From 3048f5d4352f5e4db7b7a6619d1e2afb82f8b8fc Mon Sep 17 00:00:00 2001
From: Ashish Bhate <ashish.bhate@mattermost.com>
Date: Wed, 25 Aug 2021 19:25:30 +0530
Subject: [PATCH] MM-37787: ThreadAutoFollow must be true to enable
 CollapsedThreads (#18253)

* MM-37787: ThreadAutoFollow must be true to enable CollapsedThreads

* check if defaults are valid
---
 i18n/en.json         |  4 ++++
 model/config.go      |  4 ++++
 model/config_test.go | 26 ++++++++++++++++++++++++++
 3 files changed, 34 insertions(+)

diff --git a/i18n/en.json b/i18n/en.json
index fcfb189793..8c3fe054ca 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -7890,6 +7890,10 @@
     "id": "model.config.is_valid.collapsed_threads.app_error",
     "translation": "CollapsedThreads setting must be either disabled,default_on or default_off"
   },
+  {
+    "id": "model.config.is_valid.collapsed_threads.autofollow.app_error",
+    "translation": "ThreadAutoFollow must be true to enable CollapsedThreads"
+  },
   {
     "id": "model.config.is_valid.data_retention.deletion_job_start_time.app_error",
     "translation": "Data retention job start time must be a 24-hour time stamp in the form HH:MM."
diff --git a/model/config.go b/model/config.go
index 1e878f4cb0..2ec109f2c9 100644
--- a/model/config.go
+++ b/model/config.go
@@ -3703,6 +3703,10 @@ func (s *ServiceSettings) isValid() *AppError {
 		return NewAppError("Config.IsValid", "model.config.is_valid.group_unread_channels.app_error", nil, "", http.StatusBadRequest)
 	}
 
+	if *s.CollapsedThreads != CollapsedThreadsDisabled && !*s.ThreadAutoFollow {
+		return NewAppError("Config.IsValid", "model.config.is_valid.collapsed_threads.autofollow.app_error", nil, "", http.StatusBadRequest)
+	}
+
 	if *s.CollapsedThreads != CollapsedThreadsDisabled &&
 		*s.CollapsedThreads != CollapsedThreadsDefaultOn &&
 		*s.CollapsedThreads != CollapsedThreadsDefaultOff {
diff --git a/model/config_test.go b/model/config_test.go
index be1483d0de..7dbd0db33c 100644
--- a/model/config_test.go
+++ b/model/config_test.go
@@ -1467,3 +1467,29 @@ func TestConfigExportSettingsIsValid(t *testing.T) {
 	require.NotNil(t, err)
 	require.Equal(t, "model.config.is_valid.export.retention_days_too_low.app_error", err.Id)
 }
+
+func TestConfigServiceSettingsIsValid(t *testing.T) {
+	cfg := Config{}
+	cfg.SetDefaults()
+
+	err := cfg.ServiceSettings.isValid()
+	require.Nil(t, err)
+
+	*cfg.ServiceSettings.CollapsedThreads = CollapsedThreadsDisabled
+	err = cfg.ServiceSettings.isValid()
+	require.Nil(t, err)
+
+	*cfg.ServiceSettings.ThreadAutoFollow = false
+	err = cfg.ServiceSettings.isValid()
+	require.Nil(t, err)
+
+	*cfg.ServiceSettings.CollapsedThreads = CollapsedThreadsDefaultOff
+	err = cfg.ServiceSettings.isValid()
+	require.NotNil(t, err)
+	require.Equal(t, "model.config.is_valid.collapsed_threads.autofollow.app_error", err.Id)
+
+	*cfg.ServiceSettings.CollapsedThreads = CollapsedThreadsDefaultOn
+	err = cfg.ServiceSettings.isValid()
+	require.NotNil(t, err)
+	require.Equal(t, "model.config.is_valid.collapsed_threads.autofollow.app_error", err.Id)
+}