Updated changelog

Leave a defensive versioned footer check to make sure we add new logic handling
when we add possible footer versions

Restricted VersionedFooter::from_bytes to be used inside the crate only

remove a half-baked test

CHANGELOG.md

@@ -1,17 +1,3 @@
-Tantivy 0.11.3
-=======================
-- Fixed DateTime as a fast field (#735)
-
-Tantivy 0.11.2
-=======================
-- The future returned by `IndexWriter::merge` does not borrow `self` mutably anymore (#732)
-- Exposing a constructor for `WatchHandle` (#731)
-
-Tantivy 0.11.1
-=====================
-- Bug fix #729
-
-
 Tantivy 0.11.0
 =====================
 
@@ -23,7 +9,6 @@ Tantivy 0.11.0
 - API change around `Box<BoxableTokenizer>`. See detail in #629
 - Avoid rebuilding Regex automaton whenever a regex query is reused. #639 (@brainlock)
 - Add footer with some metadata to index files. #605 (@fdb-hiroshima)
-- Add a method to check the compatibility of the footer in the index with the running version of tantivy (@petr-tik)
 - TopDocs collector: ensure stable sorting on equal score. #671 (@brainlock)
 - Added handling of pre-tokenized text fields (#642), which will enable users to
   load tokens created outside tantivy. See usage in examples/pre_tokenized_text. (@kkoziara)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tantivy"
-version = "0.11.3"
+version = "0.11.0"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 license = "MIT"
 categories = ["database-implementations", "data-structures"]
@@ -33,6 +33,7 @@ fs2={version="0.4", optional=true}
 itertools = "0.8"
 levenshtein_automata = {version="0.1", features=["fst_automaton"]}
 notify = {version="4", optional=true}
+bit-set = "0.5"
 uuid = { version = "0.8", features = ["v4", "serde"] }
 crossbeam = "0.7"
 futures = {version = "0.3",  features=["thread-pool"] }
@@ -40,7 +41,7 @@ owning_ref = "0.4"
 stable_deref_trait = "1.0.0"
 rust-stemmers = "1.2"
 downcast-rs = { version="1.0" }
-tantivy-query-grammar = { version="0.11", path="./query-grammar" }
+tantivy-query-grammar = { path="./query-grammar" }
 bitpacking = {version="0.8", default-features = false, features=["bitpacker4x"]}
 census = "0.4"
 fnv = "1.0.6"

examples/faceted_search.rs

@@ -13,100 +13,63 @@
 // ---
 // Importing tantivy...
 use tantivy::collector::FacetCollector;
-use tantivy::query::{AllQuery, TermQuery};
+use tantivy::query::AllQuery;
 use tantivy::schema::*;
 use tantivy::{doc, Index};
+use tempfile::TempDir;
 
 fn main() -> tantivy::Result<()> {
-    // Let's create a temporary directory for the sake of this example
+    // Let's create a temporary directory for the
+    // sake of this example
+    let index_path = TempDir::new()?;
     let mut schema_builder = Schema::builder();
 
-    let name = schema_builder.add_text_field("felin_name", TEXT | STORED);
-    // this is our faceted field: its scientific classification
-    let classification = schema_builder.add_facet_field("classification");
+    schema_builder.add_text_field("name", TEXT | STORED);
+
+    // this is our faceted field
+    schema_builder.add_facet_field("tags");
 
     let schema = schema_builder.build();
-    let index = Index::create_in_ram(schema);
 
-    let mut index_writer = index.writer(30_000_000)?;
+    let index = Index::create_in_dir(&index_path, schema.clone())?;
+
+    let mut index_writer = index.writer(50_000_000)?;
+
+    let name = schema.get_field("name").unwrap();
+    let tags = schema.get_field("tags").unwrap();
 
     // For convenience, tantivy also comes with a macro to
     // reduce the boilerplate above.
     index_writer.add_document(doc!(
-        name => "Cat",
-        classification => Facet::from("/Felidae/Felinae/Felis")
+        name => "the ditch",
+        tags => Facet::from("/pools/north")
     ));
+
     index_writer.add_document(doc!(
-        name => "Canada lynx",
-        classification => Facet::from("/Felidae/Felinae/Lynx")
-    ));
-    index_writer.add_document(doc!(
-        name => "Cheetah",
-        classification => Facet::from("/Felidae/Felinae/Acinonyx")
-    ));
-    index_writer.add_document(doc!(
-        name => "Tiger",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Lion",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Jaguar",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Sunda clouded leopard",
-        classification => Facet::from("/Felidae/Pantherinae/Neofelis")
-    ));
-    index_writer.add_document(doc!(
-        name => "Fossa",
-        classification => Facet::from("/Eupleridae/Cryptoprocta")
+        name => "little stacey",
+        tags => Facet::from("/pools/south")
     ));
+
     index_writer.commit()?;
 
     let reader = index.reader()?;
+
     let searcher = reader.searcher();
-    {
-        let mut facet_collector = FacetCollector::for_field(classification);
-        facet_collector.add_facet("/Felidae");
-        let facet_counts = searcher.search(&AllQuery, &facet_collector)?;
-        // This lists all of the facet counts, right below "/Felidae".
-        let facets: Vec<(&Facet, u64)> = facet_counts.get("/Felidae").collect();
-        assert_eq!(
-            facets,
-            vec![
-                (&Facet::from("/Felidae/Felinae"), 3),
-                (&Facet::from("/Felidae/Pantherinae"), 4),
-            ]
-        );
-    }
 
-    // Facets are also searchable.
-    //
-    // For instance a common UI pattern is to allow the user someone to click on a facet link
-    // (e.g: `Pantherinae`) to drill down and filter the current result set with this subfacet.
-    //
-    // The search would then look as follows.
+    let mut facet_collector = FacetCollector::for_field(tags);
+    facet_collector.add_facet("/pools");
 
-    // Check the reference doc for different ways to create a `Facet` object.
-    {
-        let facet = Facet::from_text("/Felidae/Pantherinae");
-        let facet_term = Term::from_facet(classification, &facet);
-        let facet_term_query = TermQuery::new(facet_term, IndexRecordOption::Basic);
-        let mut facet_collector = FacetCollector::for_field(classification);
-        facet_collector.add_facet("/Felidae/Pantherinae");
-        let facet_counts = searcher.search(&facet_term_query, &facet_collector)?;
-        let facets: Vec<(&Facet, u64)> = facet_counts.get("/Felidae/Pantherinae").collect();
-        assert_eq!(
-            facets,
-            vec![
-                (&Facet::from("/Felidae/Pantherinae/Neofelis"), 1),
-                (&Facet::from("/Felidae/Pantherinae/Panthera"), 3),
-            ]
-        );
-    }
+    let facet_counts = searcher.search(&AllQuery, &facet_collector).unwrap();
+
+    // This lists all of the facet counts
+    let facets: Vec<(&Facet, u64)> = facet_counts.get("/pools").collect();
+    assert_eq!(
+        facets,
+        vec![
+            (&Facet::from("/pools/north"), 1),
+            (&Facet::from("/pools/south"), 1),
+        ]
+    );
 
     Ok(())
 }

query-grammar/README.md

@@ -1,3 +0,0 @@
-# Tantivy Query Grammar
-
-This crate is used by tantivy to parse queries.

src/collector/facet_collector.rs

@@ -452,11 +452,9 @@ impl FacetCounts {
 #[cfg(test)]
 mod tests {
     use super::{FacetCollector, FacetCounts};
-    use crate::collector::Count;
     use crate::core::Index;
-    use crate::query::{AllQuery, QueryParser, TermQuery};
-    use crate::schema::{Document, Facet, Field, IndexRecordOption, Schema};
-    use crate::Term;
+    use crate::query::AllQuery;
+    use crate::schema::{Document, Facet, Field, Schema};
     use rand::distributions::Uniform;
     use rand::prelude::SliceRandom;
     use rand::{thread_rng, Rng};
@@ -546,56 +544,6 @@ mod tests {
         assert_eq!(facets[0].1, 1);
     }
 
-    #[test]
-    fn test_doc_search_by_facet() {
-        let mut schema_builder = Schema::builder();
-        let facet_field = schema_builder.add_facet_field("facet");
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/A"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/B"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/C/A"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/D/C/A"),
-        ));
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let searcher = reader.searcher();
-        assert_eq!(searcher.num_docs(), 4);
-
-        let count_facet = |facet_str: &str| {
-            let term = Term::from_facet(facet_field, &Facet::from_text(facet_str));
-            searcher
-                .search(&TermQuery::new(term, IndexRecordOption::Basic), &Count)
-                .unwrap()
-        };
-
-        assert_eq!(count_facet("/"), 4);
-        assert_eq!(count_facet("/A"), 3);
-        assert_eq!(count_facet("/A/B"), 1);
-        assert_eq!(count_facet("/A/C"), 1);
-        assert_eq!(count_facet("/A/C/A"), 1);
-        assert_eq!(count_facet("/C/A"), 0);
-        {
-            let query_parser = QueryParser::for_index(&index, vec![]);
-            {
-                let query = query_parser.parse_query("facet:/A/B").unwrap();
-                assert_eq!(1, searcher.search(&query, &Count).unwrap());
-            }
-            {
-                let query = query_parser.parse_query("facet:/A").unwrap();
-                assert_eq!(3, searcher.search(&query, &Count).unwrap());
-            }
-        }
-    }
-
     #[test]
     fn test_non_used_facet_collector() {
         let mut facet_collector = FacetCollector::for_field(Field::from_field_id(0));

src/common/composite_file.rs

@@ -186,7 +186,7 @@ mod test {
     use super::{CompositeFile, CompositeWrite};
     use crate::common::BinarySerializable;
     use crate::common::VInt;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory};
+    use crate::directory::{Directory, RAMDirectory};
     use crate::schema::Field;
     use std::io::Write;
     use std::path::Path;

src/core/index.rs

@@ -338,7 +338,7 @@ impl Index {
 
     /// Creates a new segment.
     pub fn new_segment(&self) -> Segment {
-        let mut segment_meta = self
+        let segment_meta = self
             .inventory
             .new_segment_meta(SegmentId::generate_random(), 0);
         self.segment(segment_meta)

src/core/index_meta.rs

@@ -35,7 +35,6 @@ impl SegmentMetaInventory {
             segment_id,
             max_doc,
             deletes: None,
-            bundled: false,
         };
         SegmentMeta::from(self.inventory.track(inner))
     }
@@ -82,19 +81,6 @@ impl SegmentMeta {
         self.tracked.segment_id
     }
 
-    pub fn with_bundled(self) -> SegmentMeta {
-        SegmentMeta::from(self.tracked.map(|inner| InnerSegmentMeta {
-            segment_id: inner.segment_id,
-            max_doc: inner.max_doc,
-            deletes: inner.deletes.clone(),
-            bundled: true,
-        }))
-    }
-
-    pub fn is_bundled(&self) -> bool {
-        self.tracked.bundled
-    }
-
     /// Returns the number of deleted documents.
     pub fn num_deleted_docs(&self) -> u32 {
         self.tracked
@@ -121,12 +107,8 @@ impl SegmentMeta {
     /// It just joins the segment id with the extension
     /// associated to a segment component.
     pub fn relative_path(&self, component: SegmentComponent) -> PathBuf {
-        let suffix = self.suffix(component);
-        self.relative_path_from_suffix(&suffix)
-    }
-
-    fn suffix(&self, component: SegmentComponent) -> String {
-        match component {
+        let mut path = self.id().uuid_string();
+        path.push_str(&*match component {
             SegmentComponent::POSTINGS => ".idx".to_string(),
             SegmentComponent::POSITIONS => ".pos".to_string(),
             SegmentComponent::POSITIONSSKIP => ".posidx".to_string(),
@@ -135,17 +117,7 @@ impl SegmentMeta {
             SegmentComponent::FASTFIELDS => ".fast".to_string(),
             SegmentComponent::FIELDNORMS => ".fieldnorm".to_string(),
             SegmentComponent::DELETE => format!(".{}.del", self.delete_opstamp().unwrap_or(0)),
-        }
-    }
-
-    /// Returns the relative path of a component of our segment.
-    ///
-    /// It just joins the segment id with the extension
-    /// associated to a segment component.
-    pub fn relative_path_from_suffix(&self, suffix: &str) -> PathBuf {
-        let mut path = self.id().uuid_string();
-        path.push_str(".");
-        path.push_str(&suffix);
+        });
         PathBuf::from(path)
     }
 
