feat: support prefix query on name field (#694)

* feat: support prefix phase query on name field

* update changelog

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Notice
 * llama.cpp backend (CPU, Metal) now requires a redownload of gguf model due to upstream format changes: https://github.com/TabbyML/tabby/pull/645 https://github.com/ggerganov/llama.cpp/pull/3252
+* Due to indexing format changes, the `~/.tabby/index` needs to be manually removed before any further runs of `tabby scheduler`.
 
 ## Features
 

crates/tabby-common/src/index.rs

@@ -1,5 +1,5 @@
 use tantivy::{
-    tokenizer::{RegexTokenizer, RemoveLongFilter, TextAnalyzer},
+    tokenizer::{NgramTokenizer, RegexTokenizer, RemoveLongFilter, TextAnalyzer},
     Index,
 };
 
@@ -8,6 +8,7 @@ pub trait IndexExt {
 }
 
 pub static CODE_TOKENIZER: &str = "code";
+pub static IDENTIFIER_TOKENIZER: &str = "identifier";
 
 impl IndexExt for Index {
     fn register_tokenizer(&self) {
@@ -16,5 +17,11 @@ impl IndexExt for Index {
             .build();
 
         self.tokenizers().register(CODE_TOKENIZER, code_tokenizer);
+
+        let identifier_tokenzier =
+            TextAnalyzer::builder(NgramTokenizer::prefix_only(2, 5).unwrap()).build();
+
+        self.tokenizers()
+            .register(IDENTIFIER_TOKENIZER, identifier_tokenzier);
     }
 }

crates/tabby-scheduler/src/index.rs

@@ -3,7 +3,7 @@ use std::fs;
 use anyhow::Result;
 use tabby_common::{
     config::Config,
-    index::{IndexExt, CODE_TOKENIZER},
+    index::{IndexExt, CODE_TOKENIZER, IDENTIFIER_TOKENIZER},
     path::index_dir,
     SourceFile,
 };
@@ -29,10 +29,17 @@ pub fn index_repositories(_config: &Config) -> Result<()> {
         .set_indexing_options(code_indexing_options)
         .set_stored();
 
+    let name_indexing_options = TextFieldIndexing::default()
+        .set_tokenizer(IDENTIFIER_TOKENIZER)
+        .set_index_option(tantivy::schema::IndexRecordOption::WithFreqsAndPositions);
+    let name_options = TextOptions::default()
+        .set_indexing_options(name_indexing_options)
+        .set_stored();
+
     let field_git_url = builder.add_text_field("git_url", STRING | STORED);
     let field_filepath = builder.add_text_field("filepath", STRING | STORED);
     let field_language = builder.add_text_field("language", STRING | STORED);
-    let field_name = builder.add_text_field("name", STRING | STORED);
+    let field_name = builder.add_text_field("name", name_options);
     let field_kind = builder.add_text_field("kind", STRING | STORED);
     let field_body = builder.add_text_field("body", code_options);