PLT-7111 Add groupmsg command (#7419)

* Coping command_msg to use as command_groupmsg base

* Changing msg to groupmsg names in groumsg command

* Add groupmsg command

api/command_groupmsg_test.go

@@ -0,0 +1,58 @@
+// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package api
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/mattermost/mattermost-server/model"
+)
+
+func TestGroupmsgCommands(t *testing.T) {
+	th := Setup().InitBasic()
+	defer th.TearDown()
+
+	Client := th.BasicClient
+	team := th.BasicTeam
+	user1 := th.BasicUser
+	user2 := th.BasicUser2
+	user3 := th.CreateUser(th.BasicClient)
+	user4 := th.CreateUser(th.BasicClient)
+	user5 := th.CreateUser(th.BasicClient)
+	user6 := th.CreateUser(th.BasicClient)
+	user7 := th.CreateUser(th.BasicClient)
+	user8 := th.CreateUser(th.BasicClient)
+	user9 := th.CreateUser(th.BasicClient)
+	th.LinkUserToTeam(user3, team)
+	th.LinkUserToTeam(user4, team)
+
+	rs1 := Client.Must(Client.Command("", "/groupmsg "+user2.Username+","+user3.Username)).Data.(*model.CommandResponse)
+
+	group1 := model.GetGroupNameFromUserIds([]string{user1.Id, user2.Id, user3.Id})
+
+	if !strings.HasSuffix(rs1.GotoLocation, "/"+team.Name+"/channels/"+group1) {
+		t.Fatal("failed to create group channel")
+	}
+
+	rs2 := Client.Must(Client.Command("", "/groupmsg "+user3.Username+","+user4.Username+" foobar")).Data.(*model.CommandResponse)
+	group2 := model.GetGroupNameFromUserIds([]string{user1.Id, user3.Id, user4.Id})
+
+	if !strings.HasSuffix(rs2.GotoLocation, "/"+team.Name+"/channels/"+group2) {
+		t.Fatal("failed to create second direct channel")
+	}
+	if result := Client.Must(Client.SearchPosts("foobar", false)).Data.(*model.PostList); len(result.Order) == 0 {
+		t.Fatal("post did not get sent to direct message")
+	}
+
+	rs3 := Client.Must(Client.Command("", "/groupmsg "+user2.Username+","+user3.Username)).Data.(*model.CommandResponse)
+	if !strings.HasSuffix(rs3.GotoLocation, "/"+team.Name+"/channels/"+group1) {
+		t.Fatal("failed to go back to existing group channel")
+	}
+
+	Client.Must(Client.Command("", "/groupmsg "+user2.Username+" foobar"))
+	Client.Must(Client.Command("", "/groupmsg "+user2.Username+","+user3.Username+","+user4.Username+","+user5.Username+","+user6.Username+","+user7.Username+","+user8.Username+","+user9.Username+" foobar"))
+	Client.Must(Client.Command("", "/groupmsg junk foobar"))
+	Client.Must(Client.Command("", "/groupmsg junk,junk2 foobar"))
+}