Replace mpsc::{Sender,Receiver} by VecDeque (#260)

Author: soywod

Cargo.toml

@@ -29,7 +29,7 @@ bufstream = "0.1.3"
 imap-proto = "0.16.1"
 nom = { version = "7.1.0", default-features = false }
 base64 = "0.22"
-chrono = { version = "0.4", default-features = false, features = ["std"]}
+chrono = { version = "0.4.37", default-features = false, features = ["std"]}
 lazy_static = "1.4"
 ouroboros = "0.18.0"
 

src/client.rs

@@ -3,10 +3,10 @@ use bufstream::BufStream;
 use chrono::{DateTime, FixedOffset};
 use imap_proto::Response;
 use std::collections::HashSet;
+use std::collections::VecDeque;
 use std::io::{Read, Write};
 use std::ops::{Deref, DerefMut};
 use std::str;
-use std::sync::mpsc;
 
 use super::authenticator::Authenticator;
 use super::error::{Bad, Bye, Error, No, ParseError, Result, TagMismatch, ValidateError};
@@ -141,11 +141,9 @@ fn validate_sequence_set(
 #[derive(Debug)]
 pub struct Session<T: Read + Write> {
     conn: Connection<T>,
-    pub(crate) unsolicited_responses_tx: mpsc::Sender<UnsolicitedResponse>,
-
     /// Server responses that are not related to the current command. See also the note on
     /// [unilateral server responses in RFC 3501](https://tools.ietf.org/html/rfc3501#section-7).
-    pub unsolicited_responses: mpsc::Receiver<UnsolicitedResponse>,
+    pub(crate) unsolicited_responses: VecDeque<UnsolicitedResponse>,
 }
 
 /// An (unauthenticated) handle to talk to an IMAP server. This is what you get when first
@@ -262,7 +260,7 @@ impl<'a, T: Read + Write> AppendCmd<'a, T> {
         self.session.stream.flush()?;
         self.session
             .read_response()
-            .and_then(|(lines, _)| parse_append(&lines, &mut self.session.unsolicited_responses_tx))
+            .and_then(|(lines, _)| parse_append(&lines, &mut self.session.unsolicited_responses))
     }
 }
 
@@ -370,10 +368,10 @@ impl<T: Read + Write> Client<T> {
     ///
     /// This allows reading capabilities before authentication.
     pub fn capabilities(&mut self) -> Result<Capabilities> {
-        // Create a temporary channel as we do not care about out of band responses before login
-        let (mut tx, _rx) = mpsc::channel();
+        // Create a temporary vec deque as we do not care about out of band responses before login
+        let mut unsolicited_responses = VecDeque::new();
         self.run_command_and_read_response("CAPABILITY")
-            .and_then(|lines| Capabilities::parse(lines, &mut tx))
+            .and_then(|lines| Capabilities::parse(lines, &mut unsolicited_responses))
     }
 
     /// Log in to the IMAP server. Upon success a [`Session`](struct.Session.html) instance is
@@ -530,14 +528,17 @@ impl<T: Read + Write> Client<T> {
 impl<T: Read + Write> Session<T> {
     // not public, just to avoid duplicating the channel creation code
     fn new(conn: Connection<T>) -> Self {
-        let (tx, rx) = mpsc::channel();
         Session {
             conn,
-            unsolicited_responses: rx,
-            unsolicited_responses_tx: tx,
+            unsolicited_responses: VecDeque::new(),
         }
     }
 
+    /// Takes all the unsolicited responses received thus far.
+    pub fn take_all_unsolicited(&mut self) -> impl ExactSizeIterator<Item = UnsolicitedResponse> {
+        std::mem::take(&mut self.unsolicited_responses).into_iter()
+    }
+
     /// Selects a mailbox
     ///
     /// The `SELECT` command selects a mailbox so that messages in the mailbox can be accessed.
@@ -561,7 +562,7 @@ impl<T: Read + Write> Session<T> {
             "SELECT {}",
             validate_str("SELECT", "mailbox", mailbox_name.as_ref())?
         ))
-        .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses_tx))
+        .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses))
     }
 
     /// The `EXAMINE` command is identical to [`Session::select`] and returns the same output;
@@ -573,7 +574,7 @@ impl<T: Read + Write> Session<T> {
             "EXAMINE {}",
             validate_str("EXAMINE", "mailbox", mailbox_name.as_ref())?
         ))
-        .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses_tx))
+        .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses))
     }
 