@@ -189,7 +161,6 @@ impl SegmentMeta {
             segment_id: inner_meta.segment_id,
             max_doc,
             deletes: None,
-            bundled: inner_meta.bundled,
         });
         SegmentMeta { tracked }
     }
@@ -204,7 +175,6 @@ impl SegmentMeta {
             segment_id: inner_meta.segment_id,
             max_doc: inner_meta.max_doc,
             deletes: Some(delete_meta),
-            bundled: inner_meta.bundled,
         });
         SegmentMeta { tracked }
     }
@@ -215,7 +185,6 @@ struct InnerSegmentMeta {
     segment_id: SegmentId,
     max_doc: u32,
     deletes: Option<DeleteMeta>,
-    bundled: bool,
 }
 
 impl InnerSegmentMeta {

src/core/segment.rs

@@ -4,12 +4,14 @@ use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::directory::error::{OpenReadError, OpenWriteError};
 use crate::directory::Directory;
-use crate::directory::{ReadOnlyDirectory, ReadOnlySource, WritePtr};
+use crate::directory::{ReadOnlySource, WritePtr};
 use crate::indexer::segment_serializer::SegmentSerializer;
 use crate::schema::Schema;
 use crate::Opstamp;
+use crate::Result;
 use std::fmt;
 use std::path::PathBuf;
+use std::result;
 
 /// A segment is a piece of the index.
 #[derive(Clone)]
@@ -81,30 +83,23 @@ impl Segment {
     }
 
     /// Open one of the component file for a *regular* read.
-    pub fn open_read(&self, component: SegmentComponent) -> Result<ReadOnlySource, OpenReadError> {
+    pub fn open_read(
+        &self,
+        component: SegmentComponent,
+    ) -> result::Result<ReadOnlySource, OpenReadError> {
         let path = self.relative_path(component);
         let source = self.index.directory().open_read(&path)?;
         Ok(source)
     }
 
     /// Open one of the component file for *regular* write.
-    pub fn open_write(&mut self, component: SegmentComponent) -> Result<WritePtr, OpenWriteError> {
-        let path = self.relative_path(component);
-        self.index.directory_mut().open_write(&path)
-    }
-
-    pub fn open_bundle_writer(&mut self) -> Result<WritePtr, OpenWriteError> {
-        let path = self.meta.relative_path_from_suffix("bundle");
-        self.index.directory_mut().open_write(&path)
-    }
-
-    pub(crate) fn open_write_in_directory(
+    pub fn open_write(
         &mut self,
         component: SegmentComponent,
-        directory: &mut dyn Directory,
-    ) -> Result<WritePtr, OpenWriteError> {
+    ) -> result::Result<WritePtr, OpenWriteError> {
         let path = self.relative_path(component);
-        directory.open_write(&path)
+        let write = self.index.directory_mut().open_write(&path)?;
+        Ok(write)
     }
 }
 
@@ -114,5 +109,5 @@ pub trait SerializableSegment {
     ///
     /// # Returns
     /// The number of documents in the segment.
-    fn write(&self, serializer: SegmentSerializer) -> crate::Result<u32>;
+    fn write(&self, serializer: SegmentSerializer) -> Result<u32>;
 }

src/directory/bundle_directory.rs

@@ -1,97 +0,0 @@
-use crate::directory::directory::ReadOnlyDirectory;
-use crate::directory::error::OpenReadError;
-use crate::directory::ReadOnlySource;
-use crate::error::DataCorruption;
-use std::collections::HashMap;
-use std::path::{Path, PathBuf};
-use std::sync::Arc;
-
-#[derive(Clone)]
-struct BundleDirectory {
-    source_map: Arc<HashMap<PathBuf, ReadOnlySource>>,
-}
-
-impl BundleDirectory {
-    pub fn from_source(source: ReadOnlySource) -> Result<BundleDirectory, DataCorruption> {
-        let mut index_offset_buf = [0u8; 8];
-        let (body_idx, footer_offset) = source.split_from_end(8);
-        index_offset_buf.copy_from_slice(footer_offset.as_slice());
-        let offset = u64::from_le_bytes(index_offset_buf);
-        let (body_source, idx_source) = body_idx.split(offset as usize);
-        let idx: HashMap<PathBuf, (u64, u64)> = serde_json::from_slice(idx_source.as_slice())
-            .map_err(|err| {
-                let msg = format!("Failed to read index from bundle. {:?}", err);
-                DataCorruption::comment_only(msg)
-            })?;
-        let source_map: HashMap<PathBuf, ReadOnlySource> = idx
-            .into_iter()
-            .map(|(path, (start, stop))| {
-                let source = body_source.slice(start as usize, stop as usize);
-                (path, source)
-            })
-            .collect();
-        Ok(BundleDirectory {
-            source_map: Arc::new(source_map),
-        })
-    }
-}
-
-impl ReadOnlyDirectory for BundleDirectory {
-    fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError> {
-        self.source_map
-            .get(path)
-            .cloned()
-            .ok_or_else(|| OpenReadError::FileDoesNotExist(path.to_path_buf()))
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.source_map.contains_key(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        let source = self
-            .source_map
-            .get(path)
-            .ok_or_else(|| OpenReadError::FileDoesNotExist(path.to_path_buf()))?;
-        Ok(source.as_slice().to_vec())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::BundleDirectory;
-    use crate::directory::{RAMDirectory, ReadOnlyDirectory, TerminatingWrite};
-    use crate::Directory;
-    use std::io::Write;
-    use std::path::Path;
-
-    #[test]
-    fn test_bundle_directory() {
-        let mut ram_directory = RAMDirectory::default();
-        let test_path_atomic = Path::new("testpath_atomic");
-        let test_path_wrt = Path::new("testpath_wrt");
-        assert!(ram_directory
-            .atomic_write(test_path_atomic, b"titi")
-            .is_ok());
-        {
-            let mut test_wrt = ram_directory.open_write(test_path_wrt).unwrap();
-            assert!(test_wrt.write_all(b"toto").is_ok());
-            assert!(test_wrt.terminate().is_ok());
-        }
-        let mut dest_directory = RAMDirectory::default();
-        let bundle_path = Path::new("bundle");
-        let mut wrt = dest_directory.open_write(bundle_path).unwrap();
-        assert!(ram_directory.serialize_bundle(&mut wrt).is_ok());
-        assert!(wrt.terminate().is_ok());
-        let source = dest_directory.open_read(bundle_path).unwrap();
-        let bundle_directory = BundleDirectory::from_source(source).unwrap();
-        assert_eq!(
-            &bundle_directory.atomic_read(test_path_atomic).unwrap()[..],
-            b"titi"
-        );
-        assert_eq!(
-            &bundle_directory.open_read(test_path_wrt).unwrap()[..],
-            b"toto"
-        );
-    }
-}

src/directory/directory.rs

@@ -100,30 +100,6 @@ fn retry_policy(is_blocking: bool) -> RetryPolicy {
     }
 }
 
-pub trait ReadOnlyDirectory {
-    /// Opens a virtual file for read.
-    ///
-    /// Once a virtual file is open, its data may not
-    /// change.
-    ///
-    /// Specifically, subsequent writes or flushes should
-    /// have no effect on the returned `ReadOnlySource` object.
-    ///
-    /// You should only use this to read files create with [Directory::open_write].
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError>;
-
-    /// Returns true iff the file exists
-    fn exists(&self, path: &Path) -> bool;
-
-    /// Reads the full content file that has been written using
-    /// atomic_write.
-    ///
-    /// This should only be used for small files.
-    ///
-    /// You should only use this to read files create with [Directory::atomic_write].
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>;
-}
-
 /// Write-once read many (WORM) abstraction for where
 /// tantivy's data should be stored.
 ///
@@ -134,9 +110,18 @@ pub trait ReadOnlyDirectory {
 /// - The [`RAMDirectory`](struct.RAMDirectory.html), which
 /// should be used mostly for tests.
 ///
-pub trait Directory:
-    DirectoryClone + ReadOnlyDirectory + fmt::Debug + Send + Sync + 'static
-{
+pub trait Directory: DirectoryClone + fmt::Debug + Send + Sync + 'static {
+    /// Opens a virtual file for read.
+    ///
+    /// Once a virtual file is open, its data may not
+    /// change.
+    ///
+    /// Specifically, subsequent writes or flushes should
+    /// have no effect on the returned `ReadOnlySource` object.
+    ///
+    /// You should only use this to read files create with [`open_write`]
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError>;
+
     /// Removes a file
     ///
     /// Removing a file will not affect an eventual
@@ -146,6 +131,9 @@ pub trait Directory:
     /// `DeleteError::DoesNotExist`.
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError>;
 
+    /// Returns true iff the file exists
+    fn exists(&self, path: &Path) -> bool;
+
     /// Opens a writer for the *virtual file* associated with
     /// a Path.
     ///
@@ -167,6 +155,14 @@ pub trait Directory:
     /// The file may not previously exist.
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError>;
 
+    /// Reads the full content file that has been written using
+    /// atomic_write.
+    ///
+    /// This should only be used for small files.
+    ///
+    /// You should only use this to read files create with [`atomic_write`]
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>;
+
     /// Atomically replace the content of a file with data.
     ///
     /// This calls ensure that reads can never *observe*
@@ -201,7 +197,7 @@ pub trait Directory:
     /// Registers a callback that will be called whenever a change on the `meta.json`
     /// using the `atomic_write` API is detected.
     ///
-    /// The behavior when using `.watch()` on a file using [Directory::open_write] is, on the other
+    /// The behavior when using `.watch()` on a file using `.open_write(...)` is, on the other
     /// hand, undefined.
     ///
     /// The file will be watched for the lifetime of the returned `WatchHandle`. The caller is

src/directory/error.rs

@@ -1,4 +1,4 @@
-use crate::Version;
+use crate::directory::footer::Footer;
 use std::error::Error as StdError;
 use std::fmt;
 use std::io;
@@ -157,65 +157,6 @@ impl StdError for OpenWriteError {
     }
 }
 
-/// Type of index incompatibility between the library and the index found on disk
-/// Used to catch and provide a hint to solve this incompatibility issue
-pub enum Incompatibility {
-    /// This library cannot decompress the index found on disk
-    CompressionMismatch {
-        /// Compression algorithm used by the current version of tantivy
-        library_compression_format: String,
-        /// Compression algorithm that was used to serialise the index
-        index_compression_format: String,
-    },
-    /// The index format found on disk isn't supported by this version of the library
-    IndexMismatch {
-        /// Version used by the library
-        library_version: Version,
-        /// Version the index was built with
-        index_version: Version,
-    },
-}
-
-impl fmt::Debug for Incompatibility {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        match self {
-            Incompatibility::CompressionMismatch {
-                library_compression_format,
-                index_compression_format,
-            } => {
-                let err = format!(
-                    "Library was compiled with {:?} compression, index was compressed with {:?}",
-                    library_compression_format, index_compression_format
-                );
-                let advice = format!(
-                    "Change the feature flag to {:?} and rebuild the library",
-                    index_compression_format
-                );
-                write!(f, "{}. {}", err, advice)?;
-            }
-            Incompatibility::IndexMismatch {
-                library_version,
-                index_version,
-            } => {
-                let err = format!(
-                    "Library version: {}, index version: {}",
-                    library_version.index_format_version, index_version.index_format_version
-                );
-                // TODO make a more useful error message
-                // include the version range that supports this index_format_version
-                let advice = format!(
-                    "Change tantivy to a version compatible with index format {} (e.g. {}.{}.x) \
-                     and rebuild your project.",
-                    index_version.index_format_version, index_version.major, index_version.minor
-                );
-                write!(f, "{}. {}", err, advice)?;
-            }
-        }
-
-        Ok(())
-    }
-}
-
 /// Error that may occur when accessing a file read
 #[derive(Debug)]
 pub enum OpenReadError {
@@ -224,8 +165,8 @@ pub enum OpenReadError {
     /// Any kind of IO error that happens when
     /// interacting with the underlying IO device.
     IOError(IOError),
-    /// This library doesn't support the index version found on disk
-    IncompatibleIndex(Incompatibility),
+    /// The version of tantivy trying to read the index doesn't support its format
+    IncompatibleIndex(Footer),
 }
 
 impl From<IOError> for OpenReadError {
@@ -252,6 +193,20 @@ impl fmt::Display for OpenReadError {
     }
 }
 
