Create configured folders if they are deleted

python/tests/test_account.py

@@ -2712,6 +2712,22 @@ class TestOnlineAccount:
         # We can't decrypt the message in this chat, so the chat is empty:
         assert len(private_messages) == 0
 
+    def test_delete_deltachat_folder(self, acfactory):
+        """Test that DeltaChat folder is recreated if user deletes it manually."""
+        ac1 = acfactory.get_online_configuring_account(mvbox=True)
+        ac2 = acfactory.get_online_configuring_account()
+        acfactory.wait_configure(ac1)
+
+        ac1.direct_imap.conn.delete_folder("DeltaChat")
+        assert len(ac1.direct_imap.conn.list_folders(pattern="DeltaChat")) == 0
+        acfactory.wait_configure_and_start_io()
+
+        ac2.create_chat(ac1).send_text("hello")
+        msg = ac1._evtracker.wait_next_incoming_message()
+        assert msg.text == "hello"
+
+        assert len(ac1.direct_imap.conn.list_folders(pattern="DeltaChat")) == 1
+
 
 class TestGroupStressTests:
     def test_group_many_members_add_leave_remove(self, acfactory, lp):

src/imap.rs

@@ -552,7 +552,7 @@ impl Imap {
         context: &Context,
         folder: &str,
     ) -> Result<bool> {
-        let newly_selected = self.select_folder(context, Some(folder)).await?;
+        let newly_selected = self.select_or_create_folder(context, folder).await?;
 
         let mailbox = &mut self.config.selected_mailbox.as_ref();
         let mailbox =
@@ -657,9 +657,7 @@ impl Imap {
             .unwrap_or_default();
         let download_limit = context.download_limit().await?;
 
-        let new_emails = self
-            .select_with_uidvalidity(context, folder)
-            .await?;
+        let new_emails = self.select_with_uidvalidity(context, folder).await?;
 
         if !new_emails && !fetch_existing_msgs {
             info!(context, "No new emails in folder {}", folder);

src/imap/select_folder.rs

@@ -15,6 +15,9 @@ pub enum Error {
     #[error("IMAP Folder name invalid: {0}")]
     BadFolderName(String),
 
+    #[error("IMAP folder does not exist: {0}")]
+    NoFolder(String),
+
     #[error("IMAP close/expunge failed")]
     CloseExpungeFailed(#[from] async_imap::error::Error),
 
@@ -110,6 +113,9 @@ impl Imap {
                     Err(async_imap::error::Error::Validate(_)) => {
                         Err(Error::BadFolderName(folder.to_string()))
                     }
+                    Err(async_imap::error::Error::No(_)) => {
+                        Err(Error::NoFolder(folder.to_string()))
+                    }
                     Err(err) => {
                         self.config.selected_folder = None;
                         self.trigger_reconnect(context).await;
@@ -123,6 +129,28 @@ impl Imap {
             Ok(NewlySelected::No)
         }
     }
+
+    /// Selects a folder. Tries to create it once and select again if the folder does not exist.
+    pub(super) async fn select_or_create_folder(
+        &mut self,
+        context: &Context,
+        folder: &str,
+    ) -> Result<NewlySelected> {
+        match self.select_folder(context, Some(folder)).await {
+            Ok(newly_selected) => Ok(newly_selected),
+            Err(err) => match err {
+                Error::NoFolder(_) => {
+                    if let Some(ref mut session) = self.session {
+                        session.create(folder).await?;
+                    } else {
+                        return Err(Error::NoSession);
+                    }
+                    self.select_folder(context, Some(folder)).await
+                }
+                _ => Err(err),
+            },
+        }
+    }
 }
 #[derive(PartialEq, Debug, Copy, Clone, Eq)]
 pub(super) enum NewlySelected {