feat: support regex with r/.../ syntax (#1745)

* feat: support regex with r/.../ syntax

* cargo fmt

* feat(tests): add some tests for regex matching

4 files changed, 125 insertions, 18 deletions

diff --git a/Cargo.lock b/Cargo.lock
index ab0eaa31..50ffc518 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -245,7 +245,6 @@ dependencies = [
  "indicatif",
  "interim",
  "itertools",
- "lazy_static",
  "log",
  "memchr",
  "minspan",
@@ -3510,6 +3509,7 @@ dependencies = [
  "libsqlite3-sys",
  "log",
  "percent-encoding",
+ "regex",
  "serde",
  "sqlx-core",
  "time",
diff --git a/atuin-client/Cargo.toml b/atuin-client/Cargo.toml
index 51227044..e2353daf 100644
--- a/atuin-client/Cargo.toml
+++ b/atuin-client/Cargo.toml
@@ -37,13 +37,12 @@ async-trait = { workspace = true }
 itertools = { workspace = true }
 rand = { workspace = true }
 shellexpand = "3"
-sqlx = { workspace = true, features = ["sqlite"] }
+sqlx = { workspace = true, features = ["sqlite", "regexp"] }
 minspan = "0.1.1"
 regex = "1.9.1"
 serde_regex = "1.1.0"
 fs-err = { workspace = true }
 sql-builder = "3"
-lazy_static = "1"
 memchr = "2.5"
 rmp = { version = "0.8.11" }
 typed-builder = { workspace = true }
diff --git a/atuin-client/src/database.rs b/atuin-client/src/database.rs
index 572955f8..2be27ac8 100644
--- a/atuin-client/src/database.rs
+++ b/atuin-client/src/database.rs
@@ -1,4 +1,5 @@
 use std::{
+    borrow::Cow,
     env,
     path::{Path, PathBuf},
     str::FromStr,
@@ -9,10 +10,8 @@ use async_trait::async_trait;
 use atuin_common::utils;
 use fs_err as fs;
 use itertools::Itertools;
-use lazy_static::lazy_static;
 use rand::{distributions::Alphanumeric, Rng};
-use regex::Regex;
-use sql_builder::{esc, quote, SqlBuilder, SqlName};
+use sql_builder::{bind::Bind, esc, quote, SqlBuilder, SqlName};
 use sqlx::{
     sqlite::{
         SqliteConnectOptions, SqliteJournalMode, SqlitePool, SqlitePoolOptions, SqliteRow,
@@ -142,6 +141,7 @@ impl Sqlite {
             .journal_mode(SqliteJournalMode::Wal)
             .optimize_on_close(true, None)
             .synchronous(SqliteSynchronous::Normal)
+            .with_regexp()
             .create_if_missing(true);
 
         let pool = SqlitePoolOptions::new()
@@ -428,18 +428,42 @@ impl Database for Sqlite {
         };
 
         let orig_query = query;
-        let query = query.replace('*', "%"); // allow wildcard char
 
+        let mut regexes = Vec::new();
         match search_mode {
-            SearchMode::Prefix => sql.and_where_like_left("command", query),
+            SearchMode::Prefix => sql.and_where_like_left("command", query.replace('*', "%")),
             _ => {
-                // don't recompile the regex on successive calls!
-                lazy_static! {
-                    static ref SPLIT_REGEX: Regex = Regex::new(r" +").unwrap();
-                }
-
                 let mut is_or = false;
-                for query_part in SPLIT_REGEX.split(query.as_str()) {
+                let mut regex = None;
+                for part in query.split_inclusive(' ') {
+                    let query_part: Cow<str> = match (&mut regex, part.starts_with("r/")) {
+                        (None, false) => {
+                            if part.trim_end().is_empty() {
+                                continue;
+                            }
+                            Cow::Owned(part.trim_end().replace('*', "%")) // allow wildcard char
+                        }
+                        (None, true) => {
+                            if part[2..].trim_end().ends_with('/') {
+                                let end_pos = part.trim_end().len() - 1;
+                                regexes.push(String::from(&part[2..end_pos]));
+                            } else {
+                                regex = Some(String::from(&part[2..]));
+                            }
+                            continue;
+                        }
+                        (Some(r), _) => {
+                            if part.trim_end().ends_with('/') {
+                                let end_pos = part.trim_end().len() - 1;
+                                r.push_str(&part.trim_end()[..end_pos]);
+                                regexes.push(regex.take().unwrap());
+                            } else {
+                                r.push_str(part);
+                            }
+                            continue;
+                        }
+                    };
+
                     // TODO smart case mode could be made configurable like in fzf
                     let (is_glob, glob) = if query_part.contains(char::is_uppercase) {
                         (true, "*")
@@ -448,7 +472,7 @@ impl Database for Sqlite {
                     };
 