+impl StdError for OpenReadError {
+    fn description(&self) -> &str {
+        "error occurred while opening a file for reading"
+    }
+
+    fn cause(&self) -> Option<&dyn StdError> {
+        match *self {
+            OpenReadError::FileDoesNotExist(_) => None,
+            OpenReadError::IOError(ref err) => Some(err),
+            OpenReadError::IncompatibleIndex(_) => None,
+        }
+    }
+}
+
 /// Error that may occur when trying to delete a file
 #[derive(Debug)]
 pub enum DeleteError {
@@ -268,12 +223,6 @@ impl From<IOError> for DeleteError {
     }
 }
 
-impl From<Incompatibility> for OpenReadError {
-    fn from(incompatibility: Incompatibility) -> Self {
-        OpenReadError::IncompatibleIndex(incompatibility)
-    }
-}
-
 impl fmt::Display for DeleteError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {

src/directory/footer.rs

@@ -1,5 +1,4 @@
 use crate::common::{BinarySerializable, CountingWriter, FixedSize, VInt};
-use crate::directory::error::Incompatibility;
 use crate::directory::read_only_source::ReadOnlySource;
 use crate::directory::{AntiCallToken, TerminatingWrite};
 use crate::Version;
@@ -18,11 +17,11 @@ pub struct Footer {
 }
 
 /// Serialises the footer to a byte-array
-/// - versioned_footer_len : 4 bytes
+/// - versioned_footer_len : 4bytes
 ///-  versioned_footer: variable bytes
 /// - meta_len: 4 bytes
 /// - meta: variable bytes
-/// - version_len: 4 bytes
+/// - version_len: 4bytes
 /// - version json: variable bytes
 impl BinarySerializable for Footer {
     fn serialize<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
@@ -87,25 +86,16 @@ impl Footer {
 
     /// Confirms that the index will be read correctly by this version of tantivy
     /// Has to be called after `extract_footer` to make sure it's not accessing uninitialised memory
-    pub fn is_compatible(&self) -> Result<(), Incompatibility> {
-        let library_version = crate::version();
+    pub fn is_compatible(&self) -> bool {
+        let version = &*crate::VERSION;
         match &self.versioned_footer {
             VersionedFooter::V1 {
-                crc32: _crc,
-                store_compression: compression,
+                crc32: _,
+                compression,
             } => {
-                if &library_version.store_compression != compression {
-                    return Err(Incompatibility::CompressionMismatch {
-                        library_compression_format: library_version.store_compression.to_string(),
-                        index_compression_format: compression.to_string(),
-                    });
-                }
-                Ok(())
+                return compression == &version.store_compression;
             }
-            VersionedFooter::UnknownVersion => Err(Incompatibility::IndexMismatch {
-                library_version: library_version.clone(),
-                index_version: self.version.clone(),
-            }),
+            VersionedFooter::UnknownVersion { version: _ } => false,
         }
     }
 }
@@ -113,32 +103,31 @@ impl Footer {
 /// Footer that includes a crc32 hash that enables us to checksum files in the index
 #[derive(Debug, Clone, PartialEq)]
 pub enum VersionedFooter {
-    UnknownVersion,
+    UnknownVersion {
+        version: u32,
+    },
     V1 {
         crc32: CrcHashU32,
-        store_compression: String,
+        compression: String,
     },
 }
 
 impl BinarySerializable for VersionedFooter {
     fn serialize<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
         let mut buf = Vec::new();
+        BinarySerializable::serialize(&self.version(), &mut buf)?;
         match self {
-            VersionedFooter::V1 {
-                crc32,
-                store_compression: compression,
-            } => {
+            VersionedFooter::V1 { crc32, compression } => {
                 // Serializes a valid `VersionedFooter` or panics if the version is unknown
                 // [   version    |   crc_hash  | compression_mode ]
-                // [    0..4      |     4..8    |     variable     ]
-                BinarySerializable::serialize(&1u32, &mut buf)?;
+                // [    0..4      |     4..8    |  variable ]
                 BinarySerializable::serialize(crc32, &mut buf)?;
                 BinarySerializable::serialize(compression, &mut buf)?;
             }
-            VersionedFooter::UnknownVersion => {
+            VersionedFooter::UnknownVersion { version: _ } => {
                 return Err(io::Error::new(
                     io::ErrorKind::InvalidInput,
-                    "Cannot serialize an unknown versioned footer ",
+                    "Cannot serialize an unknown versionned footer ",
                 ));
             }
         }
@@ -156,20 +145,30 @@ impl BinarySerializable for VersionedFooter {
         if version == 1 {
             let crc32 = u32::deserialize(&mut cursor)?;
             let compression = String::deserialize(&mut cursor)?;
-            Ok(VersionedFooter::V1 {
-                crc32,
-                store_compression: compression,
-            })
+            Ok(VersionedFooter::V1 { crc32, compression })
         } else {
-            Ok(VersionedFooter::UnknownVersion)
+            Ok(VersionedFooter::UnknownVersion { version })
         }
     }
 }
 
 impl VersionedFooter {
+    pub fn version(&self) -> u32 {
+        match self {
+            VersionedFooter::V1 {
+                crc32: _,
+                compression: _,
+            } => 1u32,
+            VersionedFooter::UnknownVersion { version, .. } => *version,
+        }
+    }
+
     pub fn crc(&self) -> Option<CrcHashU32> {
         match self {
-            VersionedFooter::V1 { crc32, .. } => Some(*crc32),
+            VersionedFooter::V1 {
+                crc32,
+                compression: _,
+            } => Some(*crc32),
             VersionedFooter::UnknownVersion { .. } => None,
         }
     }
@@ -208,7 +207,7 @@ impl<W: TerminatingWrite> TerminatingWrite for FooterProxy<W> {
         let crc32 = self.hasher.take().unwrap().finalize();
         let footer = Footer::new(VersionedFooter::V1 {
             crc32,
-            store_compression: crate::store::COMPRESSION.to_string(),
+            compression: crate::store::COMPRESSION.to_string(),
         });
         let mut writer = self.writer.take().unwrap();
         footer.append_footer(&mut writer)?;
@@ -228,21 +227,16 @@ mod tests {
     use regex::Regex;
 
     #[test]
-    fn test_versioned_footer() {
+    fn test_footer_version() {
         let mut vec = Vec::new();
         let footer_proxy = FooterProxy::new(&mut vec);
         assert!(footer_proxy.terminate().is_ok());
         assert_eq!(vec.len(), 167);
         let footer = Footer::deserialize(&mut &vec[..]).unwrap();
-        if let VersionedFooter::V1 {
-            crc32: _,
-            store_compression,
-        } = footer.versioned_footer
-        {
-            assert_eq!(store_compression, crate::store::COMPRESSION);
-        } else {
-            panic!("Versioned footer should be V1.");
-        }
+        assert_eq!(
+            footer.versioned_footer.version(),
+            crate::INDEX_FORMAT_VERSION
+        );
         assert_eq!(&footer.version, crate::version());
     }
 
@@ -252,7 +246,7 @@ mod tests {
         let crc32 = 123456u32;
         let footer: Footer = Footer::new(VersionedFooter::V1 {
             crc32,
-            store_compression: "lz4".to_string(),
+            compression: "lz4".to_string(),
         });
         footer.serialize(&mut buffer).unwrap();
         let footer_deser = Footer::deserialize(&mut &buffer[..]).unwrap();
@@ -261,10 +255,11 @@ mod tests {
 
     #[test]
     fn footer_length() {
+        // test to make sure the ascii art in the doc-strings is correct
         let crc32 = 1111111u32;
         let versioned_footer = VersionedFooter::V1 {
             crc32,
-            store_compression: "lz4".to_string(),
+            compression: "lz4".to_string(),
         };
         let mut buf = Vec::new();
         versioned_footer.serialize(&mut buf).unwrap();
@@ -304,7 +299,7 @@ mod tests {
         let expected_crc: u32 = LittleEndian::read_u32(&v_footer_bytes[5..9]) as CrcHashU32;
         let expected_versioned_footer: VersionedFooter = VersionedFooter::V1 {
             crc32: expected_crc,
-            store_compression: "lz4".to_string(),
+            compression: "lz4".to_string(),
         };
         assert_eq!(versioned_footer, expected_versioned_footer);
         let mut buffer = Vec::new();
@@ -318,22 +313,11 @@ mod tests {
         let mut b = &v_footer_bytes[..];
         let versioned_footer = VersionedFooter::deserialize(&mut b).unwrap();
         assert!(b.is_empty());
-        let expected_versioned_footer = VersionedFooter::UnknownVersion;
+        let expected_versioned_footer = VersionedFooter::UnknownVersion {
+            version: 16_777_219u32,
+        };
         assert_eq!(versioned_footer, expected_versioned_footer);
         let mut buf = Vec::new();
         assert!(versioned_footer.serialize(&mut buf).is_err());
     }
-
-    #[test]
-    #[cfg(not(feature = "lz4"))]
-    fn compression_mismatch() {
-        let crc32 = 1111111u32;
-        let versioned_footer = VersionedFooter::V1 {
-            crc32,
-            store_compression: "lz4".to_string(),
-        };
-        let footer = Footer::new(versioned_footer);
-        let res = footer.is_compatible();
-        assert!(res.is_err());
-    }
 }

src/directory/managed_directory.rs

@@ -9,8 +9,8 @@ use crate::directory::{ReadOnlySource, WritePtr};
 use crate::directory::{WatchCallback, WatchHandle};
 use crate::error::DataCorruption;
 use crate::Directory;
+use crate::Result;
 
-use crate::directory::directory::ReadOnlyDirectory;
 use crc32fast::Hasher;
 use serde_json;
 use std::collections::HashSet;
@@ -66,7 +66,7 @@ fn save_managed_paths(
 
 impl ManagedDirectory {
     /// Wraps a directory as managed directory.
-    pub fn wrap<Dir: Directory>(directory: Dir) -> crate::Result<ManagedDirectory> {
+    pub fn wrap<Dir: Directory>(directory: Dir) -> Result<ManagedDirectory> {
         match directory.atomic_read(&MANAGED_FILEPATH) {
             Ok(data) => {
                 let managed_files_json = String::from_utf8_lossy(&data);
@@ -89,10 +89,8 @@ impl ManagedDirectory {
                 meta_informations: Arc::default(),
             }),
             Err(OpenReadError::IOError(e)) => Err(From::from(e)),
-            Err(OpenReadError::IncompatibleIndex(incompatibility)) => {
-                // For the moment, this should never happen  `meta.json`
-                // do not have any footer and cannot detect incompatibility.
-                Err(crate::TantivyError::IncompatibleIndex(incompatibility))
+            Err(OpenReadError::IncompatibleIndex(footer)) => {
+                Err(crate::Error::IncompatibleIndex(format!("{:?}", footer)))
             }
         }
     }
@@ -265,6 +263,16 @@ impl ManagedDirectory {
 }
 
 impl Directory for ManagedDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        let read_only_source = self.directory.open_read(path)?;
+        let (footer, reader) = Footer::extract_footer(read_only_source)
+            .map_err(|err| IOError::with_path(path.to_path_buf(), err))?;
+        if !footer.is_compatible() {
+            return Err(OpenReadError::IncompatibleIndex(footer));
+        }
+        Ok(reader)
+    }
+
     fn open_write(&mut self, path: &Path) -> result::Result<WritePtr, OpenWriteError> {
         self.register_file_as_managed(path)
             .map_err(|e| IOError::with_path(path.to_owned(), e))?;
@@ -282,10 +290,18 @@ impl Directory for ManagedDirectory {
         self.directory.atomic_write(path, data)
     }
 
