Add the wallet_switchEthereumChain method to the eip1193 transport

src/transports/eip_1193.rs

@@ -41,7 +41,7 @@
         let subscriptions: Subscriptions = Subscriptions::default();
         let subscriptions_for_closure = subscriptions.clone();
         let msg_handler = Closure::wrap(Box::new(move |evt_js: JsValue| {
             let evt = evt_js.into_serde::<MessageEvent>().expect("Couldn't parse event data");
             log::trace!("Message from provider: {:?}", evt);
             match evt.event_type.as_str() {
                 "eth_subscription" => {
@@ -71,7 +71,7 @@
     pub fn connect_stream(&self) -> impl Stream<Item = Option<String>> {
         self.handle_ad_hoc_event("connect", |evt_js| {
             let evt = evt_js
                 .into_serde::<ConnectEvent>()
                 .expect("couldn't parse connect event");
             evt.chain_id
         })
@@ -81,7 +81,7 @@
     /// above.
     pub fn disconnect_stream(&self) -> impl Stream<Item = jsonrpc_core::Error> {
         self.handle_ad_hoc_event("disconnect", |evt_js| {
             evt_js.into_serde().expect("deserializing disconnect error failed")
         })
     }
 
@@ -132,6 +132,29 @@
             .into_deserializer();
         O::deserialize(deserializer).expect(&format!("couldn't deserialize {}", name))
     }
+
+    /// EIP-3326: Switch a wallet to another chain
+    pub async fn switch_chain(&self, chain_id: &str) -> Result<serde_json::value::Value, error::Error> {
+        let js_params = JsValue::from_serde(&vec![&ChainId {
+            chain_id: chain_id.to_string(),
+        }])
+        .expect("couldn't send method params via JSON");
+
+        self.provider_and_listeners
+            .borrow()
+            .provider
+            .request_wrapped(RequestArguments {
+                method: String::from("wallet_switchEthereumChain"),
+                params: js_sys::Array::from(&js_params),
+            })
+            .await
+    }
+}
+
+#[derive(serde::Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ChainId {
+    pub chain_id: String,
 }
 
 /// Event data sent from the JavaScript side to our callback.
@@ -179,7 +202,7 @@
                 ..
             }) => {
                 let js_params =
                     js_sys::Array::from(&JsValue::from_serde(&params).expect("couldn't send method params via JSON"));
                 let copy = self.provider_and_listeners.borrow().provider.clone();
                 Box::pin(async move {
                     copy.request_wrapped(RequestArguments {
@@ -263,8 +286,8 @@
         }
 
         let parsed_value = resp
             .map(|res| res.into_serde())
             .map_err(|err| err.into_serde::<RPCErrorExtra>());
         match parsed_value {
             Ok(Ok(res)) => Ok(res),
             Err(Ok(err)) => Err(Error::Rpc(err.into())),
@@ -340,14 +363,14 @@
 
     fn json_to_js(json: &str) -> JsValue {
         let json_value = serde_json::from_str::<serde_json::Value>(json).unwrap();
         let js_value = JsValue::from_serde(&json_value).unwrap();
         js_value
     }
 
     #[wasm_bindgen_test]
     fn parses_valid_response_correctly() {
         let value = serde_json::from_str::<serde_json::Value>(r#"[1, false, null, "string"]"#).unwrap();
         let response = Ok(JsValue::from_serde(&value).unwrap());
         let expected_result = Ok(value);
         assert_eq!(Provider::parse_response(response), expected_result);