     /// Fetch retrieves data associated with a set of messages in the mailbox.
@@ -640,15 +641,15 @@ impl<T: Read + Write> Session<T> {
         query: impl AsRef<str>,
     ) -> Result<Fetches> {
         if sequence_set.as_ref().is_empty() {
-            Fetches::parse(vec![], &mut self.unsolicited_responses_tx)
+            Fetches::parse(vec![], &mut self.unsolicited_responses)
         } else {
             let synopsis = "FETCH";
             self.run_command_and_read_response(&format!(
                 "FETCH {} {}",
                 validate_sequence_set(synopsis, "seq", sequence_set.as_ref())?,
                 validate_str_noquote(synopsis, "query", query.as_ref())?
             ))
-            .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses))
         }
     }
 
@@ -660,22 +661,22 @@ impl<T: Read + Write> Session<T> {
         query: impl AsRef<str>,
     ) -> Result<Fetches> {
         if uid_set.as_ref().is_empty() {
-            Fetches::parse(vec![], &mut self.unsolicited_responses_tx)
+            Fetches::parse(vec![], &mut self.unsolicited_responses)
         } else {
             let synopsis = "UID FETCH";
             self.run_command_and_read_response(&format!(
                 "UID FETCH {} {}",
                 validate_sequence_set(synopsis, "seq", uid_set.as_ref())?,
                 validate_str_noquote(synopsis, "query", query.as_ref())?
             ))
-            .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses))
         }
     }
 
     /// Noop always succeeds, and it does nothing.
     pub fn noop(&mut self) -> Result<()> {
         self.run_command_and_read_response("NOOP")
-            .and_then(|lines| parse_noop(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| parse_noop(lines, &mut self.unsolicited_responses))
     }
 
     /// Logout informs the server that the client is done with the connection.
@@ -807,7 +808,7 @@ impl<T: Read + Write> Session<T> {
     /// one of the listed capabilities. See [`Capabilities`] for further details.
     pub fn capabilities(&mut self) -> Result<Capabilities> {
         self.run_command_and_read_response("CAPABILITY")
-            .and_then(|lines| Capabilities::parse(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| Capabilities::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`EXPUNGE` command](https://tools.ietf.org/html/rfc3501#section-6.4.3) permanently
@@ -816,7 +817,7 @@ impl<T: Read + Write> Session<T> {
     pub fn expunge(&mut self) -> Result<Deleted> {
         self.run_command("EXPUNGE")?;
         self.read_response()
-            .and_then(|(lines, _)| parse_expunge(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|(lines, _)| parse_expunge(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`UID EXPUNGE` command](https://tools.ietf.org/html/rfc4315#section-2.1) permanently
@@ -844,7 +845,7 @@ impl<T: Read + Write> Session<T> {
     pub fn uid_expunge(&mut self, uid_set: impl AsRef<str>) -> Result<Deleted> {
         self.run_command(&format!("UID EXPUNGE {}", uid_set.as_ref()))?;
         self.read_response()
-            .and_then(|(lines, _)| parse_expunge(lines, &mut self.unsolicited_responses_tx))
+            .and_then(|(lines, _)| parse_expunge(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`CHECK` command](https://tools.ietf.org/html/rfc3501#section-6.4.1) requests a
@@ -934,7 +935,7 @@ impl<T: Read + Write> Session<T> {
             sequence_set.as_ref(),
             query.as_ref()
         ))
-        .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// Equivalent to [`Session::store`], except that all identifiers in `sequence_set` are
@@ -949,7 +950,7 @@ impl<T: Read + Write> Session<T> {
             uid_set.as_ref(),
             query.as_ref()
         ))
-        .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`COPY` command](https://tools.ietf.org/html/rfc3501#section-6.4.7) copies the
@@ -1084,7 +1085,7 @@ impl<T: Read + Write> Session<T> {
             quote!(reference_name.unwrap_or("")),
             mailbox_pattern.unwrap_or("\"\"")
         ))
-        .and_then(|lines| Names::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| Names::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`LSUB` command](https://tools.ietf.org/html/rfc3501#section-6.3.9) returns a subset of
@@ -1112,7 +1113,7 @@ impl<T: Read + Write> Session<T> {
             quote!(reference_name.unwrap_or("")),
             mailbox_pattern.unwrap_or("")
         ))
-        .and_then(|lines| Names::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| Names::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`STATUS` command](https://tools.ietf.org/html/rfc3501#section-6.3.10) requests the
@@ -1161,9 +1162,7 @@ impl<T: Read + Write> Session<T> {
             validate_str("STATUS", "mailbox", mailbox_name)?,
             data_items.as_ref()
         ))
-        .and_then(|lines| {
-            parse_status(&lines[..], mailbox_name, &mut self.unsolicited_responses_tx)
-        })
+        .and_then(|lines| parse_status(&lines[..], mailbox_name, &mut self.unsolicited_responses))
     }
 