+    fn atomic_read(&self, path: &Path) -> result::Result<Vec<u8>, OpenReadError> {
+        self.directory.atomic_read(path)
+    }
+
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
         self.directory.delete(path)
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        self.directory.exists(path)
+    }
+
     fn acquire_lock(&self, lock: &Lock) -> result::Result<DirectoryLock, LockError> {
         self.directory.acquire_lock(lock)
     }
@@ -295,24 +311,6 @@ impl Directory for ManagedDirectory {
     }
 }
 
-impl ReadOnlyDirectory for ManagedDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        let read_only_source = self.directory.open_read(path)?;
-        let (footer, reader) = Footer::extract_footer(read_only_source)
-            .map_err(|err| IOError::with_path(path.to_path_buf(), err))?;
-        footer.is_compatible()?;
-        Ok(reader)
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.directory.exists(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> result::Result<Vec<u8>, OpenReadError> {
-        self.directory.atomic_read(path)
-    }
-}
-
 impl Clone for ManagedDirectory {
     fn clone(&self) -> ManagedDirectory {
         ManagedDirectory {
@@ -326,9 +324,7 @@ impl Clone for ManagedDirectory {
 #[cfg(test)]
 mod tests_mmap_specific {
 
-    use crate::directory::{
-        Directory, ManagedDirectory, MmapDirectory, ReadOnlyDirectory, TerminatingWrite,
-    };
+    use crate::directory::{Directory, ManagedDirectory, MmapDirectory, TerminatingWrite};
     use std::collections::HashSet;
     use std::fs::OpenOptions;
     use std::io::Write;

src/directory/mmap_directory.rs

@@ -6,7 +6,6 @@ use self::notify::RawEvent;
 use self::notify::RecursiveMode;
 use self::notify::Watcher;
 use crate::core::META_FILEPATH;
-use crate::directory::directory::ReadOnlyDirectory;
 use crate::directory::error::LockError;
 use crate::directory::error::{
     DeleteError, IOError, OpenDirectoryError, OpenReadError, OpenWriteError,
@@ -132,13 +131,14 @@ impl MmapCache {
         }
         self.cache.remove(full_path);
         self.counters.miss += 1;
-        let mmap_opt = open_mmap(full_path)?;
-        Ok(mmap_opt.map(|mmap| {
+        Ok(if let Some(mmap) = open_mmap(full_path)? {
             let mmap_arc: Arc<BoxedData> = Arc::new(Box::new(mmap));
             let mmap_weak = Arc::downgrade(&mmap_arc);
             self.cache.insert(full_path.to_owned(), mmap_weak);
-            mmap_arc
-        }))
+            Some(mmap_arc)
+        } else {
+            None
+        })
     }
 }
 
@@ -408,6 +408,24 @@ impl TerminatingWrite for SafeFileWriter {
 }
 
 impl Directory for MmapDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        debug!("Open Read {:?}", path);
+        let full_path = self.resolve_path(path);
+
+        let mut mmap_cache = self.inner.mmap_cache.write().map_err(|_| {
+            let msg = format!(
+                "Failed to acquired write lock \
+                 on mmap cache while reading {:?}",
+                path
+            );
+            IOError::with_path(path.to_owned(), make_io_err(msg))
+        })?;
+        Ok(mmap_cache
+            .get_mmap(&full_path)?
+            .map(ReadOnlySource::from)
+            .unwrap_or_else(ReadOnlySource::empty))
+    }
+
     /// Any entry associated to the path in the mmap will be
     /// removed before the file is deleted.
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
@@ -426,6 +444,11 @@ impl Directory for MmapDirectory {
         }
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        let full_path = self.resolve_path(path);
+        full_path.exists()
+    }
+
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError> {
         debug!("Open Write {:?}", path);
         let full_path = self.resolve_path(path);
@@ -456,6 +479,25 @@ impl Directory for MmapDirectory {
         Ok(BufWriter::new(Box::new(writer)))
     }
 
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
+        let full_path = self.resolve_path(path);
+        let mut buffer = Vec::new();
+        match File::open(&full_path) {
+            Ok(mut file) => {
+                file.read_to_end(&mut buffer)
+                    .map_err(|e| IOError::with_path(path.to_owned(), e))?;
+                Ok(buffer)
+            }
+            Err(e) => {
+                if e.kind() == io::ErrorKind::NotFound {
+                    Err(OpenReadError::FileDoesNotExist(path.to_owned()))
+                } else {
+                    Err(IOError::with_path(path.to_owned(), e).into())
+                }
+            }
+        }
+    }
+
     fn atomic_write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
         debug!("Atomic Write {:?}", path);
         let full_path = self.resolve_path(path);
@@ -489,50 +531,6 @@ impl Directory for MmapDirectory {
     }
 }
 
-impl ReadOnlyDirectory for MmapDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        debug!("Open Read {:?}", path);
-        let full_path = self.resolve_path(path);
-
-        let mut mmap_cache = self.inner.mmap_cache.write().map_err(|_| {
-            let msg = format!(
-                "Failed to acquired write lock \
-                 on mmap cache while reading {:?}",
-                path
-            );
-            IOError::with_path(path.to_owned(), make_io_err(msg))
-        })?;
-        Ok(mmap_cache
-            .get_mmap(&full_path)?
-            .map(ReadOnlySource::from)
-            .unwrap_or_else(ReadOnlySource::empty))
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        let full_path = self.resolve_path(path);
-        full_path.exists()
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        let full_path = self.resolve_path(path);
-        let mut buffer = Vec::new();
-        match File::open(&full_path) {
-            Ok(mut file) => {
-                file.read_to_end(&mut buffer)
-                    .map_err(|e| IOError::with_path(path.to_owned(), e))?;
-                Ok(buffer)
-            }
-            Err(e) => {
-                if e.kind() == io::ErrorKind::NotFound {
-                    Err(OpenReadError::FileDoesNotExist(path.to_owned()))
-                } else {
-                    Err(IOError::with_path(path.to_owned(), e).into())
-                }
-            }
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
 

src/directory/mod.rs

@@ -7,7 +7,6 @@ WORM directory abstraction.
 #[cfg(feature = "mmap")]
 mod mmap_directory;
 
-mod bundle_directory;
 mod directory;
 mod directory_lock;
 mod footer;
@@ -20,13 +19,15 @@ mod watch_event_router;
 pub mod error;
 
 pub use self::directory::DirectoryLock;
-pub use self::directory::{Directory, DirectoryClone, ReadOnlyDirectory};
+pub use self::directory::{Directory, DirectoryClone};
 pub use self::directory_lock::{Lock, INDEX_WRITER_LOCK, META_LOCK};
 pub use self::ram_directory::RAMDirectory;
 pub use self::read_only_source::ReadOnlySource;
-pub use self::watch_event_router::{WatchCallback, WatchCallbackList, WatchHandle};
+pub(crate) use self::watch_event_router::WatchCallbackList;
+pub use self::watch_event_router::{WatchCallback, WatchHandle};
 use std::io::{self, BufWriter, Write};
 use std::path::PathBuf;
+
 /// Outcome of the Garbage collection
 pub struct GarbageCollectionResult {
     /// List of files that were deleted in this cycle
@@ -47,9 +48,6 @@ pub use self::mmap_directory::MmapDirectory;
 pub use self::managed_directory::ManagedDirectory;
 
 /// Struct used to prevent from calling [`terminate_ref`](trait.TerminatingWrite#method.terminate_ref) directly
-///
-/// The point is that while the type is public, it cannot be built by anyone
-/// outside of this module.
 pub struct AntiCallToken(());
 
 /// Trait used to indicate when no more write need to be done on a writer

src/directory/ram_directory.rs

@@ -1,6 +1,4 @@
-use crate::common::CountingWriter;
 use crate::core::META_FILEPATH;
-use crate::directory::directory::ReadOnlyDirectory;
 use crate::directory::error::{DeleteError, OpenReadError, OpenWriteError};
 use crate::directory::AntiCallToken;
 use crate::directory::WatchCallbackList;
@@ -117,22 +115,6 @@ impl InnerDirectory {
     fn total_mem_usage(&self) -> usize {
         self.fs.values().map(|f| f.len()).sum()
     }
-
-    fn serialize_bundle(&self, wrt: &mut WritePtr) -> io::Result<()> {
-        let mut counting_writer = CountingWriter::wrap(wrt);
-        let mut file_index: HashMap<PathBuf, (u64, u64)> = HashMap::default();
-        for (path, source) in &self.fs {
-            let start = counting_writer.written_bytes();
-            counting_writer.write_all(source.as_slice())?;
-            let stop = counting_writer.written_bytes();
-            file_index.insert(path.to_path_buf(), (start, stop));
-        }
-        let index_offset = counting_writer.written_bytes();
-        serde_json::to_writer(&mut counting_writer, &file_index)?;
-        let index_offset_buffer = index_offset.to_le_bytes();
-        counting_writer.write_all(&index_offset_buffer[..])?;
-        Ok(())
-    }
 }
 
 impl fmt::Debug for RAMDirectory {
@@ -162,18 +144,13 @@ impl RAMDirectory {
     pub fn total_mem_usage(&self) -> usize {
         self.fs.read().unwrap().total_mem_usage()
     }
-
-    /// Serialize the RAMDirectory into a bundle.
-    ///
-    /// This method will fail, write nothing, and return an error if a
-    /// clone of this repository exists.
-    pub fn serialize_bundle(self, wrt: &mut WritePtr) -> io::Result<()> {
-        let inner_directory_rlock = self.fs.read().unwrap();
-        inner_directory_rlock.serialize_bundle(wrt)
-    }
 }
 
 impl Directory for RAMDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        self.fs.read().unwrap().open_read(path)
+    }
+
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
         fail_point!("RAMDirectory::delete", |_| {
             use crate::directory::error::IOError;
@@ -183,6 +160,10 @@ impl Directory for RAMDirectory {
         self.fs.write().unwrap().delete(path)
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        self.fs.read().unwrap().exists(path)
+    }
+
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError> {
         let mut fs = self.fs.write().unwrap();
         let path_buf = PathBuf::from(path);
@@ -196,6 +177,10 @@ impl Directory for RAMDirectory {
         }
     }
 
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
+        Ok(self.open_read(path)?.as_slice().to_owned())
+    }
+
     fn atomic_write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
         fail_point!("RAMDirectory::atomic_write", |msg| Err(io::Error::new(
             io::ErrorKind::Other,
@@ -219,17 +204,3 @@ impl Directory for RAMDirectory {
         Ok(self.fs.write().unwrap().watch(watch_callback))
     }
 }
-
-impl ReadOnlyDirectory for RAMDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        self.fs.read().unwrap().open_read(path)
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.fs.read().unwrap().exists(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        Ok(self.open_read(path)?.as_slice().to_owned())
-    }
-}

src/directory/watch_event_router.rs

@@ -24,20 +24,13 @@ pub struct WatchCallbackList {
 #[derive(Clone)]
 pub struct WatchHandle(Arc<WatchCallback>);
 
-impl WatchHandle {
-    /// Create a WatchHandle handle.
-    pub fn new(watch_callback: Arc<WatchCallback>) -> WatchHandle {
-        WatchHandle(watch_callback)
-    }
-}
-
 impl WatchCallbackList {
     /// Suscribes a new callback and returns a handle that controls the lifetime of the callback.
     pub fn subscribe(&self, watch_callback: WatchCallback) -> WatchHandle {
         let watch_callback_arc = Arc::new(watch_callback);
         let watch_callback_weak = Arc::downgrade(&watch_callback_arc);
         self.router.write().unwrap().push(watch_callback_weak);
-        WatchHandle::new(watch_callback_arc)
+        WatchHandle(watch_callback_arc)
     }
 
     fn list_callback(&self) -> Vec<Arc<WatchCallback>> {

src/error.rs

@@ -2,8 +2,8 @@
 
 use std::io;
 
+use crate::directory::error::LockError;
 use crate::directory::error::{IOError, OpenDirectoryError, OpenReadError, OpenWriteError};
-use crate::directory::error::{Incompatibility, LockError};
 use crate::fastfield::FastFieldNotAvailableError;
 use crate::query;
 use crate::schema;
@@ -25,10 +25,10 @@ impl DataCorruption {
         }
     }
 
