rustc version is : rustc 1.88.0
const WEB_SERVER2;
const WEB_SERVER;
can't pass the test;
but const change to static can pass test.
use std::sync::Arc;
use std::sync::LazyLock;
const WEB_SERVER2: LazyLock<Arc> = LazyLock::new(|| {
let web = start_web_server(&ResourceWebServerCfg {
host: "localhost".to_string(),
port: 0,
});
Arc::new(web)
});
fn get_web_server2() -> Arc {
(*WEB_SERVER2).clone()
}
#[test]
fn test_once_lock_for_start_server2() {
let w1 = get_web_server2();
let w2 = get_web_server2();
assert_eq!(w1.url, w2.url);
}
use std::sync::OnceLock;
const WEB_SERVER: OnceLock<Arc> = OnceLock::new();
fn get_web_server() -> Arc {
WEB_SERVER
.get_or_init(|| {
let web = start_web_server(&ResourceWebServerCfg {
host: "localhost".to_string(),
port: 8080,
});
Arc::new(web)
})
.clone()
}
#[test]
fn test_once_lock_for_start_server() {
let w1 = get_web_server();
let w2 = get_web_server();
assert_eq!(w1.url, w2.url);
}