Complete unit tests

src/tui/event.rs

@@ -53,11 +53,11 @@ pub struct EventChannel {
     receiver: mpsc::Receiver<Event>,
 }
 
-#[cfg_attr(test, automock)]
 pub trait IKeyEventSender {
     fn send_key(&self, key_event: KeyEvent) -> Result<(), EventError>;
 }
 
+#[cfg_attr(test, automock)]
 pub trait IFetchCompleteEventSender {
     fn send_fetch_complete(&self) -> Result<(), EventError>;
 }

src/tui/lib/external/musicbrainz/daemon/mod.rs

@@ -21,6 +21,7 @@ struct JobQueue {
     background_queue: VecDeque<JobInstance>,
 }
 
+#[derive(Debug)]
 struct Job {
     priority: JobPriority,
     instance: JobInstance,
@@ -32,21 +33,26 @@ impl Job {
     }
 }
 
+#[derive(Debug)]
 enum JobPriority {
+    #[cfg(test)]
     Foreground,
     Background,
 }
 
+#[derive(Debug)]
 struct JobInstance {
     result_sender: ResultSender,
     requests: VecDeque<MbParams>,
 }
 
+#[derive(Debug, PartialEq, Eq)]
 enum JobInstanceStatus {
     Continue,
     Complete,
 }
 
+#[derive(Debug, PartialEq, Eq)]
 enum JobInstanceError {
     ReturnChannelDisconnected,
     EventChannelDisconnected,
@@ -61,6 +67,7 @@ impl JobInstance {
     }
 }
 
+#[derive(Debug, PartialEq, Eq)]
 enum JobError {
     JobQueueEmpty,
     EventChannelDisconnected,
@@ -130,6 +137,7 @@ impl JobSender {
 }
 
 impl MusicBrainzDaemon {
+    // GRCOV_EXCL_START
     pub fn run<MB: IMusicBrainz + 'static, ES: IFetchCompleteEventSender + 'static>(
         musicbrainz: MB,
         job_receiver: JobReceiver,
@@ -163,6 +171,7 @@ impl MusicBrainzDaemon {
             }
         }
     }
+    // GRCOV_EXCL_STOP
 
     fn enqueue_all_pending_jobs(&mut self) -> Result<(), Error> {
         loop {
@@ -178,7 +187,7 @@ impl MusicBrainzDaemon {
 
     fn execute_next_job(&mut self) -> Result<(), JobError> {
         if let Some(instance) = self.job_queue.front_mut() {
-            let result = instance.execute_next(&mut self.musicbrainz, &mut self.event_sender);
+            let result = instance.execute_next(&mut *self.musicbrainz, &mut *self.event_sender);
             match result {
                 Ok(JobInstanceStatus::Continue) => {}
                 Ok(JobInstanceStatus::Complete)
@@ -209,8 +218,8 @@ impl MusicBrainzDaemon {
 impl JobInstance {
     fn execute_next(
         &mut self,
-        musicbrainz: &mut Box<dyn IMusicBrainz>,
+        musicbrainz: &mut dyn IMusicBrainz,
-        event_sender: &mut Box<dyn IFetchCompleteEventSender>,
+        event_sender: &mut dyn IFetchCompleteEventSender,
     ) -> Result<JobInstanceStatus, JobInstanceError> {
         // self.requests can be empty if the caller submits an empty job.
         if let Some(params) = self.requests.pop_front() {
@@ -226,8 +235,8 @@ impl JobInstance {
 
     fn execute(
         &mut self,
-        musicbrainz: &mut Box<dyn IMusicBrainz>,
+        musicbrainz: &mut dyn IMusicBrainz,
-        event_sender: &mut Box<dyn IFetchCompleteEventSender>,
+        event_sender: &mut dyn IFetchCompleteEventSender,
         api_params: MbParams,
     ) -> Result<(), JobInstanceError> {
         match api_params {
@@ -248,7 +257,7 @@ impl JobInstance {
 
     fn return_result(
         &mut self,
-        event_sender: &mut Box<dyn IFetchCompleteEventSender>,
+        event_sender: &mut dyn IFetchCompleteEventSender,
         result: Result<MatchStateInfo, ApiError>,
     ) -> Result<(), JobInstanceError> {
         self.result_sender
@@ -291,6 +300,7 @@ impl JobQueue {
 
     fn push_back(&mut self, job: Job) {
         match job.priority {
+            #[cfg(test)]
             JobPriority::Foreground => self.foreground_queue.push_back(job.instance),
             JobPriority::Background => self.background_queue.push_back(job.instance),
         }
@@ -299,190 +309,388 @@ impl JobQueue {
 
