feat: Support query words concatenation

This commit is contained in:
Clément Renault 2019-06-26 16:28:51 +02:00
parent 1b0fd2e0ba
commit 9f320590d3
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@ -22,18 +22,17 @@ const NGRAMS: usize = 3;
struct Automaton {
index: usize,
is_synonym: bool,
number_words: usize,
is_exact: bool,
dfa: DfaExt,
}
impl Automaton {
fn synonym(index: usize, number_words: usize, dfa: DfaExt) -> Automaton {
Automaton { index, is_synonym: true, number_words, dfa }
fn exact(index: usize, dfa: DfaExt) -> Automaton {
Automaton { index, is_exact: true, dfa }
}
fn original(index: usize, number_words: usize, dfa: DfaExt) -> Automaton {
Automaton { index, is_synonym: false, number_words, dfa }
fn non_exact(index: usize, dfa: DfaExt) -> Automaton {
Automaton { index, is_exact: false, dfa }
}
}
@ -58,17 +57,24 @@ fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton
let mut index = 0;
let mut ngrams = query_words.windows(n).peekable();
while let Some(ngram) = ngrams.next() {
let ngram_nb_words = ngram.len();
let ngram = ngram.join(" ");
while let Some(ngram_slice) = ngrams.next() {
let ngram_nb_words = ngram_slice.len();
let ngram = ngram_slice.join(" ");
let concat = ngram_slice.concat();
// automaton of concatenation of query words
let normalized = normalize_str(&concat);
let lev = build_dfa(&normalized);
let automaton = Automaton::exact(index, lev);
automatons.push((automaton, normalized));
let has_following_word = ngrams.peek().is_some();
let not_prefix_dfa = has_following_word || has_end_whitespace || ngram.chars().all(is_cjk);
let lev = {
let normalized = normalize_str(&ngram);
if not_prefix_dfa { build_dfa(&normalized) } else { build_prefix_dfa(&normalized) }
};
// automaton of synonyms of the ngrams
let normalized = normalize_str(&ngram);
let lev = if not_prefix_dfa { build_dfa(&normalized) } else { build_prefix_dfa(&normalized) };
let mut stream = synonyms.search(&lev).into_stream();
while let Some(base) = stream.next() {
@ -82,12 +88,16 @@ fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton
let mut stream = synonyms.into_stream();
while let Some(synonyms) = stream.next() {
let synonyms = std::str::from_utf8(synonyms).unwrap();
let nb_synonym_words = split_query_string(synonyms).count();
for synonym in split_query_string(synonyms) {
let lev = build_dfa(synonym);
let automaton = Automaton::synonym(index, nb_synonym_words, lev);
let automaton = if nb_synonym_words == 1 {
Automaton::exact(index, lev)
} else {
Automaton::non_exact(index, lev)
};
automatons.push((automaton, synonym.to_owned()));
}
}
@ -96,7 +106,7 @@ fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton
if n == 1 {
let lev = if not_prefix_dfa { build_dfa(&ngram) } else { build_prefix_dfa(&ngram) };
let automaton = Automaton::original(index, ngram_nb_words, lev);
let automaton = Automaton::exact(index, lev);
automatons.push((automaton, ngram));
}
@ -174,9 +184,9 @@ where S: Store,
while let Some((input, indexed_values)) = stream.next() {
for iv in indexed_values {
let Automaton { index, is_synonym, number_words, ref dfa } = automatons[iv.index];
let Automaton { index, is_exact, ref dfa } = automatons[iv.index];
let distance = dfa.eval(input).to_u8();
let is_exact = (is_synonym && number_words == 1) || (!is_synonym && distance == 0 && input.len() == dfa.query_len());
let is_exact = is_exact && distance == 0 && input.len() == dfa.query_len();
let doc_indexes = self.store.word_indexes(input)?;
let doc_indexes = match doc_indexes {
@ -1023,7 +1033,30 @@ mod tests {
});
assert_matches!(iter.next(), Some(Document { id: DocumentId(1), matches }) => {
let mut iter = matches.into_iter();
assert_matches!(iter.next(), Some(Match { query_index: 0, .. }));
assert_matches!(iter.next(), Some(Match { query_index: 0, distance: 0, .. })); // téléphone
assert_matches!(iter.next(), Some(Match { query_index: 0, distance: 1, .. })); // telephone
assert_matches!(iter.next(), Some(Match { query_index: 0, distance: 2, .. })); // télephone
assert_matches!(iter.next(), None);
});
assert_matches!(iter.next(), None);
}
#[test]
fn simple_concatenation() {
let store = InMemorySetStore::from_iter(vec![
("iphone", &[doc_index(0, 0)][..]),
("case", &[doc_index(0, 1)][..]),
]);
let builder = QueryBuilder::new(&store);
let results = builder.query("i phone case", 0..20).unwrap();
let mut iter = results.into_iter();
assert_matches!(iter.next(), Some(Document { id: DocumentId(0), matches }) => {
let mut iter = matches.into_iter();
assert_matches!(iter.next(), Some(Match { query_index: 0, word_index: 0, distance: 0, .. })); // iphone
assert_matches!(iter.next(), Some(Match { query_index: 1, word_index: 0, distance: 1, .. })); // phone
assert_matches!(iter.next(), Some(Match { query_index: 2, word_index: 1, distance: 0, .. })); // case
assert_matches!(iter.next(), None);
});
assert_matches!(iter.next(), None);