     /// This method returns a handle that lets you use the [`IDLE`
@@ -1264,15 +1263,15 @@ impl<T: Read + Write> Session<T> {
     ///  - `SINCE <date>`: Messages whose internal date (disregarding time and timezone) is within or later than the specified date.
     pub fn search(&mut self, query: impl AsRef<str>) -> Result<HashSet<Seq>> {
         self.run_command_and_read_response(&format!("SEARCH {}", query.as_ref()))
-            .and_then(|lines| parse_id_set(&lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| parse_id_set(&lines, &mut self.unsolicited_responses))
     }
 
     /// Equivalent to [`Session::search`], except that the returned identifiers
     /// are [`Uid`] instead of [`Seq`]. See also the [`UID`
     /// command](https://tools.ietf.org/html/rfc3501#section-6.4.8).
     pub fn uid_search(&mut self, query: impl AsRef<str>) -> Result<HashSet<Uid>> {
         self.run_command_and_read_response(&format!("UID SEARCH {}", query.as_ref()))
-            .and_then(|lines| parse_id_set(&lines, &mut self.unsolicited_responses_tx))
+            .and_then(|lines| parse_id_set(&lines, &mut self.unsolicited_responses))
     }
 
     /// This issues the [SORT command](https://tools.ietf.org/html/rfc5256#section-3),
@@ -1292,7 +1291,7 @@ impl<T: Read + Write> Session<T> {
             charset,
             query.as_ref()
         ))
-        .and_then(|lines| parse_id_seq(&lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| parse_id_seq(&lines, &mut self.unsolicited_responses))
     }
 
     /// Equivalent to [`Session::sort`], except that it returns [`Uid`]s.
@@ -1310,7 +1309,7 @@ impl<T: Read + Write> Session<T> {
             charset,
             query.as_ref()
         ))
-        .and_then(|lines| parse_id_seq(&lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| parse_id_seq(&lines, &mut self.unsolicited_responses))
     }
 
     /// The [`SETACL` command](https://datatracker.ietf.org/doc/html/rfc4314#section-3.1)
@@ -1373,7 +1372,7 @@ impl<T: Read + Write> Session<T> {
             "GETACL {}",
             validate_str("GETACL", "mailbox", mailbox_name.as_ref())?
         ))
-        .and_then(|lines| AclResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| AclResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`LISTRIGHTS` command](https://datatracker.ietf.org/doc/html/rfc4314#section-3.4)
@@ -1394,7 +1393,7 @@ impl<T: Read + Write> Session<T> {
             validate_str("LISTRIGHTS", "mailbox", mailbox_name.as_ref())?,
             validate_str("LISTRIGHTS", "identifier", identifier.as_ref())?
         ))
-        .and_then(|lines| ListRightsResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| ListRightsResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`MYRIGHTS` command](https://datatracker.ietf.org/doc/html/rfc4314#section-3.5)
@@ -1408,7 +1407,7 @@ impl<T: Read + Write> Session<T> {
             "MYRIGHTS {}",
             validate_str("MYRIGHTS", "mailbox", mailbox_name.as_ref())?,
         ))
-        .and_then(|lines| MyRightsResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| MyRightsResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`SETQUOTA` command](https://datatracker.ietf.org/doc/html/rfc2087#section-4.1)
@@ -1428,7 +1427,7 @@ impl<T: Read + Write> Session<T> {
             validate_str("SETQUOTA", "quota_root", quota_root.as_ref())?,
             limits,
         ))
-        .and_then(|lines| QuotaResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| QuotaResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`GETQUOTA` command](https://datatracker.ietf.org/doc/html/rfc2087#section-4.2)
@@ -1439,7 +1438,7 @@ impl<T: Read + Write> Session<T> {
             "GETQUOTA {}",
             validate_str("GETQUOTA", "quota_root", quota_root.as_ref())?
         ))
-        .and_then(|lines| QuotaResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| QuotaResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     /// The [`GETQUOTAROOT` command](https://datatracker.ietf.org/doc/html/rfc2087#section-4.3)
@@ -1450,7 +1449,7 @@ impl<T: Read + Write> Session<T> {
             "GETQUOTAROOT {}",
             validate_str("GETQUOTAROOT", "mailbox", mailbox_name.as_ref())?
         ))
-        .and_then(|lines| QuotaRootResponse::parse(lines, &mut self.unsolicited_responses_tx))
+        .and_then(|lines| QuotaRootResponse::parse(lines, &mut self.unsolicited_responses))
     }
 