-    pub fn comment_only<TS: ToString>(comment: TS) -> DataCorruption {
+    pub fn comment_only(comment: String) -> DataCorruption {
         DataCorruption {
             filepath: None,
-            comment: comment.to_string(),
+            comment,
         }
     }
 }
@@ -81,8 +81,11 @@ pub enum TantivyError {
     #[fail(display = "System error.'{}'", _0)]
     SystemError(String),
     /// Index incompatible with current version of tantivy
-    #[fail(display = "{:?}", _0)]
-    IncompatibleIndex(Incompatibility),
+    #[fail(
+        display = "Current version of tantivy is incompatible with index version: '{}'",
+        _0
+    )]
+    IncompatibleIndex(String),
 }
 
 impl From<DataCorruption> for TantivyError {
@@ -132,8 +135,8 @@ impl From<OpenReadError> for TantivyError {
         match error {
             OpenReadError::FileDoesNotExist(filepath) => TantivyError::PathDoesNotExist(filepath),
             OpenReadError::IOError(io_error) => TantivyError::IOError(io_error),
-            OpenReadError::IncompatibleIndex(incompatibility) => {
-                TantivyError::IncompatibleIndex(incompatibility)
+            OpenReadError::IncompatibleIndex(tantivy_err) => {
+                TantivyError::IncompatibleIndex(format!("{:?}", tantivy_err))
             }
         }
     }

src/fastfield/delete.rs

@@ -1,8 +1,9 @@
-use crate::common::{BitSet, HasLen};
+use crate::common::HasLen;
 use crate::directory::ReadOnlySource;
 use crate::directory::WritePtr;
 use crate::space_usage::ByteCount;
 use crate::DocId;
+use bit_set::BitSet;
 use std::io;
 use std::io::Write;
 
@@ -16,7 +17,7 @@ pub fn write_delete_bitset(
 ) -> io::Result<()> {
     let mut byte = 0u8;
     let mut shift = 0u8;
-    for doc in 0..max_doc {
+    for doc in 0..(max_doc as usize) {
         if delete_bitset.contains(doc) {
             byte |= 1 << shift;
         }
@@ -31,7 +32,7 @@ pub fn write_delete_bitset(
     if max_doc % 8 > 0 {
         writer.write_all(&[byte])?;
     }
-    Ok(())
+    writer.flush()
 }
 
 /// Set of deleted `DocId`s.
@@ -85,6 +86,7 @@ impl HasLen for DeleteBitSet {
 mod tests {
     use super::*;
     use crate::directory::*;
+    use bit_set::BitSet;
     use std::path::PathBuf;
 
     fn test_delete_bitset_helper(bitset: &BitSet, max_doc: u32) {
@@ -93,26 +95,27 @@ mod tests {
         {
             let mut writer = directory.open_write(&*test_path).unwrap();
             write_delete_bitset(bitset, max_doc, &mut writer).unwrap();
-            writer.terminate().unwrap();
         }
-        let source = directory.open_read(&test_path).unwrap();
-        let delete_bitset = DeleteBitSet::open(source);
-        for doc in 0..max_doc {
-            assert_eq!(bitset.contains(doc), delete_bitset.is_deleted(doc as DocId));
+        {
+            let source = directory.open_read(&test_path).unwrap();
+            let delete_bitset = DeleteBitSet::open(source);
+            for doc in 0..max_doc as usize {
+                assert_eq!(bitset.contains(doc), delete_bitset.is_deleted(doc as DocId));
+            }
+            assert_eq!(delete_bitset.len(), bitset.len());
         }
-        assert_eq!(delete_bitset.len(), bitset.len());
     }
 
     #[test]
     fn test_delete_bitset() {
         {
-            let mut bitset = BitSet::with_max_value(10);
+            let mut bitset = BitSet::with_capacity(10);
             bitset.insert(1);
             bitset.insert(9);
             test_delete_bitset_helper(&bitset, 10);
         }
         {
-            let mut bitset = BitSet::with_max_value(8);
+            let mut bitset = BitSet::with_capacity(8);
             bitset.insert(1);
             bitset.insert(2);
             bitset.insert(3);

src/fastfield/mod.rs

@@ -33,7 +33,6 @@ pub use self::reader::FastFieldReader;
 pub use self::readers::FastFieldReaders;
 pub use self::serializer::FastFieldSerializer;
 pub use self::writer::{FastFieldsWriter, IntFastFieldWriter};
-use crate::chrono::{NaiveDateTime, Utc};
 use crate::common;
 use crate::schema::Cardinality;
 use crate::schema::FieldType;
@@ -50,7 +49,7 @@ mod serializer;
 mod writer;
 
 /// Trait for types that are allowed for fast fields: (u64, i64 and f64).
-pub trait FastValue: Clone + Copy + Send + Sync + PartialOrd {
+pub trait FastValue: Default + Clone + Copy + Send + Sync + PartialOrd {
     /// Converts a value from u64
     ///
     /// Internally all fast field values are encoded as u64.
@@ -70,12 +69,6 @@ pub trait FastValue: Clone + Copy + Send + Sync + PartialOrd {
     /// Cast value to `u64`.
     /// The value is just reinterpreted in memory.
     fn as_u64(&self) -> u64;
-
-    /// Build a default value. This default value is never used, so the value does not
-    /// really matter.
-    fn make_zero() -> Self {
-        Self::from_u64(0i64.to_u64())
-    }
 }
 
 impl FastValue for u64 {
@@ -142,34 +135,11 @@ impl FastValue for f64 {
     }
 }
 
-impl FastValue for crate::DateTime {
-    fn from_u64(timestamp_u64: u64) -> Self {
-        let timestamp_i64 = i64::from_u64(timestamp_u64);
-        crate::DateTime::from_utc(NaiveDateTime::from_timestamp(timestamp_i64, 0), Utc)
-    }
-
-    fn to_u64(&self) -> u64 {
-        self.timestamp().to_u64()
-    }
-
-    fn fast_field_cardinality(field_type: &FieldType) -> Option<Cardinality> {
-        match *field_type {
-            FieldType::Date(ref integer_options) => integer_options.get_fastfield_cardinality(),
-            _ => None,
-        }
-    }
-
-    fn as_u64(&self) -> u64 {
-        self.timestamp().as_u64()
-    }
-}
-
 fn value_to_u64(value: &Value) -> u64 {
     match *value {
         Value::U64(ref val) => *val,
         Value::I64(ref val) => common::i64_to_u64(*val),
         Value::F64(ref val) => common::f64_to_u64(*val),
-        Value::Date(ref datetime) => common::i64_to_u64(datetime.timestamp()),
         _ => panic!("Expected a u64/i64/f64 field, got {:?} ", value),
     }
 }
@@ -179,14 +149,12 @@ mod tests {
 
     use super::*;
     use crate::common::CompositeFile;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+    use crate::directory::{Directory, RAMDirectory, WritePtr};
     use crate::fastfield::FastFieldReader;
-    use crate::merge_policy::NoMergePolicy;
+    use crate::schema::Document;
     use crate::schema::Field;
     use crate::schema::Schema;
     use crate::schema::FAST;
-    use crate::schema::{Document, IntOptions};
-    use crate::{Index, SegmentId, SegmentReader};
     use once_cell::sync::Lazy;
     use rand::prelude::SliceRandom;
     use rand::rngs::StdRng;
@@ -210,12 +178,6 @@ mod tests {
         assert_eq!(test_fastfield.get(2), 300);
     }
 
-    #[test]
-    pub fn test_fastfield_i64_u64() {
-        let datetime = crate::DateTime::from_utc(NaiveDateTime::from_timestamp(0i64, 0), Utc);
-        assert_eq!(i64::from_u64(datetime.to_u64()), 0i64);
-    }
-
     #[test]
     fn test_intfastfield_small() {
         let path = Path::new("test");
@@ -467,93 +429,6 @@ mod tests {
             }
         }
     }
-
-    #[test]
-    fn test_merge_missing_date_fast_field() {
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", FAST);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-        index_writer.add_document(doc!(date_field =>crate::chrono::prelude::Utc::now()));
-        index_writer.commit().unwrap();
-        index_writer.add_document(doc!());
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let segment_ids: Vec<SegmentId> = reader
-            .searcher()
-            .segment_readers()
-            .iter()
-            .map(SegmentReader::segment_id)
-            .collect();
-        assert_eq!(segment_ids.len(), 2);
-        let merge_future = index_writer.merge(&segment_ids[..]);
-        let merge_res = futures::executor::block_on(merge_future);
-        assert!(merge_res.is_ok());
-        assert!(reader.reload().is_ok());
-        assert_eq!(reader.searcher().segment_readers().len(), 1);
-    }
-
-    #[test]
-    fn test_default_datetime() {
-        assert_eq!(crate::DateTime::make_zero().timestamp(), 0i64);
-    }
-
-    #[test]
-    fn test_datefastfield() {
-        use crate::fastfield::FastValue;
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", FAST);
-        let multi_date_field = schema_builder.add_date_field(
-            "multi_date",
-            IntOptions::default().set_fast(Cardinality::MultiValues),
-        );
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-        index_writer.add_document(doc!(
-            date_field => crate::DateTime::from_u64(1i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(2i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(3i64.to_u64())
-        ));
-        index_writer.add_document(doc!(
-            date_field => crate::DateTime::from_u64(4i64.to_u64())
-        ));
-        index_writer.add_document(doc!(
-            multi_date_field => crate::DateTime::from_u64(5i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(6i64.to_u64())
-        ));
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let searcher = reader.searcher();
-        assert_eq!(searcher.segment_readers().len(), 1);
-        let segment_reader = searcher.segment_reader(0);
-        let fast_fields = segment_reader.fast_fields();
-        let date_fast_field = fast_fields.date(date_field).unwrap();
-        let dates_fast_field = fast_fields.dates(multi_date_field).unwrap();
-        let mut dates = vec![];
-        {
-            assert_eq!(date_fast_field.get(0u32).timestamp(), 1i64);
-            dates_fast_field.get_vals(0u32, &mut dates);
-            assert_eq!(dates.len(), 2);
-            assert_eq!(dates[0].timestamp(), 2i64);
-            assert_eq!(dates[1].timestamp(), 3i64);
-        }
-        {
-            assert_eq!(date_fast_field.get(1u32).timestamp(), 4i64);
-            dates_fast_field.get_vals(1u32, &mut dates);
-            assert!(dates.is_empty());
-        }
-        {
-            assert_eq!(date_fast_field.get(2u32).timestamp(), 0i64);
-            dates_fast_field.get_vals(2u32, &mut dates);
-            assert_eq!(dates.len(), 2);
-            assert_eq!(dates[0].timestamp(), 5i64);
-            assert_eq!(dates[1].timestamp(), 6i64);
-        }
-    }
 }
 
