Remove unneeded Err field in the store result struct (#16322)

* Remove unneeded Err field in the store result struct

* Fixing references to old errors in the tests

app/notification.go

@@ -16,6 +16,7 @@ import (
 	"github.com/mattermost/mattermost-server/v5/store"
 	"github.com/mattermost/mattermost-server/v5/utils"
 	"github.com/mattermost/mattermost-server/v5/utils/markdown"
+	"github.com/pkg/errors"
 )
 
 func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *model.Channel, sender *model.User, parentPostList *model.PostList, setOnline bool) ([]string, error) {
@@ -43,7 +44,7 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 		gchan = make(chan store.StoreResult, 1)
 		go func() {
 			groupsMap, err := a.getGroupsAllowedForReferenceInChannel(channel, team)
-			gchan <- store.StoreResult{Data: groupsMap, Err: err}
+			gchan <- store.StoreResult{Data: groupsMap, NErr: err}
 			close(gchan)
 		}()
 	}
@@ -73,8 +74,8 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	groups := make(map[string]*model.Group)
 	if gchan != nil {
 		result = <-gchan
-		if result.Err != nil {
-			return nil, result.Err
+		if result.NErr != nil {
+			return nil, result.NErr
 		}
 		groups = result.Data.(map[string]*model.Group)
 	}
@@ -818,7 +819,7 @@ func (a *App) allowGroupMentions(post *model.Post) bool {
 }
 
 // getGroupsAllowedForReferenceInChannel returns a map of groups allowed for reference in a given channel and team.
-func (a *App) getGroupsAllowedForReferenceInChannel(channel *model.Channel, team *model.Team) (map[string]*model.Group, *model.AppError) {
+func (a *App) getGroupsAllowedForReferenceInChannel(channel *model.Channel, team *model.Team) (map[string]*model.Group, error) {
 	var err error
 	groupsMap := make(map[string]*model.Group)
 	opts := model.GroupSearchOpts{FilterAllowReference: true}
@@ -831,7 +832,7 @@ func (a *App) getGroupsAllowedForReferenceInChannel(channel *model.Channel, team
 			groups, err = a.Srv().Store.Group().GetGroupsByTeam(team.Id, opts)
 		}
 		if err != nil {
-			return nil, model.NewAppError("getGroupsAllowedForReferenceInChannel", "app.select_error", nil, err.Error(), http.StatusInternalServerError)
+			return nil, errors.Wrap(err, "unable to get groups")
 		}
 		for _, group := range groups {
 			if group.Group.Name != nil {
@@ -843,7 +844,7 @@ func (a *App) getGroupsAllowedForReferenceInChannel(channel *model.Channel, team
 
 	groups, err := a.Srv().Store.Group().GetGroups(0, 0, opts)
 	if err != nil {
-		return nil, model.NewAppError("getGroupsAllowedForReferenceInChannel", "app.select_error", nil, err.Error(), http.StatusInternalServerError)
+		return nil, errors.Wrap(err, "unable to get groups")
 	}
 	for _, group := range groups {
 		if group.Name != nil {

app/notification_test.go

@@ -2465,15 +2465,14 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 	defer th.TearDown()
 
 	var err *model.AppError
-	var groupsMap map[string]*model.Group
 
 	team := th.BasicTeam
 	channel := th.BasicChannel
 	group1 := th.CreateGroup()
 
 	t.Run("should return empty map when no groups with allow reference", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(channel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(channel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 0)
 	})
 
@@ -2483,8 +2482,8 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 
 	group2 := th.CreateGroup()
 	t.Run("should only return groups with allow reference", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(channel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(channel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 1)
 		require.Nil(t, groupsMap[*group2.Name])
 		require.Equal(t, groupsMap[*group1.Name], group1)
@@ -2507,8 +2506,8 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 	require.Nil(t, err)
 
 	t.Run("should return only groups synced to channel if channel is group constrained", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(constrainedChannel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(constrainedChannel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 1)
 		require.Nil(t, groupsMap[*group2.Name])
 		require.Equal(t, groupsMap[*group1.Name], group1)
@@ -2532,8 +2531,8 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 	require.Nil(t, err)
 
 	t.Run("should return union of groups synced to team and any channels if team is group constrained", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(channel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(channel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 2)
 		require.Nil(t, groupsMap[*group3.Name])
 		require.Equal(t, groupsMap[*group2.Name], group2)
@@ -2541,8 +2540,8 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 	})
 
 	t.Run("should return only subset of groups synced to channel for group constrained channel when team is also group constrained", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(constrainedChannel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(constrainedChannel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 1)
 		require.Nil(t, groupsMap[*group3.Name])
 		require.Nil(t, groupsMap[*group2.Name])
@@ -2554,8 +2553,8 @@ func TestGetGroupsAllowedForReferenceInChannel(t *testing.T) {
 	require.Nil(t, err)
 
 	t.Run("should return all groups when team and channel are not group constrained", func(t *testing.T) {
-		groupsMap, err = th.App.getGroupsAllowedForReferenceInChannel(channel, team)
-		require.Nil(t, err)
+		groupsMap, nErr := th.App.getGroupsAllowedForReferenceInChannel(channel, team)
+		require.Nil(t, nErr)
 		require.Len(t, groupsMap, 3)
 		require.Equal(t, groupsMap[*group1.Name], group1)
 		require.Equal(t, groupsMap[*group2.Name], group2)

store/store.go

@@ -14,7 +14,6 @@ import (
 
 type StoreResult struct {
 	Data interface{}
-	Err  *model.AppError
 
 	// NErr a temporary field used by the new code for the AppError migration. This will later become Err when the entire store is migrated.
 	NErr error