 #[cfg(test)]
 mod tests {
-    //     fn event_channel() -> (EventSender, EventReceiver) {
+    use mockall::{predicate, Sequence};
-    //         let event_channel = EventChannel::new();
+    use musichoard::collection::{
-    //         let events_tx = event_channel.sender();
+        album::AlbumMeta,
-    //         let events_rx = event_channel.receiver();
+        artist::ArtistMeta,
-    //         (events_tx, events_rx)
+        musicbrainz::{IMusicBrainzRef, Mbid},
-    //     }
+    };
 
+    use crate::tui::{
+        event::{Event, EventError, MockIFetchCompleteEventSender},
+        lib::interface::musicbrainz::api::{Match, MockIMusicBrainz},
+        testmod::COLLECTION,
+    };
 
-    //     fn album_expectations_1() -> (AlbumMeta, Vec<Match<AlbumMeta>>) {
+    use super::*;
-    //         let album_1 = COLLECTION[1].albums[0].meta.clone();
-    //         let album_4 = COLLECTION[1].albums[3].meta.clone();
-
-    //         let album_match_1_1 = Match::new(100, album_1.clone());
-    //         let album_match_1_2 = Match::new(50, album_4.clone());
-    //         let matches_1 = vec![album_match_1_1.clone(), album_match_1_2.clone()];
-
-    //         (album_1, matches_1)
-    //     }
-
-    //     fn album_expectations_4() -> (AlbumMeta, Vec<Match<AlbumMeta>>) {
-    //         let album_1 = COLLECTION[1].albums[0].meta.clone();
-    //         let album_4 = COLLECTION[1].albums[3].meta.clone();
-
-    //         let album_match_4_1 = Match::new(100, album_4.clone());
-    //         let album_match_4_2 = Match::new(30, album_1.clone());
-    //         let matches_4 = vec![album_match_4_1.clone(), album_match_4_2.clone()];
-
-    //         (album_4, matches_4)
-    //     }
-
-    //     fn search_release_group_expectation(
-    //         api: &mut MockIMusicBrainz,
-    //         seq: &mut Sequence,
-    //         arid: &Mbid,
-    //         album: &AlbumMeta,
-    //         matches: &[Match<AlbumMeta>],
-    //     ) {
-    //         let result = Ok(matches.to_owned());
-    //         api.expect_search_release_group()
-    //             .with(predicate::eq(arid.clone()), predicate::eq(album.clone()))
-    //             .times(1)
-    //             .in_sequence(seq)
-    //             .return_once(|_, _| result);
-    //     }
-
-    //     #[test]
-    //     fn fetch_albums() {
-    //         let mut mb_api = MockIMusicBrainz::new();
-
-    //         let arid: Mbid = "11111111-1111-1111-1111-111111111111".try_into().unwrap();
-
-    //         let (album_1, matches_1) = album_expectations_1();
-    //         let (album_4, matches_4) = album_expectations_4();
-
-    //         // Other albums have an MBID and so they will be skipped.
-    //         let mut seq = Sequence::new();
-
-    //         search_release_group_expectation(&mut mb_api, &mut seq, &arid, &album_1, &matches_1);
-    //         search_release_group_expectation(&mut mb_api, &mut seq, &arid, &album_4, &matches_4);
-
-    //         let music_hoard = music_hoard(COLLECTION.to_owned());
-    //         let (events_tx, events_rx) = event_channel();
-    //         let inner = AppInner::new(music_hoard, mb_api, events_tx);
-
-    //         let (fetch_tx, fetch_rx) = mpsc::channel();
-    //         // Use the second artist for this test.
-    //         let handle = AppMachine::spawn_fetch_thread(&inner, &COLLECTION[1], fetch_tx);
-    //         handle.join().unwrap();
-
-    //         assert_eq!(events_rx.try_recv().unwrap(), Event::FetchResultReady);
-    //         let result = fetch_rx.try_recv().unwrap();
-    //         let expected = Ok(MatchStateInfo::Album(AlbumMatches {
-    //             matching: album_1.clone(),
-    //             list: matches_1.iter().cloned().map(Into::into).collect(),
-    //         }));
-    //         assert_eq!(result, expected);
-
-    //         assert_eq!(events_rx.try_recv().unwrap(), Event::FetchResultReady);
-    //         let result = fetch_rx.try_recv().unwrap();
-    //         let expected = Ok(MatchStateInfo::Album(AlbumMatches {
-    //             matching: album_4.clone(),
-    //             list: matches_4.iter().cloned().map(Into::into).collect(),
-    //         }));
-    //         assert_eq!(result, expected);
-    //     }
-
