MM-52532: Fix golangci warnings (#23709)

https://mattermost.atlassian.net/browse/MM-52532

- Replace golint with revive
- Add makezero linter
- Fix all the required linter failures

Some issues in enterprise and public modules
are yet to be fixed. We send this to expediate things.

server/channels/app/command.go

@@ -811,10 +811,10 @@ func possibleAtMentions(message string) []string {
 // is a special character for usernames (dot, dash or underscore). If not, it
 // returns the same string.
 func trimUsernameSpecialChar(word string) (string, bool) {
-	len := len(word)
+	l := len(word)
 
-	if len > 0 && strings.LastIndexAny(word, usernameSpecialChars) == (len-1) {
-		return word[:len-1], true
+	if l > 0 && strings.LastIndexAny(word, usernameSpecialChars) == (l-1) {
+		return word[:l-1], true
 	}
 
 	return word, false

server/channels/app/email/email.go

@@ -894,7 +894,7 @@ func (es *Service) InvalidateVerifyEmailTokensForUser(userID string) *model.AppE
 		return model.NewAppError("InvalidateVerifyEmailTokensForUser", "api.user.invalidate_verify_email_tokens.error", nil, "", http.StatusInternalServerError).Wrap(err)
 	}
 
-	var appErr *model.AppError = nil
+	var appErr *model.AppError
 	for _, token := range tokens {
 		tokenExtra := struct {
 			UserId string

server/channels/app/file.go

@@ -315,7 +315,7 @@ func (a *App) findTeamIdForFilename(post *model.Post, id, filename string) strin
 }
 
 var fileMigrationLock sync.Mutex
-var oldFilenameMatchExp *regexp.Regexp = regexp.MustCompile(`^\/([a-z\d]{26})\/([a-z\d]{26})\/([a-z\d]{26})\/([^\/]+)$`)
+var oldFilenameMatchExp = regexp.MustCompile(`^\/([a-z\d]{26})\/([a-z\d]{26})\/([a-z\d]{26})\/([^\/]+)$`)
 
 // Parse the path from the Filename of the form /{channelID}/{userID}/{uid}/{nameWithExtension}
 func parseOldFilenames(filenames []string, channelID, userID string) [][]string {

server/channels/app/file_helper.go

@@ -25,7 +25,7 @@ func (a *App) removeInaccessibleContentFromFilesSlice(files []*model.FileInfo) (
 		return 0, nil
 	}
 
-	var firstInaccessibleFileTime int64 = 0
+	var firstInaccessibleFileTime int64
 	for _, file := range files {
 		if createAt := file.CreateAt; createAt < lastAccessibleFileTime {
 			file.MakeContentInaccessible()
@@ -143,7 +143,7 @@ func (a *App) getFilteredAccessibleFiles(files []*model.FileInfo, options filter
 			return files, 0, nil
 		}
 		if bounds.noAccessible() {
-			var firstInaccessibleFileTime int64 = 0
+			var firstInaccessibleFileTime int64
 			if lenFiles > 0 {
 				firstFileCreatedAt := files[0].CreateAt
 				lastFileCreatedAt := files[len(files)-1].CreateAt
@@ -194,7 +194,7 @@ func linearFilterFileList(fileList *model.FileInfoList, earliestAccessibleTime i
 // this is the slower fallback that is still safe
 // if we can not assume files are ordered by CreatedAt
 func linearFilterFilesSlice(files []*model.FileInfo, earliestAccessibleTime int64) ([]*model.FileInfo, int64) {
-	var firstInaccessibleFileTime int64 = 0
+	var firstInaccessibleFileTime int64
 	n := 0
 	for i := range files {
 		if createAt := files[i].CreateAt; createAt >= earliestAccessibleTime {

server/channels/app/permissions.go

@@ -282,7 +282,7 @@ func updateRole(a *App, sc *model.SchemeConveyor, roleCreatedName, defaultRoleNa
 
 	_, err = a.UpdateRole(roleCreated)
 	if err != nil {
-		return errors.New(fmt.Sprintf("%v: %v\n", err.Message, err.DetailedError))
+		return fmt.Errorf("failed to update role: %w", err)
 	}
 
 	return nil

server/channels/app/platform/log.go

@@ -141,7 +141,7 @@ func (ps *PlatformService) GetLogsSkipSend(page, perPage int, logFilter *model.L
 		var lineCount int
 		const searchPos = -1
 		b := make([]byte, 1)
-		var endOffset int64 = 0
+		var endOffset int64
 