     // these are only here because they are public interface, the rest is in `Connection`

src/extensions/list_status.rs

@@ -7,9 +7,9 @@ use crate::parse::try_handle_unilateral;
 use crate::types::{Mailbox, Name, UnsolicitedResponse};
 use imap_proto::types::{MailboxDatum, Response, StatusAttribute};
 use ouroboros::self_referencing;
+use std::collections::VecDeque;
 use std::io::{Read, Write};
 use std::slice::Iter;
-use std::sync::mpsc;
 
 /// A wrapper for one or more [`Name`] responses paired with optional [`Mailbox`] responses.
 ///
@@ -27,7 +27,7 @@ impl ExtendedNames {
     /// Parse one or more LIST-STATUS responses from a response buffer
     pub(crate) fn parse(
         owned: Vec<u8>,
-        unsolicited: &mut mpsc::Sender<UnsolicitedResponse>,
+        unsolicited: &mut VecDeque<UnsolicitedResponse>,
     ) -> core::result::Result<Self, Error> {
         ExtendedNamesTryBuilder {
             data: owned,
@@ -145,13 +145,13 @@ impl<T: Read + Write> Session<T> {
         data_items: &str,
     ) -> Result<ExtendedNames> {
         let reference = validate_str("LIST-STATUS", "reference", reference_name.unwrap_or(""))?;
-        self.run_command_and_read_response(&format!(
+        let lines = self.run_command_and_read_response(format!(
             "LIST {} {} RETURN (STATUS {})",
             &reference,
             mailbox_pattern.unwrap_or("\"\""),
             data_items
-        ))
-        .and_then(|lines| ExtendedNames::parse(lines, &mut self.unsolicited_responses_tx))
+        ))?;
+        ExtendedNames::parse(lines, &mut self.unsolicited_responses)
     }
 }
 
@@ -171,9 +171,9 @@ mod tests {
                     * LIST (\\UnMarked) \".\" feeds\r\n\
                     * LIST () \".\" feeds.test\r\n\
                     * STATUS feeds.test (HIGHESTMODSEQ 757)\r\n";
-        let (mut send, recv) = mpsc::channel();
-        let fetches = ExtendedNames::parse(lines.to_vec(), &mut send).unwrap();
-        assert!(recv.try_recv().is_err());
+        let mut queue = VecDeque::new();
+        let fetches = ExtendedNames::parse(lines.to_vec(), &mut queue).unwrap();
+        assert_eq!(queue.pop_front(), None);
         assert!(!fetches.is_empty());
         assert_eq!(fetches.len(), 4);
         let (name, status) = fetches.get(0).unwrap();

src/extensions/metadata.rs

@@ -15,8 +15,8 @@ use crate::error::{Error, ParseError, Result};
 use crate::parse::try_handle_unilateral;
 use crate::types::*;
 use imap_proto::types::{MailboxDatum, Metadata, Response, ResponseCode};
+use std::collections::VecDeque;
 use std::io::{Read, Write};
-use std::sync::mpsc;
 
 // for intra-doc links
 #[allow(unused_imports)]
@@ -83,7 +83,7 @@ impl MetadataDepth {
 
 fn parse_metadata<'a>(
     mut lines: &'a [u8],
-    unsolicited: &'a mut mpsc::Sender<UnsolicitedResponse>,
+    unsolicited: &'a mut VecDeque<UnsolicitedResponse>,
 ) -> Result<Vec<Metadata>> {
     let mut res: Vec<Metadata> = Vec::new();
     loop {
@@ -197,7 +197,7 @@ impl<T: Read + Write> Session<T> {
             .as_str(),
         );
         let (lines, ok) = self.run(command)?;
-        let meta = parse_metadata(&lines[..ok], &mut self.unsolicited_responses_tx)?;
+        let meta = parse_metadata(&lines[..ok], &mut self.unsolicited_responses)?;
         let missed = if maxsize.is_some() {
             if let Ok((_, Response::Done { code, .. })) =
                 imap_proto::parser::parse_response(&lines[ok..])