-    //     fn artist_expectations() -> (ArtistMeta, Vec<Match<ArtistMeta>>) {
-    //         let artist = COLLECTION[3].meta.clone();
-
-    //         let artist_match_1 = Match::new(100, artist.clone());
-    //         let artist_match_2 = Match::new(50, artist.clone());
-    //         let matches = vec![artist_match_1.clone(), artist_match_2.clone()];
-
-    //         (artist, matches)
-    //     }
-
-    //     fn search_artist_expectation(
-    //         api: &mut MockIMusicBrainz,
-    //         seq: &mut Sequence,
-    //         artist: &ArtistMeta,
-    //         matches: &[Match<ArtistMeta>],
-    //     ) {
-    //         let result = Ok(matches.to_owned());
-    //         api.expect_search_artist()
-    //             .with(predicate::eq(artist.clone()))
-    //             .times(1)
-    //             .in_sequence(seq)
-    //             .return_once(|_| result);
-    //     }
-
-    //     #[test]
-    //     fn fetch_artist() {
-    //         let mut mb_api = MockIMusicBrainz::new();
-
-    //         let (artist, matches) = artist_expectations();
-    //         let mut seq = Sequence::new();
-    //         search_artist_expectation(&mut mb_api, &mut seq, &artist, &matches);
-
-    //         let music_hoard = music_hoard(COLLECTION.to_owned());
-    //         let (events_tx, events_rx) = event_channel();
-    //         let inner = AppInner::new(music_hoard, mb_api, events_tx);
-
-    //         let (fetch_tx, fetch_rx) = mpsc::channel();
-    //         // Use the fourth artist for this test as they have no MBID.
-    //         let handle = AppMachine::spawn_fetch_thread(&inner, &COLLECTION[3], fetch_tx);
-    //         handle.join().unwrap();
-
-    //         assert_eq!(events_rx.try_recv().unwrap(), Event::FetchResultReady);
-    //         let result = fetch_rx.try_recv().unwrap();
-    //         let expected = Ok(MatchStateInfo::Artist(ArtistMatches {
-    //             matching: artist.clone(),
-    //             list: matches.iter().cloned().map(Into::into).collect(),
-    //         }));
-    //         assert_eq!(result, expected);
-    //     }
-
-    //     #[test]
-    //     fn fetch_artist_fetch_disconnect() {
-    //         let mut mb_api = MockIMusicBrainz::new();
-
-    //         let (artist, matches) = artist_expectations();
-    //         let mut seq = Sequence::new();
-    //         search_artist_expectation(&mut mb_api, &mut seq, &artist, &matches);
-
-    //         let music_hoard = music_hoard(COLLECTION.to_owned());
-    //         let (events_tx, events_rx) = event_channel();
-    //         let inner = AppInner::new(music_hoard, mb_api, events_tx);
-
-    //         let (fetch_tx, _) = mpsc::channel();
-    //         // Use the fourth artist for this test as they have no MBID.
-    //         let handle = AppMachine::spawn_fetch_thread(&inner, &COLLECTION[3], fetch_tx);
-    //         handle.join().unwrap();
-
-    //         assert!(events_rx.try_recv().is_err());
-    //     }
-
-    //     #[test]
-    //     fn fetch_albums_event_disconnect() {
-    //         let mut mb_api = MockIMusicBrainz::new();
-
-    //         let arid: Mbid = "11111111-1111-1111-1111-111111111111".try_into().unwrap();
-
-    //         let (album_1, matches_1) = album_expectations_1();
-
-    //         let mut seq = Sequence::new();
-    //         search_release_group_expectation(&mut mb_api, &mut seq, &arid, &album_1, &matches_1);
-
-    //         let music_hoard = music_hoard(COLLECTION.to_owned());
-    //         let (events_tx, _) = event_channel();
-    //         let inner = AppInner::new(music_hoard, mb_api, events_tx);
-
-    //         let (fetch_tx, fetch_rx) = mpsc::channel();
-    //         // Use the second artist for this test.
-    //         let handle = AppMachine::spawn_fetch_thread(&inner, &COLLECTION[1], fetch_tx);
-    //         handle.join().unwrap();
-
-    //         let result = fetch_rx.try_recv().unwrap();
-    //         let expected = Ok(MatchStateInfo::Album(AlbumMatches {
-    //             matching: album_1.clone(),
-    //             list: matches_1.iter().cloned().map(Into::into).collect(),
-    //         }));
-    //         assert_eq!(result, expected);
-
-    //         assert_eq!(fetch_rx.try_recv().unwrap_err(), TryRecvError::Disconnected);
-    //     }
 
