bass-foundry/plugins/rivet/core/tests/musical.rs

use rivet_core::*;

fn rhythm(p: &Phrase) -> Vec<(u32, u32)> {
    p.notes.iter().map(|n| (n.start, n.duration)).collect()
}
fn options(motif: &Phrase, role: Role, s: &Settings) -> Vec<Candidate> {
    realize(motif, role, 2, 2 * BAR, false, 0, s, &Harmony::default()).unwrap()
}
#[test]
fn each_role_offers_distinct_reproducible_options_led_by_its_best_fit() {
    let motif = demo_motif();
    let s = Settings::default();
    for (role, first) in [
        (Role::Statement, Strategy::Quote),
        (Role::Answer, Strategy::CallResponse),
        (Role::Departure, Strategy::LaterPeak),
        (Role::Return, Strategy::HarmonicReturn),
    ] {
        let a = options(&motif, role, &s);
        assert_eq!(a, options(&motif, role, &s), "{role:?} is deterministic");
        assert_eq!(a.len(), 3, "{role:?}");
        assert_eq!(a[0].strategy, first, "{role:?}");
        for pair in a.windows(2) {
            assert_ne!(pair[0].phrase, pair[1].phrase);
        }
        for c in &a {
            c.phrase.validate(MAX_PLAYBACK_NOTES).unwrap();
            assert_eq!(c.phrase.length, 2 * BAR);
        }
    }
    let quote = &options(&motif, Role::Statement, &s)[0];
    assert_eq!(
        quote.phrase.notes, motif.notes,
        "a statement quotes the motif"
    );
    let rest = realize(&motif, Role::Rest, 1, 0, false, 0, &s, &Harmony::default()).unwrap();
    assert_eq!(rest.len(), 1);
    assert!(rest[0].phrase.notes.is_empty());
}
#[test]
fn options_change_rhythm_and_density_not_only_pitch() {
    let motif = demo_motif();
    let s = Settings::default();
    let mut signatures = std::collections::BTreeSet::new();
    for seed in 0..12 {
        for role in [Role::Answer, Role::Departure] {
            for c in options(&motif, role, &Settings { seed, ..s.clone() }) {
                signatures.insert(rhythm(&c.phrase));
            }
        }
    }
    assert!(
        signatures.len() > 3,
        "seeds should explore rhythmic decisions"
    );
    assert!(options(&motif, Role::Answer, &s)
        .iter()
        .any(|c| c.phrase.notes.len() != motif.notes.len()));
}
#[test]
fn fixed_groove_and_separate_note_locks_take_priority() {
    let mut motif = demo_motif();
    motif.notes[1].pitch_locked = true;
    motif.notes[1].pitch = 99;
    motif.notes[3].rhythm_locked = true;
    for role in [Role::Answer, Role::Departure, Role::Return] {
        for c in realize(
            &motif,
            role,
            4,
            0,
            false,
            0,
            &Settings::default(),
            &Harmony::default(),
        )
        .unwrap()
        {
            let locked: Vec<_> = c.phrase.notes.iter().filter(|n| n.pitch_locked).collect();
            assert_eq!(locked.len(), 2, "{role:?} {:?}", c.strategy);
            assert!(locked.iter().all(|n| n.pitch == 99));
            for rep in 0..2 {
                assert!(c.phrase.notes.iter().any(|n| n.rhythm_locked
                    && n.start == motif.notes[3].start + rep * motif.length
                    && n.duration == motif.notes[3].duration));
            }
        }
    }
    let motif = demo_motif();
    let s = Settings {
        preserve_rhythm: true,
        ..Settings::default()
    };
    for c in options(&motif, Role::Departure, &s) {
        assert_eq!(rhythm(&c.phrase), rhythm(&motif));
    }
}
#[test]
fn fully_locked_motif_returns_one_honest_option() {
    let mut motif = demo_motif();
    for n in &mut motif.notes {
        n.locked = true;
    }
    let all = options(&motif, Role::Answer, &Settings::default());
    assert_eq!(all.len(), 1);
    assert_eq!(all[0].phrase.notes, motif.notes);
}
#[test]
fn harmony_drives_strong_notes_and_the_final_ending() {
    let harmony = Harmony {
        length: BAR,
        spans: vec![HarmonySpan {
            start: 0,
            duration: BAR,
            tones: ChordQuality::Major.mask(0),
            bass: 48,
        }],
    };
    for ending in [Ending::Open, Ending::Resolve] {
        let s = Settings {
            preserve_contour: false,
            ending,
            ..Settings::default()
        };
        for c in realize(
            &demo_motif(),
            Role::Return,
            2,
            6 * BAR,
            true,
            0,
            &s,
            &harmony,
        )
        .unwrap()
        {
            if c.strategy == Strategy::Quote {
                continue;
            }
            let last = c.phrase.notes.last().unwrap();
            let chord = ChordQuality::Major.mask(0) & (1 << (last.pitch % 12)) != 0;
            assert_eq!(chord, ending == Ending::Resolve, "{:?}", c.strategy);
            for n in c
                .phrase
                .notes
                .iter()
                .filter(|n| n.start.is_multiple_of(PPQ) && n.start != last.start)
            {
                assert_ne!(
                    harmony.at(n.start).unwrap().tones & (1 << (n.pitch % 12)),
                    0
                );
            }
        }
    }
}
#[test]
fn imported_harmony_preserves_voicings_and_gaps_without_guessing_roots() {
    let notes: Vec<_> = [64, 67, 72]
        .into_iter()
        .map(|pitch| Note {
            start: 0,
            duration: BAR,
            pitch,
            velocity: 90,
            ..Default::default()
        })
        .collect();
    let h = Harmony::from_midi(&notes, 2 * BAR).unwrap();
    assert_eq!(h.spans.len(), 1);
    assert_eq!(h.spans[0].bass, 64);
    assert_eq!(h.spans[0].tones, ChordQuality::Major.mask(0));
    assert!(h.at(BAR + 1).is_none());
    assert_eq!(h.at(2 * BAR).unwrap().bass, 64);
}
#[test]
fn every_meter_key_and_block_length_realizes_valid_options() {
    let motif = demo_motif();
    for meter in Meter::ALL {
        for root in [0, 5, 11] {
            for scale in Scale::ALL {
                let s = Settings {
                    root,
                    scale,
                    meter,
                    low: 60,
                    high: 72,
                    ..Settings::default()
                };
                for bars in [1, 3, 8] {
                    for role in Role::ALL {
                        for c in realize(&motif, role, bars, 0, true, 0, &s, &Harmony::default())
                            .unwrap()
                        {
                            c.phrase.check(MAX_PLAYBACK_NOTES, true).unwrap();
                            assert_eq!(c.phrase.length, bars as u32 * meter.bar());
                        }
                    }
                }
            }
        }
    }
}