Plugin Command",
+				})
+				if err != nil {
+					p.API.LogError("error", "err", err)
+				}
+				p.API.LogDebug("team", "team", p.configuration.TeamId)
+
+				return err
+			}
+
+			func (p *MyPlugin) ExecuteCommand(c *plugin.Context, args *model.CommandArgs) (*model.CommandResponse, *model.AppError) {
+				return &model.CommandResponse{
+					ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+					Text: "text",
+				}, nil
+			}
+
+			func main() {
+				plugin.ClientMain(&MyPlugin{})
+			}
+		`}, th.App, th.App.NewPluginAPI)
+		defer tearDown()
+		require.Len(t, activationErrors, 1)
+		require.Nil(t, nil, activationErrors[0])
+
+		resp, err := th.App.ExecuteCommand(args)
+		require.Nil(t, err)
+		require.Equal(t, model.COMMAND_RESPONSE_TYPE_EPHEMERAL, resp.ResponseType)
+		require.Equal(t, "text", resp.Text)
+
+		th.App.RemovePlugin(pluginIds[0])
+	})
+
+	t.Run("error after plugin command unregistered", func(t *testing.T) {
+		_, err := th.App.ExecuteCommand(args)
+		require.NotNil(t, err)
+	})
+}