+    fn musicbrainz() -> MockIMusicBrainz {
+        MockIMusicBrainz::new()
+    }
+
+    fn job_channel() -> (JobSender, JobReceiver) {
+        let channel = JobChannel::new();
+        let sender = channel.sender();
+        let receiver = channel.receiver();
+        (sender, receiver)
+    }
+
+    fn event_sender() -> MockIFetchCompleteEventSender {
+        MockIFetchCompleteEventSender::new()
+    }
+
+    fn fetch_complete_expectation(event_sender: &mut MockIFetchCompleteEventSender, times: usize) {
+        event_sender
+            .expect_send_fetch_complete()
+            .times(times)
+            .returning(|| Ok(()));
+    }
+
+    fn daemon(job_receiver: JobReceiver) -> MusicBrainzDaemon {
+        MusicBrainzDaemon {
+            musicbrainz: Box::new(musicbrainz()),
+            job_receiver: job_receiver.receiver,
+            job_queue: JobQueue::new(),
+            event_sender: Box::new(event_sender()),
+        }
+    }
+
+    fn daemon_with(
+        musicbrainz: MockIMusicBrainz,
+        job_receiver: JobReceiver,
+        event_sender: MockIFetchCompleteEventSender,
+    ) -> MusicBrainzDaemon {
+        MusicBrainzDaemon {
+            musicbrainz: Box::new(musicbrainz),
+            job_receiver: job_receiver.receiver,
+            job_queue: JobQueue::new(),
+            event_sender: Box::new(event_sender),
+        }
+    }
+
+    fn search_artist_requests() -> VecDeque<MbParams> {
+        let artist = COLLECTION[3].meta.clone();
+        VecDeque::from([MbParams::search_artist(artist)])
+    }
+
+    fn artist_expectations() -> (ArtistMeta, Vec<Match<ArtistMeta>>) {
+        let artist = COLLECTION[3].meta.clone();
+
+        let artist_match_1 = Match::new(100, artist.clone());
+        let artist_match_2 = Match::new(50, artist.clone());
+        let matches = vec![artist_match_1.clone(), artist_match_2.clone()];
+
+        (artist, matches)
+    }
+
+    fn search_albums_requests() -> VecDeque<MbParams> {
+        let mbref = COLLECTION[1].meta.musicbrainz.as_ref();
+        let arid = mbref.unwrap().mbid().clone();
+
+        let album_1 = COLLECTION[1].albums[0].meta.clone();
+        let album_4 = COLLECTION[1].albums[3].meta.clone();
+
+        VecDeque::from([
+            MbParams::search_release_group(arid.clone(), album_1),
+            MbParams::search_release_group(arid.clone(), album_4),
+        ])
+    }
+
+    fn album_arid_expectation() -> Mbid {
+        let mbref = COLLECTION[1].meta.musicbrainz.as_ref();
+        mbref.unwrap().mbid().clone()
+    }
+
+    fn album_expectations_1() -> (AlbumMeta, Vec<Match<AlbumMeta>>) {
+        let album_1 = COLLECTION[1].albums[0].meta.clone();
+        let album_4 = COLLECTION[1].albums[3].meta.clone();
+
+        let album_match_1_1 = Match::new(100, album_1.clone());
+        let album_match_1_2 = Match::new(50, album_4.clone());
+        let matches_1 = vec![album_match_1_1.clone(), album_match_1_2.clone()];
+
+        (album_1, matches_1)
+    }
+
+    fn album_expectations_4() -> (AlbumMeta, Vec<Match<AlbumMeta>>) {
+        let album_1 = COLLECTION[1].albums[0].meta.clone();
+        let album_4 = COLLECTION[1].albums[3].meta.clone();
+
+        let album_match_4_1 = Match::new(100, album_4.clone());
+        let album_match_4_2 = Match::new(30, album_1.clone());
+        let matches_4 = vec![album_match_4_1.clone(), album_match_4_2.clone()];
+
+        (album_4, matches_4)
+    }
+
+    #[test]
+    fn enqueue_job_channel_disconnected() {
+        let (_, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Err(Error::JobChannelDisconnected));
+    }
+
+    #[test]
+    fn wait_for_job_channel_disconnected() {
+        let (_, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+        let result = daemon.wait_for_jobs();
+        assert_eq!(result, Err(Error::JobChannelDisconnected));
+    }
+
+    #[test]
+    fn enqueue_job_queue_empty() {
+        let (_job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+    }
+
+    #[test]
+    fn enqueue_job() {
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+
+        let requests = search_artist_requests();
+        let (result_sender, _) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests.clone());
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        assert_eq!(daemon.job_queue.pop_front().unwrap().requests, requests);