 #[cfg(all(test, feature = "unstable"))]

src/fastfield/multivalued/reader.rs

@@ -45,7 +45,7 @@ impl<Item: FastValue> MultiValueIntFastFieldReader<Item> {
     pub fn get_vals(&self, doc: DocId, vals: &mut Vec<Item>) {
         let (start, stop) = self.range(doc);
         let len = (stop - start) as usize;
-        vals.resize(len, Item::make_zero());
+        vals.resize(len, Item::default());
         self.vals_reader.get_range_u64(start, &mut vals[..]);
     }
 

src/fastfield/reader.rs

@@ -4,7 +4,7 @@ use crate::common::compute_num_bits;
 use crate::common::BinarySerializable;
 use crate::common::CompositeFile;
 use crate::directory::ReadOnlySource;
-use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+use crate::directory::{Directory, RAMDirectory, WritePtr};
 use crate::fastfield::{FastFieldSerializer, FastFieldsWriter};
 use crate::schema::Schema;
 use crate::schema::FAST;

src/fastfield/readers.rs

@@ -15,11 +15,9 @@ pub struct FastFieldReaders {
     fast_field_i64: HashMap<Field, FastFieldReader<i64>>,
     fast_field_u64: HashMap<Field, FastFieldReader<u64>>,
     fast_field_f64: HashMap<Field, FastFieldReader<f64>>,
-    fast_field_date: HashMap<Field, FastFieldReader<crate::DateTime>>,
     fast_field_i64s: HashMap<Field, MultiValueIntFastFieldReader<i64>>,
     fast_field_u64s: HashMap<Field, MultiValueIntFastFieldReader<u64>>,
     fast_field_f64s: HashMap<Field, MultiValueIntFastFieldReader<f64>>,
-    fast_field_dates: HashMap<Field, MultiValueIntFastFieldReader<crate::DateTime>>,
     fast_bytes: HashMap<Field, BytesFastFieldReader>,
     fast_fields_composite: CompositeFile,
 }
@@ -28,7 +26,6 @@ enum FastType {
     I64,
     U64,
     F64,
-    Date,
 }
 
 fn type_and_cardinality(field_type: &FieldType) -> Option<(FastType, Cardinality)> {
@@ -42,9 +39,6 @@ fn type_and_cardinality(field_type: &FieldType) -> Option<(FastType, Cardinality
         FieldType::F64(options) => options
             .get_fastfield_cardinality()
             .map(|cardinality| (FastType::F64, cardinality)),
-        FieldType::Date(options) => options
-            .get_fastfield_cardinality()
-            .map(|cardinality| (FastType::Date, cardinality)),
         FieldType::HierarchicalFacet => Some((FastType::U64, Cardinality::MultiValues)),
         _ => None,
     }
@@ -59,11 +53,9 @@ impl FastFieldReaders {
             fast_field_i64: Default::default(),
             fast_field_u64: Default::default(),
             fast_field_f64: Default::default(),
-            fast_field_date: Default::default(),
             fast_field_i64s: Default::default(),
             fast_field_u64s: Default::default(),
             fast_field_f64s: Default::default(),
-            fast_field_dates: Default::default(),
             fast_bytes: Default::default(),
             fast_fields_composite: fast_fields_composite.clone(),
         };
@@ -103,12 +95,6 @@ impl FastFieldReaders {
                                         FastFieldReader::open(fast_field_data.clone()),
                                     );
                                 }
-                                FastType::Date => {
-                                    fast_field_readers.fast_field_date.insert(
-                                        field,
-                                        FastFieldReader::open(fast_field_data.clone()),
-                                    );
-                                }
                             }
                         } else {
                             return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
@@ -144,14 +130,6 @@ impl FastFieldReaders {
                                         .fast_field_f64s
                                         .insert(field, multivalued_int_fast_field);
                                 }
-                                FastType::Date => {
-                                    let vals_reader = FastFieldReader::open(fast_field_data);
-                                    let multivalued_int_fast_field =
-                                        MultiValueIntFastFieldReader::open(idx_reader, vals_reader);
-                                    fast_field_readers
-                                        .fast_field_dates
-                                        .insert(field, multivalued_int_fast_field);
-                                }
                             }
                         } else {
                             return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
@@ -178,6 +156,8 @@ impl FastFieldReaders {
     /// If the field is a i64-fast field, return the associated u64 reader. Values are
     /// mapped from i64 to u64 using a (well the, it is unique) monotonic mapping.    ///
     ///
+    ///TODO should it also be lenient with f64?
+    ///
     /// This method is useful when merging segment reader.
     pub(crate) fn u64_lenient(&self, field: Field) -> Option<FastFieldReader<u64>> {
         if let Some(u64_ff_reader) = self.u64(field) {
@@ -186,12 +166,6 @@ impl FastFieldReaders {
         if let Some(i64_ff_reader) = self.i64(field) {
             return Some(i64_ff_reader.into_u64_reader());
         }
-        if let Some(f64_ff_reader) = self.f64(field) {
-            return Some(f64_ff_reader.into_u64_reader());
-        }
-        if let Some(date_ff_reader) = self.date(field) {
-            return Some(date_ff_reader.into_u64_reader());
-        }
         None
     }
 
@@ -202,13 +176,6 @@ impl FastFieldReaders {
         self.fast_field_i64.get(&field).cloned()
     }
 
-    /// Returns the `i64` fast field reader reader associated to `field`.
-    ///
-    /// If `field` is not a i64 fast field, this method returns `None`.
-    pub fn date(&self, field: Field) -> Option<FastFieldReader<crate::DateTime>> {
-        self.fast_field_date.get(&field).cloned()
-    }
-
     /// Returns the `f64` fast field reader reader associated to `field`.
     ///
     /// If `field` is not a f64 fast field, this method returns `None`.
@@ -235,9 +202,6 @@ impl FastFieldReaders {
         if let Some(i64s_ff_reader) = self.i64s(field) {
             return Some(i64s_ff_reader.into_u64s_reader());
         }
-        if let Some(f64s_ff_reader) = self.f64s(field) {
-            return Some(f64s_ff_reader.into_u64s_reader());
-        }
         None
     }
 
@@ -255,13 +219,6 @@ impl FastFieldReaders {
         self.fast_field_f64s.get(&field).cloned()
     }
 
-    /// Returns a `crate::DateTime` multi-valued fast field reader reader associated to `field`.
-    ///
-    /// If `field` is not a `crate::DateTime` multi-valued fast field, this method returns `None`.
-    pub fn dates(&self, field: Field) -> Option<MultiValueIntFastFieldReader<crate::DateTime>> {
-        self.fast_field_dates.get(&field).cloned()
-    }
-
     /// Returns the `bytes` fast field reader associated to `field`.
     ///
     /// If `field` is not a bytes fast field, returns `None`.

src/fastfield/writer.rs

@@ -4,7 +4,7 @@ use crate::common::BinarySerializable;
 use crate::common::VInt;
 use crate::fastfield::{BytesFastFieldWriter, FastFieldSerializer};
 use crate::postings::UnorderedTermId;
-use crate::schema::{Cardinality, Document, Field, FieldEntry, FieldType, Schema};
+use crate::schema::{Cardinality, Document, Field, FieldType, Schema};
 use crate::termdict::TermOrdinal;
 use fnv::FnvHashMap;
 use std::collections::HashMap;
@@ -17,14 +17,6 @@ pub struct FastFieldsWriter {
     bytes_value_writers: Vec<BytesFastFieldWriter>,
 }
 
-fn fast_field_default_value(field_entry: &FieldEntry) -> u64 {
-    match *field_entry.field_type() {
-        FieldType::I64(_) | FieldType::Date(_) => common::i64_to_u64(0i64),
-        FieldType::F64(_) => common::f64_to_u64(0.0f64),
-        _ => 0u64,
-    }
-}
-
 impl FastFieldsWriter {
     /// Create all `FastFieldWriter` required by the schema.
     pub fn from_schema(schema: &Schema) -> FastFieldsWriter {
@@ -33,15 +25,18 @@ impl FastFieldsWriter {
         let mut bytes_value_writers = Vec::new();
 
         for (field, field_entry) in schema.fields() {
+            let default_value = match *field_entry.field_type() {
+                FieldType::I64(_) => common::i64_to_u64(0i64),
+                FieldType::F64(_) => common::f64_to_u64(0.0f64),
+                _ => 0u64,
+            };
             match *field_entry.field_type() {
                 FieldType::I64(ref int_options)
                 | FieldType::U64(ref int_options)
-                | FieldType::F64(ref int_options)
-                | FieldType::Date(ref int_options) => {
+                | FieldType::F64(ref int_options) => {
                     match int_options.get_fastfield_cardinality() {
                         Some(Cardinality::SingleValue) => {
                             let mut fast_field_writer = IntFastFieldWriter::new(field);
-                            let default_value = fast_field_default_value(field_entry);
                             fast_field_writer.set_val_if_missing(default_value);
                             single_value_writers.push(fast_field_writer);
                         }

src/indexer/index_writer.rs

@@ -1,7 +1,6 @@
 use super::operation::{AddOperation, UserOperation};
 use super::segment_updater::SegmentUpdater;
 use super::PreparedCommit;
-use crate::common::BitSet;
 use crate::core::Index;
 use crate::core::Segment;
 use crate::core::SegmentComponent;
@@ -24,6 +23,7 @@ use crate::schema::Document;
 use crate::schema::IndexRecordOption;
 use crate::schema::Term;
 use crate::Opstamp;
+use bit_set::BitSet;
 use crossbeam::channel;
 use futures::executor::block_on;
 use futures::future::Future;
@@ -115,7 +115,7 @@ fn compute_deleted_bitset(
             while docset.advance() {
                 let deleted_doc = docset.doc();
                 if deleted_doc < limit_doc {
-                    delete_bitset.insert(deleted_doc);
+                    delete_bitset.insert(deleted_doc as usize);
                     might_have_changed = true;
                 }
             }
@@ -126,60 +126,51 @@ fn compute_deleted_bitset(
     Ok(might_have_changed)
 }
 
-/// Advance delete for the given segment up to the target opstamp.
-///
-/// Note that there are no guarantee that the resulting `segment_entry` delete_opstamp
-/// is `==` target_opstamp.
-/// For instance, there was no delete operation between the state of the `segment_entry` and
-/// the `target_opstamp`, `segment_entry` is not updated.
+/// Advance delete for the given segment up
+/// to the target opstamp.
 pub(crate) fn advance_deletes(
     mut segment: Segment,
     segment_entry: &mut SegmentEntry,
     target_opstamp: Opstamp,
 ) -> crate::Result<()> {
-    if segment_entry.meta().delete_opstamp() == Some(target_opstamp) {
-        // We are already up-to-date here.
-        return Ok(());
-    }
+    {
+        if segment_entry.meta().delete_opstamp() == Some(target_opstamp) {
+            // We are already up-to-date here.
+            return Ok(());
+        }
 
-    if segment_entry.delete_bitset().is_none() && segment_entry.delete_cursor().get().is_none() {
-        // There has been no `DeleteOperation` between the segment status and `target_opstamp`.
-        return Ok(());
-    }
+        let segment_reader = SegmentReader::open(&segment)?;
 
-    let segment_reader = SegmentReader::open(&segment)?;
+        let max_doc = segment_reader.max_doc();
+        let mut delete_bitset: BitSet = match segment_entry.delete_bitset() {
+            Some(previous_delete_bitset) => (*previous_delete_bitset).clone(),
+            None => BitSet::with_capacity(max_doc as usize),
+        };
 
-    let max_doc = segment_reader.max_doc();
-    let mut delete_bitset: BitSet = match segment_entry.delete_bitset() {
-        Some(previous_delete_bitset) => (*previous_delete_bitset).clone(),
-        None => BitSet::with_max_value(max_doc),
-    };
+        let delete_cursor = segment_entry.delete_cursor();
+        compute_deleted_bitset(
+            &mut delete_bitset,
+            &segment_reader,
+            delete_cursor,
+            &DocToOpstampMapping::None,
+            target_opstamp,
+        )?;
 
-    compute_deleted_bitset(
-        &mut delete_bitset,
-        &segment_reader,
-        segment_entry.delete_cursor(),
-        &DocToOpstampMapping::None,
-        target_opstamp,
-    )?;
-
-    // TODO optimize
-    if let Some(seg_delete_bitset) = segment_reader.delete_bitset() {
+        // TODO optimize
         for doc in 0u32..max_doc {
-            if seg_delete_bitset.is_deleted(doc) {
-                delete_bitset.insert(doc);
+            if segment_reader.is_deleted(doc) {
+                delete_bitset.insert(doc as usize);
             }
         }
-    }
 
