From 0131980372eb4199d0c3fb9c66fd0cba6fe36cf7 Mon Sep 17 00:00:00 2001
From: Hocuri <hocuri@gmx.de>
Date: Thu, 23 Jul 2020 11:57:54 +0200
Subject: [PATCH] Fix #1739 LastSubject should not be updated for read receipt
 (#1744)

* Fix #1739 LastSubject should not be updated for read receipt

* .
---
 src/dc_receive_imf.rs | 20 +++++++++--------
 src/mimefactory.rs    | 50 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 60 insertions(+), 10 deletions(-)

diff --git a/src/dc_receive_imf.rs b/src/dc_receive_imf.rs
index d18269e64..17a6c6751 100644
--- a/src/dc_receive_imf.rs
+++ b/src/dc_receive_imf.rs
@@ -867,15 +867,17 @@ async fn add_parts(
         chat.update_param(context).await?;
         Ok(())
     }
-    update_last_subject(context, chat_id, mime_parser)
-        .await
-        .unwrap_or_else(|e| {
-            warn!(
-                context,
-                "Could not update LastSubject of chat: {}",
-                e.to_string()
-            )
-        });
+    if !is_mdn {
+        update_last_subject(context, chat_id, mime_parser)
+            .await
+            .unwrap_or_else(|e| {
+                warn!(
+                    context,
+                    "Could not update LastSubject of chat: {}",
+                    e.to_string()
+                )
+            });
+    }
 
     Ok(())
 }
diff --git a/src/mimefactory.rs b/src/mimefactory.rs
index bac979fc4..55ca51ee9 100644
--- a/src/mimefactory.rs
+++ b/src/mimefactory.rs
@@ -1417,6 +1417,54 @@ mod tests {
                 .as_bytes(),
         )
         .await;
+
+        // 5. Receive an mdn (read receipt) and make sure the mdn's subject is not used
+        let t = TestContext::new_alice().await;
+        dc_receive_imf(
+            &t.ctx,
+            b"From: alice@example.com\n\
+            To: Charlie <charlie@example.com>\n\
+            Subject: Hello, Charlie\n\
+            Chat-Version: 1.0\n\
+            Message-ID: <2893@example.com>\n\
+            Date: Sun, 22 Mar 2020 22:37:56 +0000\n\
+            \n\
+            hello\n",
+            "INBOX",
+            1,
+            false,
+        )
+        .await
+        .unwrap();
+        let new_msg = incoming_msg_to_reply_msg(b"From: charlie@example.com\n\
+                 To: alice@example.com\n\
+                 Subject: message opened\n\
+                 Date: Sun, 22 Mar 2020 23:37:57 +0000\n\
+                 Chat-Version: 1.0\n\
+                 Message-ID: <Mr.12345678902@example.com>\n\
+                 Content-Type: multipart/report; report-type=disposition-notification; boundary=\"SNIPP\"\n\
+                 \n\
+                 \n\
+                 --SNIPP\n\
+                 Content-Type: text/plain; charset=utf-8\n\
+                 \n\
+                 Read receipts do not guarantee sth. was read.\n\
+                 \n\
+                 \n\
+                 --SNIPP\n\
+                 Content-Type: message/disposition-notification\n\
+                 \n\
+                 Reporting-UA: Delta Chat 1.28.0\n\
+                 Original-Recipient: rfc822;charlie@example.com\n\
+                 Final-Recipient: rfc822;charlie@example.com\n\
+                 Original-Message-ID: <2893@example.com>\n\
+                 Disposition: manual-action/MDN-sent-automatically; displayed\n\
+                 \n", &t.ctx).await;
+        let mf = MimeFactory::from_msg(&t.ctx, &new_msg, false)
+            .await
+            .unwrap();
+        // The subject string should not be "Re: message opened"
+        assert_eq!("Re: Hello, Charlie", mf.subject_str().await);
     }
 
     async fn first_subject_str(t: TestContext) -> String {
@@ -1453,7 +1501,7 @@ mod tests {
         mf.subject_str().await
     }
 
-    // Creates a mimefactory for a message that replies "Hi" to the incoming message in `imf_raw`.
+    // Creates a `Message` that replies "Hi" to the incoming email in `imf_raw`.
     async fn incoming_msg_to_reply_msg(imf_raw: &[u8], context: &Context) -> Message {
         context
             .set_config(Config::ShowEmails, Some("2"))