+    }
+
+    #[test]
+    fn wait_for_jobs_job() {
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+
+        let requests = search_artist_requests();
+        let (result_sender, _) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests.clone());
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.wait_for_jobs();
+        assert_eq!(result, Ok(()));
+
+        assert_eq!(daemon.job_queue.pop_front().unwrap().requests, requests);
+    }
+
+    #[test]
+    fn execute_empty() {
+        let (_job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon(job_receiver);
+
+        let (result_sender, _) = mpsc::channel();
+        let mut instance = JobInstance::new(result_sender, VecDeque::new());
+        let result = instance.execute_next(&mut musicbrainz(), &mut event_sender());
+        assert_eq!(result, Ok(JobInstanceStatus::Complete));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Err(JobError::JobQueueEmpty));
+    }
+
+    fn search_artist_expectation(
+        musicbrainz: &mut MockIMusicBrainz,
+        artist: &ArtistMeta,
+        matches: &[Match<ArtistMeta>],
+    ) {
+        let result = Ok(matches.to_owned());
+        musicbrainz
+            .expect_search_artist()
+            .with(predicate::eq(artist.clone()))
+            .times(1)
+            .return_once(|_| result);
+    }
+
+    #[test]
+    fn execute_search_artist() {
+        let mut musicbrainz = musicbrainz();
+        let (artist, matches) = artist_expectations();
+        search_artist_expectation(&mut musicbrainz, &artist, &matches);
+
+        let mut event_sender = event_sender();
+        fetch_complete_expectation(&mut event_sender, 1);
+
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon_with(musicbrainz, job_receiver, event_sender);
+
+        let requests = search_artist_requests();
+        let (result_sender, result_receiver) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests);
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Ok(()));
+
+        let result = result_receiver.try_recv().unwrap();
+        assert_eq!(result, Ok(MatchStateInfo::artist(artist, matches)));
+    }
+
+    fn search_release_group_expectation(
+        musicbrainz: &mut MockIMusicBrainz,
+        seq: &mut Sequence,
+        arid: &Mbid,
+        album: &AlbumMeta,
+        matches: &[Match<AlbumMeta>],
+    ) {
+        let result = Ok(matches.to_owned());
+        musicbrainz
+            .expect_search_release_group()
+            .with(predicate::eq(arid.clone()), predicate::eq(album.clone()))
+            .times(1)
+            .in_sequence(seq)
+            .return_once(|_, _| result);
+    }
+
+    #[test]
+    fn execute_search_release_groups() {
+        let mut musicbrainz = musicbrainz();
+        let arid = album_arid_expectation();
+        let (album_1, matches_1) = album_expectations_1();
+        let (album_4, matches_4) = album_expectations_4();
+
+        let mut seq = Sequence::new();
+        search_release_group_expectation(&mut musicbrainz, &mut seq, &arid, &album_1, &matches_1);
+        search_release_group_expectation(&mut musicbrainz, &mut seq, &arid, &album_4, &matches_4);
+
+        let mut event_sender = event_sender();
+        fetch_complete_expectation(&mut event_sender, 2);
+
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon_with(musicbrainz, job_receiver, event_sender);
+
+        let requests = search_albums_requests();
+        let (result_sender, result_receiver) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests);
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Ok(()));
+
+        let result = result_receiver.try_recv().unwrap();
+        assert_eq!(result, Ok(MatchStateInfo::album(album_1, matches_1)));
+
+        let result = result_receiver.try_recv().unwrap();
+        assert_eq!(result, Ok(MatchStateInfo::album(album_4, matches_4)));
+    }
+
+    #[test]
+    fn execute_search_release_groups_result_disconnect() {
+        let mut musicbrainz = musicbrainz();
+        let arid = album_arid_expectation();
+        let (album_1, matches_1) = album_expectations_1();
+
+        let mut seq = Sequence::new();
+        search_release_group_expectation(&mut musicbrainz, &mut seq, &arid, &album_1, &matches_1);
+
+        let mut event_sender = event_sender();