-    let num_deleted_docs = delete_bitset.len();
-    if num_deleted_docs > 0 {
-        segment = segment.with_delete_meta(num_deleted_docs as u32, target_opstamp);
-        let mut delete_file = segment.open_write(SegmentComponent::DELETE)?;
-        write_delete_bitset(&delete_bitset, max_doc, &mut delete_file)?;
-        delete_file.terminate()?;
+        let num_deleted_docs = delete_bitset.len();
+        if num_deleted_docs > 0 {
+            segment = segment.with_delete_meta(num_deleted_docs as u32, target_opstamp);
+            let mut delete_file = segment.open_write(SegmentComponent::DELETE)?;
+            write_delete_bitset(&delete_bitset, max_doc, &mut delete_file)?;
+            delete_file.terminate()?;
+        }
     }
-
     segment_entry.set_meta(segment.meta().clone());
     Ok(())
 }
@@ -245,7 +236,7 @@ fn apply_deletes(
     mut delete_cursor: &mut DeleteCursor,
     doc_opstamps: &[Opstamp],
     last_docstamp: Opstamp,
-) -> crate::Result<Option<BitSet>> {
+) -> crate::Result<Option<BitSet<u32>>> {
     if delete_cursor.get().is_none() {
         // if there are no delete operation in the queue, no need
         // to even open the segment.
@@ -255,7 +246,7 @@ fn apply_deletes(
     let doc_to_opstamps = DocToOpstampMapping::from(doc_opstamps);
 
     let max_doc = segment.meta().max_doc();
-    let mut deleted_bitset = BitSet::with_max_value(max_doc);
+    let mut deleted_bitset = BitSet::with_capacity(max_doc as usize);
     let may_have_deletes = compute_deleted_bitset(
         &mut deleted_bitset,
         &segment_reader,
@@ -514,13 +505,9 @@ impl IndexWriter {
     /// Merges a given list of segments
     ///
     /// `segment_ids` is required to be non-empty.
-    pub fn merge(
-        &mut self,
-        segment_ids: &[SegmentId],
-    ) -> impl Future<Output = crate::Result<SegmentMeta>> {
+    pub async fn merge(&mut self, segment_ids: &[SegmentId]) -> crate::Result<SegmentMeta> {
         let merge_operation = self.segment_updater.make_merge_operation(segment_ids);
-        let segment_updater = self.segment_updater.clone();
-        async move { segment_updater.start_merge(merge_operation)?.await }
+        self.segment_updater.start_merge(merge_operation)?.await
     }
 
     /// Closes the current document channel send.

src/indexer/merger.rs

@@ -1492,46 +1492,4 @@ mod tests {
             assert_eq!(&vals, &[20]);
         }
     }
-
-    #[test]
-    fn merges_f64_fast_fields_correctly() -> crate::Result<()> {
-        let mut builder = schema::SchemaBuilder::new();
-
-        let fast_multi = IntOptions::default().set_fast(Cardinality::MultiValues);
-
-        let field = builder.add_f64_field("f64", schema::FAST);
-        let multi_field = builder.add_f64_field("f64s", fast_multi);
-
-        let index = Index::create_in_ram(builder.build());
-
-        let mut writer = index.writer_with_num_threads(1, 3_000_000)?;
-
-        // Make sure we'll attempt to merge every created segment
-        let mut policy = crate::indexer::LogMergePolicy::default();
-        policy.set_min_merge_size(2);
-        writer.set_merge_policy(Box::new(policy));
-
-        for i in 0..100 {
-            let mut doc = Document::new();
-            doc.add_f64(field, 42.0);
-
-            doc.add_f64(multi_field, 0.24);
-            doc.add_f64(multi_field, 0.27);
-
-            writer.add_document(doc);
-
-            if i % 5 == 0 {
-                writer.commit()?;
-            }
-        }
-
-        writer.commit()?;
-        writer.wait_merging_threads()?;
-
-        // If a merging thread fails, we should end up with more
-        // than one segment here
-        assert_eq!(1, index.searchable_segments()?.len());
-
-        Ok(())
-    }
 }

src/indexer/mod.rs

@@ -33,7 +33,6 @@ pub type DefaultMergePolicy = LogMergePolicy;
 mod tests {
     use crate::schema::{self, Schema};
     use crate::{Index, Term};
-
     #[test]
     fn test_advance_delete_bug() {
         let mut schema_builder = Schema::builder();

src/indexer/segment_entry.rs

@@ -1,7 +1,7 @@
-use crate::common::BitSet;
 use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::indexer::delete_queue::DeleteCursor;
+use bit_set::BitSet;
 use std::fmt;
 
 /// A segment entry describes the state of

src/indexer/segment_serializer.rs

@@ -1,13 +1,10 @@
-use crate::Directory;
+use crate::Result;
 
 use crate::core::Segment;
 use crate::core::SegmentComponent;
-use crate::directory::error::OpenWriteError;
-use crate::directory::{DirectoryClone, RAMDirectory, TerminatingWrite, WritePtr};
 use crate::fastfield::FastFieldSerializer;
 use crate::fieldnorm::FieldNormsSerializer;
 use crate::postings::InvertedIndexSerializer;
-use crate::schema::Schema;
 use crate::store::StoreWriter;
 
 /// Segment serializer is in charge of laying out on disk
@@ -17,50 +14,25 @@ pub struct SegmentSerializer {
     fast_field_serializer: FastFieldSerializer,
     fieldnorms_serializer: FieldNormsSerializer,
     postings_serializer: InvertedIndexSerializer,
-    bundle_writer: Option<(RAMDirectory, WritePtr)>,
-}
-
-pub(crate) struct SegmentSerializerWriters {
-    postings_wrt: WritePtr,
-    positions_skip_wrt: WritePtr,
-    positions_wrt: WritePtr,
-    terms_wrt: WritePtr,
-    fast_field_wrt: WritePtr,
-    fieldnorms_wrt: WritePtr,
-    store_wrt: WritePtr,
-}
-
-impl SegmentSerializerWriters {
-    pub(crate) fn for_segment(segment: &mut Segment) -> Result<Self, OpenWriteError> {
-        Ok(SegmentSerializerWriters {
-            postings_wrt: segment.open_write(SegmentComponent::POSTINGS)?,
-            positions_skip_wrt: segment.open_write(SegmentComponent::POSITIONS)?,
-            positions_wrt: segment.open_write(SegmentComponent::POSITIONSSKIP)?,
-            terms_wrt: segment.open_write(SegmentComponent::TERMS)?,
-            fast_field_wrt: segment.open_write(SegmentComponent::FASTFIELDS)?,
-            fieldnorms_wrt: segment.open_write(SegmentComponent::FIELDNORMS)?,
-            store_wrt: segment.open_write(SegmentComponent::STORE)?,
-        })
-    }
 }
 
 impl SegmentSerializer {
-    pub(crate) fn new(schema: Schema, writers: SegmentSerializerWriters) -> crate::Result<Self> {
-        let fast_field_serializer = FastFieldSerializer::from_write(writers.fast_field_wrt)?;
-        let fieldnorms_serializer = FieldNormsSerializer::from_write(writers.fieldnorms_wrt)?;
-        let postings_serializer = InvertedIndexSerializer::open(
-            schema,
-            writers.terms_wrt,
-            writers.postings_wrt,
-            writers.positions_wrt,
-            writers.positions_skip_wrt,
-        );
+    /// Creates a new `SegmentSerializer`.
+    pub fn for_segment(segment: &mut Segment) -> Result<SegmentSerializer> {
+        let store_write = segment.open_write(SegmentComponent::STORE)?;
+
+        let fast_field_write = segment.open_write(SegmentComponent::FASTFIELDS)?;
+        let fast_field_serializer = FastFieldSerializer::from_write(fast_field_write)?;
+
+        let fieldnorms_write = segment.open_write(SegmentComponent::FIELDNORMS)?;
+        let fieldnorms_serializer = FieldNormsSerializer::from_write(fieldnorms_write)?;
+
+        let postings_serializer = InvertedIndexSerializer::open(segment)?;
         Ok(SegmentSerializer {
-            store_writer: StoreWriter::new(writers.store_wrt),
+            store_writer: StoreWriter::new(store_write),
             fast_field_serializer,
             fieldnorms_serializer,
             postings_serializer,
-            bundle_writer: None,
         })
     }
 
@@ -85,15 +57,11 @@ impl SegmentSerializer {
     }
 
     /// Finalize the segment serialization.
-    pub fn close(mut self) -> crate::Result<()> {
+    pub fn close(self) -> Result<()> {
         self.fast_field_serializer.close()?;
         self.postings_serializer.close()?;
         self.store_writer.close()?;
         self.fieldnorms_serializer.close()?;
-        if let Some((ram_directory, mut bundle_wrt)) = self.bundle_writer.take() {
-            ram_directory.serialize_bundle(&mut bundle_wrt)?;
-            bundle_wrt.terminate()?;
-        }
         Ok(())
     }
 }

src/indexer/segment_updater.rs

@@ -12,7 +12,6 @@ use crate::indexer::index_writer::advance_deletes;
 use crate::indexer::merge_operation::MergeOperationInventory;
 use crate::indexer::merger::IndexMerger;
 use crate::indexer::segment_manager::SegmentsStatus;
-use crate::indexer::segment_serializer::SegmentSerializerWriters;
 use crate::indexer::stamper::Stamper;
 use crate::indexer::SegmentEntry;
 use crate::indexer::SegmentSerializer;
@@ -133,9 +132,7 @@ fn merge(
     let merger: IndexMerger = IndexMerger::open(index.schema(), &segments[..])?;
 
     // ... we just serialize this index merger in our new segment to merge the two segments.
-    let segment_serializer_wrts = SegmentSerializerWriters::for_segment(&mut merged_segment)?;
-    let segment_serializer =
-        SegmentSerializer::new(merged_segment.schema(), segment_serializer_wrts)?;
+    let segment_serializer = SegmentSerializer::for_segment(&mut merged_segment)?;
 
     let num_docs = merger.write(segment_serializer)?;
 
@@ -217,10 +214,6 @@ impl SegmentUpdater {
             self.pool.spawn_ok(async move {
                 let _ = sender.send(f.await);
             });
-        } else {
-            let _ = sender.send(Err(crate::TantivyError::SystemError(
-                "Segment updater killed".to_string(),
-            )));
         }
         receiver.unwrap_or_else(|_| {
             let err_msg =
@@ -333,11 +326,13 @@ impl SegmentUpdater {
     ) -> impl Future<Output = crate::Result<()>> {
         let segment_updater: SegmentUpdater = self.clone();
         self.schedule_future(async move {
-            let segment_entries = segment_updater.purge_deletes(opstamp)?;
-            segment_updater.segment_manager.commit(segment_entries);
-            segment_updater.save_metas(opstamp, payload)?;
-            let _ = garbage_collect_files(segment_updater.clone()).await;
-            segment_updater.consider_merge_options().await;
+            if segment_updater.is_alive() {
+                let segment_entries = segment_updater.purge_deletes(opstamp)?;
+                segment_updater.segment_manager.commit(segment_entries);
+                segment_updater.save_metas(opstamp, payload)?;
+                let _ = garbage_collect_files(segment_updater.clone()).await;
+                segment_updater.consider_merge_options().await;
+            }
             Ok(())
         })
     }

src/indexer/segment_writer.rs

@@ -3,7 +3,7 @@ use crate::core::Segment;
 use crate::core::SerializableSegment;
 use crate::fastfield::FastFieldsWriter;
 use crate::fieldnorm::FieldNormsWriter;
-use crate::indexer::segment_serializer::{SegmentSerializer, SegmentSerializerWriters};
+use crate::indexer::segment_serializer::SegmentSerializer;
 use crate::postings::compute_table_size;
 use crate::postings::MultiFieldPostingsWriter;
 use crate::schema::FieldType;
@@ -69,8 +69,7 @@ impl SegmentWriter {
         schema: &Schema,
     ) -> Result<SegmentWriter> {
         let table_num_bits = initial_table_size(memory_budget)?;
-        let segment_serializer_wrts = SegmentSerializerWriters::for_segment(&mut segment)?;
-        let segment_serializer = SegmentSerializer::new(segment.schema(), segment_serializer_wrts)?;
+        let segment_serializer = SegmentSerializer::for_segment(&mut segment)?;
         let multifield_postings = MultiFieldPostingsWriter::new(schema, table_num_bits);
         let tokenizers = schema
             .fields()

src/lib.rs

@@ -173,7 +173,6 @@ use std::fmt;
 
 use once_cell::sync::Lazy;
 
-/// Index format version.
 const INDEX_FORMAT_VERSION: u32 = 1;
 
