searcher: Remove the collector concept.

This patch removes the TopDocs collector class and adds a limit
argument on the search method.

src/lib.rs

@@ -14,7 +14,7 @@ use facet::Facet;
 use index::Index;
 use schema::Schema;
 use schemabuilder::SchemaBuilder;
-use searcher::{DocAddress, Searcher, TopDocs};
+use searcher::{DocAddress, Searcher};
 
 /// Python bindings for the search engine library Tantivy.
 ///
@@ -76,7 +76,6 @@ fn tantivy(_py: Python, m: &PyModule) -> PyResult<()> {
     m.add_class::<Document>()?;
     m.add_class::<Index>()?;
     m.add_class::<DocAddress>()?;
-    m.add_class::<TopDocs>()?;
     m.add_class::<Facet>()?;
     Ok(())
 }

src/searcher.rs

@@ -29,20 +29,25 @@ impl Searcher {
     /// search results.
     ///
     /// Raises a ValueError if there was an error with the search.
+    #[args(limit = 10)]
     fn search(
         &self,
+        py: Python,
         query: &Query,
-        collector: &mut TopDocs,
-    ) -> PyResult<Vec<(f32, DocAddress)>> {
-        let ret = self.inner.search(&query.inner, &collector.inner);
+        limit: usize,
+    ) -> PyResult<Vec<(PyObject, DocAddress)>> {
+        let collector = tv::collector::TopDocs::with_limit(limit);
+        let ret = self.inner.search(&query.inner, &collector);
+
         match ret {
             Ok(r) => {
-                let result: Vec<(f32, DocAddress)> =
-                    r.iter().map(|(f, d)| (*f, DocAddress::from(d))).collect();
+                let result: Vec<(PyObject, DocAddress)> =
+                    r.iter().map(|(f, d)| ((*f).into_py(py), DocAddress::from(d))).collect();
                 Ok(result)
             }
             Err(e) => Err(exceptions::ValueError::py_err(e.to_string())),
         }
+
     }
 
     /// Returns the overall number of documents in the index.
@@ -110,28 +115,6 @@ impl Into<tv::DocAddress> for &DocAddress {
     }
 }
 
-/// The Top Score Collector keeps track of the K documents sorted by their
-/// score.
-///
-/// Args:
-///     limit (int, optional): The number of documents that the top scorer will
-///         retrieve. Must be a positive integer larger than 0. Defaults to 10.
-#[pyclass]
-pub(crate) struct TopDocs {
-    inner: tv::collector::TopDocs,
-}
-
-#[pymethods]
-impl TopDocs {
-    #[new]
-    #[args(limit = 10)]
-    fn new(obj: &PyRawObject, limit: usize) -> PyResult<()> {
-        let top = tv::collector::TopDocs::with_limit(limit);
-        obj.init(TopDocs { inner: top });
-        Ok(())
-    }
-}
-
 #[pyproto]
 impl PyObjectProtocol for Searcher {
     fn __repr__(&self) -> PyResult<String> {

tests/tantivy_test.py

@@ -76,9 +76,7 @@ class TestClass(object):
         _, index = dir_index
         query = index.parse_query("sea whale", ["title", "body"])
 
-        top_docs = tantivy.TopDocs(10)
-
-        result = index.searcher().search(query, top_docs)
+        result = index.searcher().search(query, 10)
         assert len(result) == 1
 
     def test_simple_search_after_reuse(self, dir_index):
@@ -86,18 +84,14 @@ class TestClass(object):
         index = Index(schema(), str(index_dir))
         query = index.parse_query("sea whale", ["title", "body"])
 
-        top_docs = tantivy.TopDocs(10)
-
-        result = index.searcher().search(query, top_docs)
+        result = index.searcher().search(query, 10)
         assert len(result) == 1
 
     def test_simple_search_in_ram(self, ram_index):
         index = ram_index
         query = index.parse_query("sea whale", ["title", "body"])
 
-        top_docs = tantivy.TopDocs(10)
-
-        result = index.searcher().search(query, top_docs)
+        result = index.searcher().search(query, 10)
         assert len(result) == 1
         _, doc_address = result[0]
         searched_doc = index.searcher().doc(doc_address)
@@ -107,15 +101,14 @@ class TestClass(object):
         index = ram_index
         query = index.parse_query("title:men AND body:summer", default_field_names=["title", "body"])
         # look for an intersection of documents
-        top_docs = tantivy.TopDocs(10)
         searcher = index.searcher()
-        result = searcher.search(query, top_docs)
+        result = searcher.search(query, 10)
 
         # summer isn't present
         assert len(result) == 0
 
         query = index.parse_query("title:men AND body:winter", ["title", "body"])
-        result = searcher.search(query, top_docs)
+        result = searcher.search(query)
 
         assert len(result) == 1
 
@@ -142,8 +135,7 @@ class TestClass(object):
 class TestUpdateClass(object):
     def test_delete_update(self, ram_index):
         query = ram_index.parse_query("Frankenstein", ["title"])
-        top_docs = tantivy.TopDocs(10)
-        result = ram_index.searcher().search(query, top_docs)
+        result = ram_index.searcher().search(query, 10)
         assert len(result) == 1
 
         writer = ram_index.writer()
@@ -158,7 +150,7 @@ class TestUpdateClass(object):
         writer.commit()
         ram_index.reload()
 
-        result = ram_index.searcher().search(query, top_docs)
+        result = ram_index.searcher().search(query)
         assert len(result) == 0