+        fetch_complete_expectation(&mut event_sender, 0);
+
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon_with(musicbrainz, job_receiver, event_sender);
+
+        let requests = search_albums_requests();
+        let (result_sender, _) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests);
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Ok(()));
+
+        // Two albums were submitted, but as one job. If the first one fails due to the
+        // result_channel disconnecting, all remaining requests in that job are dropped.
+        assert!(daemon.job_queue.pop_front().is_none());
+    }
+
+    #[test]
+    fn execute_search_artist_event_disconnect() {
+        let mut musicbrainz = musicbrainz();
+        let (artist, matches) = artist_expectations();
+        search_artist_expectation(&mut musicbrainz, &artist, &matches);
+
+        let mut event_sender = event_sender();
+        event_sender
+            .expect_send_fetch_complete()
+            .times(1)
+            .return_once(|| Err(EventError::Send(Event::FetchComplete)));
+
+        let (job_sender, job_receiver) = job_channel();
+        let mut daemon = daemon_with(musicbrainz, job_receiver, event_sender);
+
+        let requests = search_artist_requests();
+        let (result_sender, _result_receiver) = mpsc::channel();
+        let result = job_sender.submit_background_job(result_sender, requests);
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.enqueue_all_pending_jobs();
+        assert_eq!(result, Ok(()));
+
+        let result = daemon.execute_next_job();
+        assert_eq!(result, Err(JobError::EventChannelDisconnected));
+    }
+
+    #[test]
+    fn job_queue() {
+        let mut queue = JobQueue::new();
+        assert!(queue.is_empty());
+        assert_eq!(queue.foreground_queue.len(), 0);
+        assert_eq!(queue.background_queue.len(), 0);
+
+        let (result_sender, _) = mpsc::channel();
+        let bg = Job::new(
+            JobPriority::Background,
+            JobInstance::new(result_sender, VecDeque::new()),
+        );
+        queue.push_back(bg);
+
+        assert!(!queue.is_empty());
+        assert_eq!(queue.foreground_queue.len(), 0);
+        assert_eq!(queue.background_queue.len(), 1);
+
+        let (result_sender, _) = mpsc::channel();
+        let fg = Job::new(
+            JobPriority::Foreground,
+            JobInstance::new(result_sender, VecDeque::new()),
+        );
+        queue.push_back(fg);
+
+        assert!(!queue.is_empty());
+        assert_eq!(queue.foreground_queue.len(), 1);
+        assert_eq!(queue.background_queue.len(), 1);
+
+        let instance = queue.pop_front();
+        assert!(instance.is_some());
+        assert!(!queue.is_empty());
+        assert_eq!(queue.foreground_queue.len(), 0);
+        assert_eq!(queue.background_queue.len(), 1);
+
+        let instance = queue.pop_front();
+        assert!(instance.is_some());
+        assert!(queue.is_empty());
+        assert_eq!(queue.foreground_queue.len(), 0);
+        assert_eq!(queue.background_queue.len(), 0);
+
+        let instance = queue.pop_front();
+        assert!(instance.is_none());
+        assert!(queue.is_empty());
+    }
 }

src/tui/lib/interface/musicbrainz/daemon/mod.rs

@@ -7,6 +7,7 @@ use crate::tui::{app::MatchStateInfo, lib::interface::musicbrainz::api::Error as
 #[cfg(test)]
 use mockall::automock;
 
+#[derive(Debug, PartialEq, Eq)]
 pub enum Error {
     EventChannelDisconnected,
     JobChannelDisconnected,
@@ -33,23 +34,23 @@ pub trait IMbJobSender {
     ) -> Result<(), Error>;
 }
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub enum MbParams {
     Search(SearchParams),
 }
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub enum SearchParams {
     Artist(SearchArtistParams),
     ReleaseGroup(SearchReleaseGroupParams),
 }
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub struct SearchArtistParams {
     pub artist: ArtistMeta,
 }
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub struct SearchReleaseGroupParams {
     pub arid: Mbid,
     pub album: AlbumMeta,
@@ -67,3 +68,14 @@ impl MbParams {
         }))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn errors() {
+        assert!(!format!("{}", Error::EventChannelDisconnected).is_empty());
+        assert!(!format!("{}", Error::JobChannelDisconnected).is_empty());
+    }
+}