 /// Structure version for the index.
@@ -940,73 +939,4 @@ mod tests {
             assert_eq!(fast_field_reader.get(0), 4f64)
         }
     }
-
-    // motivated by #729
-    #[test]
-    fn test_update_via_delete_insert() {
-        use crate::collector::Count;
-        use crate::indexer::NoMergePolicy;
-        use crate::query::AllQuery;
-        use crate::SegmentId;
-        use futures::executor::block_on;
-
-        const DOC_COUNT: u64 = 2u64;
-
-        let mut schema_builder = SchemaBuilder::default();
-        let id = schema_builder.add_u64_field("id", INDEXED);
-        let schema = schema_builder.build();
-
-        let index = Index::create_in_ram(schema.clone());
-        let index_reader = index.reader().unwrap();
-
-        let mut index_writer = index.writer(3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-
-        for doc_id in 0u64..DOC_COUNT {
-            index_writer.add_document(doc!(id => doc_id));
-        }
-        index_writer.commit().unwrap();
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-
-        assert_eq!(
-            searcher.search(&AllQuery, &Count).unwrap(),
-            DOC_COUNT as usize
-        );
-
-        // update the 10 elements by deleting and re-adding
-        for doc_id in 0u64..DOC_COUNT {
-            index_writer.delete_term(Term::from_field_u64(id, doc_id));
-            index_writer.commit().unwrap();
-            index_reader.reload().unwrap();
-            let doc = doc!(id =>  doc_id);
-            index_writer.add_document(doc);
-            index_writer.commit().unwrap();
-            index_reader.reload().unwrap();
-            let searcher = index_reader.searcher();
-            // The number of document should be stable.
-            assert_eq!(
-                searcher.search(&AllQuery, &Count).unwrap(),
-                DOC_COUNT as usize
-            );
-        }
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-        let segment_ids: Vec<SegmentId> = searcher
-            .segment_readers()
-            .into_iter()
-            .map(|reader| reader.segment_id())
-            .collect();
-        block_on(index_writer.merge(&segment_ids)).unwrap();
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-
-        assert_eq!(
-            searcher.search(&AllQuery, &Count).unwrap(),
-            DOC_COUNT as usize
-        );
-    }
 }

src/postings/mod.rs

@@ -75,7 +75,7 @@ pub mod tests {
         let schema = schema_builder.build();
         let index = Index::create_in_ram(schema);
         let mut segment = index.new_segment();
-        let mut posting_serializer = InvertedIndexSerializer::for_segment(&mut segment).unwrap();
+        let mut posting_serializer = InvertedIndexSerializer::open(&mut segment).unwrap();
         {
             let mut field_serializer = posting_serializer.new_field(text_field, 120 * 4).unwrap();
             field_serializer.new_term("abc".as_bytes()).unwrap();

src/postings/serializer.rs

@@ -10,8 +10,8 @@ use crate::postings::USE_SKIP_INFO_LIMIT;
 use crate::schema::Schema;
 use crate::schema::{Field, FieldEntry, FieldType};
 use crate::termdict::{TermDictionaryBuilder, TermOrdinal};
+use crate::DocId;
 use crate::Result;
-use crate::{Directory, DocId};
 use std::io::{self, Write};
 
 /// `InvertedIndexSerializer` is in charge of serializing
@@ -54,36 +54,33 @@ pub struct InvertedIndexSerializer {
 }
 
 impl InvertedIndexSerializer {
-    pub(crate) fn for_segment(segment: &mut Segment) -> crate::Result<Self> {
-        let schema = segment.schema();
-        use crate::core::SegmentComponent;
-        let terms_wrt = segment.open_write(SegmentComponent::TERMS)?;
-        let postings_wrt = segment.open_write(SegmentComponent::POSTINGS)?;
-        let positions_wrt = segment.open_write(SegmentComponent::POSITIONS)?;
-        let positions_idx_wrt = segment.open_write(SegmentComponent::POSITIONSSKIP)?;
-        Ok(Self::open(
-            schema,
-            terms_wrt,
-            postings_wrt,
-            positions_wrt,
-            positions_idx_wrt,
-        ))
-    }
-    /// Open a new `PostingsSerializer` for the given segment
-    pub(crate) fn open(
+    /// Open a new `InvertedIndexSerializer` for the given segment
+    fn create(
+        terms_write: CompositeWrite<WritePtr>,
+        postings_write: CompositeWrite<WritePtr>,
+        positions_write: CompositeWrite<WritePtr>,
+        positionsidx_write: CompositeWrite<WritePtr>,
         schema: Schema,
-        terms_wrt: WritePtr,
-        postings_wrt: WritePtr,
-        positions_wrt: WritePtr,
-        positions_idx_wrt: WritePtr,
-    ) -> InvertedIndexSerializer {
-        InvertedIndexSerializer {
-            terms_write: CompositeWrite::wrap(terms_wrt),
-            postings_write: CompositeWrite::wrap(postings_wrt),
-            positions_write: CompositeWrite::wrap(positions_wrt),
-            positionsidx_write: CompositeWrite::wrap(positions_idx_wrt),
+    ) -> Result<InvertedIndexSerializer> {
+        Ok(InvertedIndexSerializer {
+            terms_write,
+            postings_write,
+            positions_write,
+            positionsidx_write,
             schema,
-        }
+        })
+    }
+
+    /// Open a new `PostingsSerializer` for the given segment
+    pub fn open(segment: &mut Segment) -> Result<InvertedIndexSerializer> {
+        use crate::SegmentComponent::{POSITIONS, POSITIONSSKIP, POSTINGS, TERMS};
+        InvertedIndexSerializer::create(
+            CompositeWrite::wrap(segment.open_write(TERMS)?),
+            CompositeWrite::wrap(segment.open_write(POSTINGS)?),
+            CompositeWrite::wrap(segment.open_write(POSITIONS)?),
+            CompositeWrite::wrap(segment.open_write(POSITIONSSKIP)?),
+            segment.schema(),
+        )
     }
 
     /// Must be called before starting pushing terms of

src/query/query_parser/query_parser.rs

@@ -8,7 +8,7 @@ use crate::query::PhraseQuery;
 use crate::query::Query;
 use crate::query::RangeQuery;
 use crate::query::TermQuery;
-use crate::schema::{Facet, IndexRecordOption};
+use crate::schema::IndexRecordOption;
 use crate::schema::{Field, Schema};
 use crate::schema::{FieldType, Term};
 use crate::tokenizer::TokenizerManager;
@@ -319,10 +319,7 @@ impl QueryParser {
                     ))
                 }
             }
-            FieldType::HierarchicalFacet => {
-                let facet = Facet::from_text(phrase);
-                Ok(vec![(0, Term::from_field_text(field, facet.encoded_str()))])
-            }
+            FieldType::HierarchicalFacet => Ok(vec![(0, Term::from_field_text(field, phrase))]),
             FieldType::Bytes => {
                 let field_name = self.schema.get_field_name(field).to_string();
                 Err(QueryParserError::FieldNotIndexed(field_name))
@@ -557,7 +554,6 @@ mod test {
         schema_builder.add_text_field("with_stop_words", text_options);
         schema_builder.add_date_field("date", INDEXED);
         schema_builder.add_f64_field("float", INDEXED);
-        schema_builder.add_facet_field("facet");
         let schema = schema_builder.build();
         let default_fields = vec![title, text];
         let tokenizer_manager = TokenizerManager::default();
@@ -592,13 +588,9 @@ mod test {
     }
 
     #[test]
-    pub fn test_parse_query_facet() {
+    pub fn test_parse_query_simple() {
         let query_parser = make_query_parser();
-        let query = query_parser.parse_query("facet:/root/branch/leaf").unwrap();
-        assert_eq!(
-            format!("{:?}", query),
-            "TermQuery(Term(field=11,bytes=[114, 111, 111, 116, 0, 98, 114, 97, 110, 99, 104, 0, 108, 101, 97, 102]))"
-        );
+        assert!(query_parser.parse_query("toto").is_ok());
     }
 
     #[test]

src/schema/schema.rs

@@ -166,7 +166,7 @@ impl SchemaBuilder {
     }
 
     /// Adds a field entry to the schema in build.
-    pub fn add_field(&mut self, field_entry: FieldEntry) -> Field {
+    fn add_field(&mut self, field_entry: FieldEntry) -> Field {
         let field = Field::from_field_id(self.fields.len() as u32);
         let field_name = field_entry.name().to_string();
         self.fields.push(field_entry);
@@ -401,7 +401,6 @@ pub enum DocParsingError {
 mod tests {
 
     use crate::schema::field_type::ValueParsingError;
-    use crate::schema::int_options::Cardinality::SingleValue;
     use crate::schema::schema::DocParsingError::NotJSON;
     use crate::schema::*;
     use matches::{assert_matches, matches};
@@ -716,94 +715,4 @@ mod tests {
             assert_matches!(json_err, Err(NotJSON(_)));
         }
     }
-
-    #[test]
-    pub fn test_schema_add_field() {
-        let mut schema_builder = SchemaBuilder::default();
-        let id_options = TextOptions::default().set_stored().set_indexing_options(
-            TextFieldIndexing::default()
-                .set_tokenizer("raw")
-                .set_index_option(IndexRecordOption::Basic),
-        );
-        let timestamp_options = IntOptions::default()
-            .set_stored()
-            .set_indexed()
-            .set_fast(SingleValue);
-        schema_builder.add_text_field("_id", id_options);
-        schema_builder.add_date_field("_timestamp", timestamp_options);
-
-        let schema_content = r#"[
-  {
-    "name": "text",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "position",
-        "tokenizer": "default"
-      },
-      "stored": false
-    }
-  },
-  {
-    "name": "popularity",
-    "type": "i64",
-    "options": {
-      "indexed": false,
-      "fast": "single",
-      "stored": true
-    }
-  }
-]"#;
-        let tmp_schema: Schema =
-            serde_json::from_str(&schema_content).expect("error while reading json");
-        for (_field, field_entry) in tmp_schema.fields() {
-            schema_builder.add_field(field_entry.clone());
-        }
-
-        let schema = schema_builder.build();
-        let schema_json = serde_json::to_string_pretty(&schema).unwrap();
-        let expected = r#"[
-  {
-    "name": "_id",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "basic",
-        "tokenizer": "raw"
-      },
-      "stored": true
-    }
-  },
-  {
-    "name": "_timestamp",
-    "type": "date",
-    "options": {
-      "indexed": true,
-      "fast": "single",
-      "stored": true
-    }
-  },
-  {
-    "name": "text",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "position",
-        "tokenizer": "default"
-      },
-      "stored": false
-    }
-  },
-  {
-    "name": "popularity",
-    "type": "i64",
-    "options": {
-      "indexed": false,
-      "fast": "single",
-      "stored": true
-    }
-  }
-]"#;
-        assert_eq!(schema_json, expected);
-    }
 }

src/schema/value.rs

@@ -209,8 +209,8 @@ impl From<f64> for Value {
     }
 }
 
-impl From<crate::DateTime> for Value {
-    fn from(date_time: crate::DateTime) -> Value {
+impl From<DateTime> for Value {
+    fn from(date_time: DateTime) -> Value {
         Value::Date(date_time)
     }
 }

src/store/compression_snap.rs

@@ -5,7 +5,7 @@ use std::io::{self, Read, Write};
 /// Name of the compression scheme used in the doc store.
 ///
 /// This name is appended to the version string of tantivy.
-pub const COMPRESSION: &str = "snappy";
+pub const COMPRESSION: &'static str = "snappy";
 
 pub fn compress(uncompressed: &[u8], compressed: &mut Vec<u8>) -> io::Result<()> {
     compressed.clear();

src/store/mod.rs

@@ -57,7 +57,7 @@ use self::compression_snap::{compress, decompress};
 pub mod tests {
 
     use super::*;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+    use crate::directory::{Directory, RAMDirectory, WritePtr};
     use crate::schema::Document;
     use crate::schema::FieldValue;
     use crate::schema::Schema;

src/termdict/mod.rs

@@ -36,7 +36,7 @@ pub use self::termdict::{TermDictionary, TermDictionaryBuilder};
 mod tests {
     use super::{TermDictionary, TermDictionaryBuilder, TermStreamer};
     use crate::core::Index;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, ReadOnlySource};
+    use crate::directory::{Directory, RAMDirectory, ReadOnlySource};
     use crate::postings::TermInfo;
     use crate::schema::{Document, FieldType, Schema, TEXT};
     use std::path::PathBuf;

tests/failpoints/mod.rs

@@ -1,8 +1,6 @@
 use fail;
 use std::path::Path;
-use tantivy::directory::{
-    Directory, ManagedDirectory, RAMDirectory, ReadOnlyDirectory, TerminatingWrite,
-};
+use tantivy::directory::{Directory, ManagedDirectory, RAMDirectory, TerminatingWrite};
 use tantivy::doc;
 use tantivy::schema::{Schema, TEXT};
 use tantivy::{Index, Term};