Replace lazy_static with std::sync::OnceLock (#301)

* Replace lazy_static with once_cell

* Replace once_cell with std::sync::OnceLock

refinery_core/Cargo.toml

@@ -19,7 +19,6 @@ mysql_async = ["dep:mysql_async"]
 [dependencies]
 async-trait = "0.1"
 cfg-if = "1.0"
-lazy_static = "1"
 log = "0.4"
 regex = "1"
 serde = { version = "1", features = ["derive"] }

refinery_core/src/runner.rs

@@ -5,19 +5,17 @@ use time::OffsetDateTime;
 use std::cmp::Ordering;
 use std::fmt;
 use std::hash::{Hash, Hasher};
+use std::sync::OnceLock;
 
 use crate::error::Kind;
 use crate::traits::DEFAULT_MIGRATION_TABLE_NAME;
 use crate::{AsyncMigrate, Error, Migrate};
 use std::fmt::Formatter;
 
 // regex used to match file names
-pub fn file_match_re() -> Regex {
-    Regex::new(r"^([U|V])(\d+(?:\.\d+)?)__(\w+)").unwrap()
-}
-
-lazy_static::lazy_static! {
-    static ref RE: regex::Regex = file_match_re();
+pub fn file_match_re() -> &'static Regex {
+    static RE: OnceLock<regex::Regex> = OnceLock::new();
+    RE.get_or_init(|| Regex::new(r"^([U|V])(\d+(?:\.\d+)?)__(\w+)").unwrap())
 }
 
 /// An enum set that represents the type of the Migration
@@ -84,7 +82,7 @@ impl Migration {
     /// Create an unapplied migration, name and version are parsed from the input_name,
     /// which must be named in the format (U|V){1}__{2}.rs where {1} represents the migration version and {2} the name.
     pub fn unapplied(input_name: &str, sql: &str) -> Result<Migration, Error> {
-        let captures = RE
+        let captures = file_match_re()
             .captures(input_name)
             .filter(|caps| caps.len() == 4)
             .ok_or_else(|| Error::new(Kind::InvalidName, None))?;

refinery_core/src/util.rs

@@ -4,10 +4,6 @@ use std::ffi::OsStr;
 use std::path::{Path, PathBuf};
 use walkdir::{DirEntry, WalkDir};
 
-lazy_static::lazy_static! {
-    static ref RE: regex::Regex = Regex::new(r"^(U|V)(\d+(?:\.\d+)?)__\w+\.(rs|sql)$").unwrap();
-}
-
 /// enum containing the migration types used to search for migrations
 /// either just .sql files or both .sql and .rs
 pub enum MigrationType {