(history): Use a different starting id each time (#369)

crates/history/Cargo.toml

@@ -24,6 +24,9 @@ thiserror = { version = "1.0", optional = true }
 version = "0.3"
 features = ["History", "Window", "Location", "Url"]
 
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+getrandom = {version="0.2.10", features = ["js"]}
+
 [dev-dependencies]
 wasm-bindgen-test = "0.3"
 gloo-timers = { version = "0.3.0", features = ["futures"], path = "../timers" }

crates/history/src/utils.rs

@@ -4,12 +4,30 @@ use std::sync::atomic::{AtomicU32, Ordering};
 
 use wasm_bindgen::throw_str;
 
+#[cfg(not(target_arch = "wasm32"))]
 pub(crate) fn get_id() -> u32 {
     static ID_CTR: AtomicU32 = AtomicU32::new(0);
 
     ID_CTR.fetch_add(1, Ordering::SeqCst)
 }
 
+#[cfg(target_arch = "wasm32")]
+pub(crate) fn get_id() -> u32 {
+    static ID_CTR: AtomicU32 = AtomicU32::new(0);
+    static INIT: std::sync::Once = std::sync::Once::new();
+
+    INIT.call_once(|| {
+        let mut start: [u8; 4] = [0; 4];
+        // If it fails then the start is not or only partly filled.
+        // But since this method should not fail, we take what we get.
+        let _ = getrandom::getrandom(&mut start);
+        // Using a high initial value is not an issue as `fetch_add` does wrap around.
+        ID_CTR.store(u32::from_ne_bytes(start), Ordering::SeqCst);
+    });
+
+    ID_CTR.fetch_add(1, Ordering::SeqCst)
+}
+
 pub(crate) fn assert_absolute_path(path: &str) {
     if !path.starts_with('/') {
         throw_str("You cannot use relative path with this history type.");