Replace lazy_static with once_cell

Author: DrSensor

.github/main.workflow

@@ -53,7 +53,7 @@ action "Test all rust project" {
 
 action "Smoke tests" {
 	needs = "Test all rust project"
-	uses = "docker://node:slim-buster"
+	uses = "docker://node:buster-slim"
 	runs = "./.github/entrypoint.sh"
 	args = [
 		"npm install",

Cargo.lock

@@ -15,9 +15,12 @@ edition = "2018"
 pest = "2"
 pest_derive = "2"
 # helper
-lazy_static = "1" # to define the global caches
 either = "1" # a workaround for iterator.filter that return Result<Vec, _>
 static_assertions = "0.3" # design-by-contract at compile time
 
+[dependencies.once_cell] # to define the global caches
+version = "0.2"
+default-features = false # disable parking_lot
+
 [badges]
 maintenance = { status = "actively-developed" }

packages/core/Cargo.toml

@@ -1,18 +1,16 @@
 //! Collection of cache variables which help detecting semantics error.
 // TODO: 🤔 use hot reload https://crates.rs/crates/warmy when import statement is introduced
 use crate::error::Error;
-use lazy_static::lazy_static;
+use once_cell::sync::Lazy;
 use std::{collections::HashMap, sync::*};
 
 // TODO: replace with https://github.com/rust-lang-nursery/lazy-static.rs/issues/111 when resolved
 // 🤔 or is there any better way?
 // pub static mut TRANSITION: Option<HashMap<Transition, &str>> = None; // doesn't work!
 // type LazyMut<T> = Mutex<Option<T>>;
-lazy_static! {
-	static ref TRANSITION: Mutex<MapTransition> = Mutex::new(HashMap::new());
-	static ref WARNING: RwLock<String> = RwLock::new(String::new());
-	/*reserved for another caches*/
-}
+static TRANSITION: Lazy<Mutex<MapTransition>> = Lazy::new(|| Mutex::new(HashMap::new()));
+static WARNING: Lazy<RwLock<String>> = Lazy::new(|| RwLock::new(String::new()));
+/*reserved for another caches*/
 
 /// Access cached transition safely
 pub fn transition<'a>() -> Result<MutexGuard<'a, MapTransition>, Error> {