 		// if the file exists and it's last byte is '\n' - skip it
 		var stat os.FileInfo

server/channels/app/platform/web_hub.go

@@ -442,7 +442,7 @@ func (h *Hub) Start() {
 					})
 					continue
 				}
-				var latestActivity int64 = 0
+				var latestActivity int64
 				for _, conn := range conns {
 					if !conn.active {
 						continue

server/channels/app/plugin_public_keys.go

@@ -3,7 +3,7 @@
 
 package app
 
-var mattermostPluginPublicKey []byte = []byte(`-----BEGIN PGP PUBLIC KEY BLOCK-----
+var mattermostPluginPublicKey = []byte(`-----BEGIN PGP PUBLIC KEY BLOCK-----
 
 mQINBF3YTiEBEACgkhnZ5+xylKZhLVj193b6d/rSQuCU/zwWeZJnqyR8wRsPotXO
 CMXOUM9bTTaGfItCP9KlPPcyrshNEIgqcqhB6TSKkWSyrV5XS95Opd9Esbjw1VZq

server/channels/app/post_helpers.go

@@ -124,7 +124,7 @@ func linearFilterPostList(postList *model.PostList, earliestAccessibleTime int64
 // this is the slower fallback that is still safe if we can not
 // assume posts are ordered by CreatedAt
 func linearFilterPostsSlice(posts []*model.Post, earliestAccessibleTime int64) ([]*model.Post, int64) {
-	var firstInaccessiblePostTime int64 = 0
+	var firstInaccessiblePostTime int64
 	n := 0
 	for i := range posts {
 		if createAt := posts[i].CreateAt; createAt >= earliestAccessibleTime {
@@ -243,7 +243,7 @@ func (a *App) getFilteredAccessiblePosts(posts []*model.Post, options filterPost
 			return posts, 0, nil
 		}
 		if bounds.noAccessible() {
-			var firstInaccessiblePostTime int64 = 0
+			var firstInaccessiblePostTime int64
 			if lenPosts > 0 {
 				firstPostCreatedAt := posts[0].CreateAt
 				lastPostCreatedAt := posts[len(posts)-1].CreateAt

server/channels/app/team.go

@@ -234,7 +234,7 @@ func (a *App) createOnboardingLinkedBoard(c request.CTX, teamId string) (*fb_mod
 		return nil, appErr
 	}
 
-	var template *fb_model.Board = nil
+	var template *fb_model.Board
 	for _, t := range templates {
 		v := t.Properties["trackingTemplateId"]
 		if v == welcomeToBoardsTemplateId {

server/channels/app/team_test.go

@@ -727,7 +727,7 @@ func TestSanitizeTeam(t *testing.T) {
 	}
 
 	copyTeam := func() *model.Team {
-		copy := &model.Team{}
+		copy := &model.Team{} //nolint:revive
 		*copy = *team
 		return copy
 	}

server/channels/app/user.go

@@ -1513,7 +1513,7 @@ func (a *App) InvalidatePasswordRecoveryTokensForUser(userID string) *model.AppE
 		return model.NewAppError("InvalidatePasswordRecoveryTokensForUser", "api.user.invalidate_password_recovery_tokens.error", nil, "", http.StatusInternalServerError).Wrap(err)
 	}
 
-	var appErr *model.AppError = nil
+	var appErr *model.AppError
 	for _, token := range tokens {
 		tokenExtra := struct {
 			UserId string

server/channels/app/user_test.go

@@ -111,24 +111,24 @@ func TestAdjustProfileImage(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
-	_, err := th.App.AdjustImage(bytes.NewReader([]byte{}))
-	require.NotNil(t, err)
+	_, appErr := th.App.AdjustImage(bytes.NewReader([]byte{}))
+	require.NotNil(t, appErr)
 
 	// test image isn't the correct dimensions
 	// it should be adjusted
-	testjpg, error := testutils.ReadTestFile("testjpg.jpg")
-	require.NoError(t, error)
-	adjusted, err := th.App.AdjustImage(bytes.NewReader(testjpg))
-	require.Nil(t, err)
+	testjpg, err := testutils.ReadTestFile("testjpg.jpg")
+	require.NoError(t, err)
+	adjusted, appErr := th.App.AdjustImage(bytes.NewReader(testjpg))
+	require.Nil(t, appErr)
 	assert.True(t, adjusted.Len() > 0)
 	assert.NotEqual(t, testjpg, adjusted)
 
 	// default image should not require adjustment
 	user := th.BasicUser
-	image, err := th.App.GetDefaultProfileImage(user)
-	require.Nil(t, err)
-	image2, err := th.App.AdjustImage(bytes.NewReader(image))
-	require.Nil(t, err)
+	image, appErr := th.App.GetDefaultProfileImage(user)
+	require.Nil(t, appErr)
+	image2, appErr := th.App.AdjustImage(bytes.NewReader(image))
+	require.Nil(t, appErr)
 	assert.Equal(t, image, image2.Bytes())
 }