test: write a unit test for group chat permissions

crates/core/database/fixtures/group_with_members.json

@@ -0,0 +1,28 @@
+[
+  {
+    "_object_type": "User",
+    "_id": "__ID:0__",
+    "username": "Owner",
+    "discriminator": "0001"
+  },
+  {
+    "_object_type": "User",
+    "_id": "__ID:1__",
+    "username": "Member",
+    "discriminator": "0001"
+  },
+  {
+    "_object_type": "User",
+    "_id": "__ID:2__",
+    "username": "Member",
+    "discriminator": "0002"
+  },
+  {
+    "_object_type": "Channel",
+    "_id": "__ID:3__",
+    "channel_type": "Group",
+    "name": "My Group",
+    "owner": "__ID:0__",
+    "recipients": ["__ID:0__", "__ID:1__", "__ID:2__"]
+  }
+]

crates/core/database/src/models/channels/model.rs

@@ -695,6 +695,32 @@ mod tests {
 
     use crate::{fixture, util::permissions::DatabasePermissionQuery};
 
+    #[async_std::test]
+    async fn permissions_group_channel() {
+        database_test!(|db| async move {
+            fixture!(db, "group_with_members",
+                owner user 0
+                member1 user 1
+                member2 user 2
+                channel channel 3);
+
+            let mut query = DatabasePermissionQuery::new(&db, &owner).channel(&channel);
+            assert!(calculate_channel_permissions(&mut query)
+                .await
+                .has_channel_permission(ChannelPermission::SendMessage));
+
+            let mut query = DatabasePermissionQuery::new(&db, &member1).channel(&channel);
+            assert!(calculate_channel_permissions(&mut query)
+                .await
+                .has_channel_permission(ChannelPermission::SendMessage));
+
+            let mut query = DatabasePermissionQuery::new(&db, &member2).channel(&channel);
+            assert!(!calculate_channel_permissions(&mut query)
+                .await
+                .has_channel_permission(ChannelPermission::SendMessage));
+        });
+    }
+
     #[async_std::test]
     async fn permissions_text_channel() {
         database_test!(|db| async move {