                     let (is_inverse, query_part) = match query_part.strip_prefix('!') {
-                        Some(stripped) => (true, stripped),
+                        Some(stripped) => (true, Cow::Borrowed(stripped)),
                         None => (false, query_part),
                     };
 
@@ -477,10 +501,18 @@ impl Database for Sqlite {
                     sql.fuzzy_condition("command", param, is_inverse, is_glob, is_or);
                     is_or = false;
                 }
+                if let Some(r) = regex {
+                    regexes.push(r);
+                }
+
                 &mut sql
             }
         };
 
+        for regex in regexes {
+            sql.and_where("command regexp ?".bind(&regex));
+        }
+
         filter_options
             .exit
             .map(|exit| sql.and_where_eq("exit", exit));
@@ -825,6 +857,71 @@ mod test {
         assert_search_eq(&db, SearchMode::FullText, FilterMode::Global, "hm", 0)
             .await
             .unwrap();
+
+        // regex
+        assert_search_eq(&db, SearchMode::FullText, FilterMode::Global, "r/^ls ", 1)
+            .await
+            .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "r/ls / ie$",
+            1,
+        )
+        .await
+        .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "r/ls / !ie",
+            0,
+        )
+        .await
+        .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "meow r/ls/",
+            0,
+        )
+        .await
+        .unwrap();
+        assert_search_eq(&db, SearchMode::FullText, FilterMode::Global, "r//hom/", 1)
+            .await
+            .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "r//home//",
+            1,
+        )
+        .await
+        .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "r//home///",
+            0,
+        )
+        .await
+        .unwrap();
+        assert_search_eq(&db, SearchMode::FullText, FilterMode::Global, "/home.*e", 0)
+            .await
+            .unwrap();
+        assert_search_eq(
+            &db,
+            SearchMode::FullText,
+            FilterMode::Global,
+            "r/home.*e",
+            1,
+        )
+        .await
+        .unwrap();
     }
 
     #[tokio::test(flavor = "multi_thread")]
@@ -915,6 +1012,17 @@ mod test {
         assert_search_eq(&db, SearchMode::Fuzzy, FilterMode::Global, "Ellie", 1)
             .await
             .unwrap();
+
+        // regex
+        assert_search_eq(&db, SearchMode::Fuzzy, FilterMode::Global, "r/^ls ", 2)
+            .await
+            .unwrap();
+        assert_search_eq(&db, SearchMode::Fuzzy, FilterMode::Global, "r/[Ee]llie", 3)
+            .await
+            .unwrap();
+        assert_search_eq(&db, SearchMode::Fuzzy, FilterMode::Global, "/h/e r/^ls ", 1)
+            .await
+            .unwrap();
     }
 
     #[tokio::test(flavor = "multi_thread")]
diff --git a/atuin/src/command/client/search/engines/db.rs b/atuin/src/command/client/search/engines/db.rs
index b4f24561..e638f9d9 100644
--- a/atuin/src/command/client/search/engines/db.rs
+++ b/atuin/src/command/client/search/engines/db.rs
@@ -26,8 +26,8 @@ impl SearchEngine for Search {
                     ..Default::default()
                 },
             )
-            .await?
-            .into_iter()
-            .collect::<Vec<_>>())
+            .await
+            // ignore errors as it may be caused by incomplete regex
+            .map_or(Vec::new(), |r| r.into_iter().collect()))
     }
 }