1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133

use crate::core::Searcher;
use crate::core::SegmentReader;
use crate::docset::DocSet;
use crate::query::explanation::does_not_match;
use crate::query::{Explanation, Query, Scorer, Weight};
use crate::DocId;
use crate::Result;
use crate::Score;

/// Query that matches all of the documents.
///
/// All of the document get the score 1f32.
#[derive(Clone, Debug)]
pub struct AllQuery;

impl Query for AllQuery {
    fn weight(&self, _: &Searcher, _: bool) -> Result<Box<dyn Weight>> {
        Ok(Box::new(AllWeight))
    }
}

/// Weight associated to the `AllQuery` query.
pub struct AllWeight;

impl Weight for AllWeight {
    fn scorer(&self, reader: &SegmentReader) -> Result<Box<dyn Scorer>> {
        Ok(Box::new(AllScorer {
            state: State::NotStarted,
            doc: 0u32,
            max_doc: reader.max_doc(),
        }))
    }

    fn explain(&self, reader: &SegmentReader, doc: DocId) -> Result<Explanation> {
        if doc >= reader.max_doc() {
            return Err(does_not_match(doc));
        }
        Ok(Explanation::new("AllQuery", 1f32))
    }
}

enum State {
    NotStarted,
    Started,
    Finished,
}

/// Scorer associated to the `AllQuery` query.
pub struct AllScorer {
    state: State,
    doc: DocId,
    max_doc: DocId,
}

impl DocSet for AllScorer {
    fn advance(&mut self) -> bool {
        match self.state {
            State::NotStarted => {
                self.state = State::Started;
                self.doc = 0;
            }
            State::Started => {
                self.doc += 1u32;
            }
            State::Finished => {
                return false;
            }
        }
        if self.doc < self.max_doc {
            true
        } else {
            self.state = State::Finished;
            false
        }
    }

    fn doc(&self) -> DocId {
        self.doc
    }

    fn size_hint(&self) -> u32 {
        self.max_doc
    }
}

impl Scorer for AllScorer {
    fn score(&mut self) -> Score {
        1f32
    }
}

#[cfg(test)]
mod tests {

    use super::AllQuery;
    use crate::query::Query;
    use crate::schema::{Schema, TEXT};
    use crate::Index;

    #[test]
    fn test_all_query() {
        let mut schema_builder = Schema::builder();
        let field = schema_builder.add_text_field("text", TEXT);
        let schema = schema_builder.build();
        let index = Index::create_in_ram(schema);
        let mut index_writer = index.writer_with_num_threads(1, 10_000_000).unwrap();
        index_writer.add_document(doc!(field=>"aaa"));
        index_writer.add_document(doc!(field=>"bbb"));
        index_writer.commit().unwrap();
        index_writer.add_document(doc!(field=>"ccc"));
        index_writer.commit().unwrap();
        let reader = index.reader().unwrap();
        reader.reload().unwrap();
        let searcher = reader.searcher();
        let weight = AllQuery.weight(&searcher, false).unwrap();
        {
            let reader = searcher.segment_reader(0);
            let mut scorer = weight.scorer(reader).unwrap();
            assert!(scorer.advance());
            assert_eq!(scorer.doc(), 0u32);
            assert!(scorer.advance());
            assert_eq!(scorer.doc(), 1u32);
            assert!(!scorer.advance());
        }
        {
            let reader = searcher.segment_reader(1);
            let mut scorer = weight.scorer(reader).unwrap();
            assert!(scorer.advance());
            assert_eq!(scorer.doc(), 0u32);
            assert!(!scorer.advance());
        }
    }
}