feat: Create a strong DocumentId type

Forcing it to be something internal will permit to avoid possible miss comparisons to be done with other types.

src/database/blob/positive/blob.rs

@@ -201,13 +201,16 @@ impl<W: Write, X: Write> PositiveBlobBuilder<W, X> {
 #[cfg(test)]
 mod tests {
     use super::*;
+
     use std::error::Error;
 
+    use crate::DocumentId;
+
     #[test]
     fn serialize_deserialize() -> Result<(), Box<Error>> {
-        let a = DocIndex { document_id: 0, attribute: 3, attribute_index: 11 };
-        let b = DocIndex { document_id: 1, attribute: 4, attribute_index: 21 };
-        let c = DocIndex { document_id: 2, attribute: 8, attribute_index: 2 };
+        let a = DocIndex { document_id: DocumentId(0), attribute: 3, attribute_index: 11 };
+        let b = DocIndex { document_id: DocumentId(1), attribute: 4, attribute_index: 21 };
+        let c = DocIndex { document_id: DocumentId(2), attribute: 8, attribute_index: 2 };
 
         let mut builder = PositiveBlobBuilder::memory();
 
@@ -228,9 +231,9 @@ mod tests {
 
     #[test]
     fn serde_serialize_deserialize() -> Result<(), Box<Error>> {
-        let a = DocIndex { document_id: 0, attribute: 3, attribute_index: 11 };
-        let b = DocIndex { document_id: 1, attribute: 4, attribute_index: 21 };
-        let c = DocIndex { document_id: 2, attribute: 8, attribute_index: 2 };
+        let a = DocIndex { document_id: DocumentId(0), attribute: 3, attribute_index: 11 };
+        let b = DocIndex { document_id: DocumentId(1), attribute: 4, attribute_index: 21 };
+        let c = DocIndex { document_id: DocumentId(2), attribute: 8, attribute_index: 2 };
 
         let mut builder = PositiveBlobBuilder::memory();
 

src/database/database_view.rs

@@ -100,7 +100,7 @@ where D: Deref<Target=DB>
 {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let mut options = ReadOptions::new();
-        let lower = DocumentKey::new(0);
+        let lower = DocumentKey::new(DocumentId(0));
         options.set_iterate_lower_bound(lower.as_ref());
 
         let mut iter = self.snapshot.iter_opt(options);

src/database/document_key.rs

@@ -19,7 +19,7 @@ impl DocumentKey {
 
         let mut wtr = Cursor::new(&mut buffer[..]);
         wtr.write_all(b"doc-").unwrap();
-        wtr.write_u64::<NativeEndian>(id).unwrap();
+        wtr.write_u64::<NativeEndian>(id.0).unwrap();
 
         DocumentKey(buffer)
     }
@@ -43,7 +43,8 @@ impl DocumentKey {
     }
 
     pub fn document_id(&self) -> DocumentId {
-        (&self.0[4..]).read_u64::<NativeEndian>().unwrap()
+        let id = (&self.0[4..]).read_u64::<NativeEndian>().unwrap();
+        DocumentId(id)
     }
 }
 
@@ -88,7 +89,8 @@ impl DocumentKeyAttr {
     }
 
     pub fn document_id(&self) -> DocumentId {
-        (&self.0[4..]).read_u64::<NativeEndian>().unwrap()
+        let id = (&self.0[4..]).read_u64::<NativeEndian>().unwrap();
+        DocumentId(id)
     }
 
     pub fn attribute(&self) -> SchemaAttr {

src/database/mod.rs

@@ -194,6 +194,7 @@ mod tests {
     use serde_derive::{Serialize, Deserialize};
     use tempfile::tempdir;
 
+    use crate::DocumentId;
     use crate::tokenizer::DefaultBuilder;
     use crate::database::update::PositiveUpdateBuilder;
     use crate::database::schema::{SchemaBuilder, STORED, INDEXED};
@@ -238,8 +239,8 @@ mod tests {
         let mut update = {
             let mut builder = PositiveUpdateBuilder::new(update_path, schema, tokenizer_builder);
 
-            builder.update(0, &doc0).unwrap();
-            builder.update(1, &doc1).unwrap();
+            builder.update(DocumentId(0), &doc0).unwrap();
+            builder.update(DocumentId(1), &doc1).unwrap();
 
             builder.build()?
         };
@@ -248,8 +249,8 @@ mod tests {
         database.ingest_update_file(update)?;
         let view = database.view();
 
-        let de_doc0: SimpleDoc = view.retrieve_document(0)?;
-        let de_doc1: SimpleDoc = view.retrieve_document(1)?;
+        let de_doc0: SimpleDoc = view.retrieve_document(DocumentId(0))?;
+        let de_doc1: SimpleDoc = view.retrieve_document(DocumentId(1))?;
 
         assert_eq!(doc0, de_doc0);
         assert_eq!(doc1, de_doc1);

src/database/update/negative/unordered_builder.rs

@@ -30,7 +30,7 @@ impl<W: io::Write> UnorderedNegativeBlobBuilder<W> {
 
     pub fn into_inner(mut self) -> io::Result<W> {
         for id in self.doc_ids {
-            self.wrt.write_u64::<NativeEndian>(id)?;
+            self.wrt.write_u64::<NativeEndian>(id.0)?;
         }
         Ok(self.wrt)
     }