feat: support --no-panic-recovery flag to disable panic reinitialization (#835)

guybedford · web-flow · commit c86c38005ae2 · 2025-10-06T11:16:08.000-07:00
diff --git a/test/src/counter.rs b/test/src/counter.rs
@@ -11,6 +11,7 @@ use crate::SomeSharedData;
 #[durable_object]
 pub struct Counter {
     count: RefCell<usize>,
+    unstored_count: RefCell<usize>,
     state: State,
     initialized: RefCell<bool>,
     env: Env,
@@ -20,6 +21,7 @@ impl DurableObject for Counter {
     fn new(state: State, env: Env) -> Self {
         Self {
             count: RefCell::new(0),
+            unstored_count: RefCell::new(0),
             initialized: RefCell::new(false),
             state,
             env,
@@ -47,13 +49,15 @@ impl DurableObject for Counter {
                 .empty());
         }
 
+        *self.unstored_count.borrow_mut() += 1;
         *self.count.borrow_mut() += 10;
         let count = *self.count.borrow();
         self.state.storage().put("count", count).await?;
 
         Response::ok(format!(
-            "[durable_object]: self.count: {}, secret value: {}",
+            "[durable_object]: self.count: {}, self.unstored_count: {}, secret value: {}",
             self.count.borrow(),
+            self.unstored_count.borrow(),
             self.env.secret("SOME_SECRET")?
         ))
     }
diff --git a/test/tests/panic.spec.ts b/test/tests/panic.spec.ts
@@ -1,32 +1,33 @@
 import { describe, test, expect } from "vitest";
-import { mf } from "./mf";
+import { mf, mfUrl } from "./mf";
 
 describe("Panic Hook with WASM Reinitialization", () => {
   test("panic recovery tests", async () => {
     // basic panic recovery
     {
-      const panicResp = await mf.dispatchFetch("http://fake.host/test-panic");
+      await mf.dispatchFetch(`${mfUrl}durable/COUNTER`);
+      const resp = await mf.dispatchFetch(`${mfUrl}durable/COUNTER`);
+      expect(await resp.text()).toContain("unstored_count: 2");
+
+      const panicResp = await mf.dispatchFetch(`${mfUrl}test-panic`);
       expect(panicResp.status).toBe(500);
 
       const panicText = await panicResp.text();
       expect(panicText).toContain("Workers runtime canceled");
 
-      const normalResp = await mf.dispatchFetch("http://fake.host/durable/hello");
-      expect(normalResp.status).toBe(200);
-
-      const normalText = await normalResp.text();
-      expect(normalText).toContain("Hello from my-durable-object!");
+      const normalResp = await mf.dispatchFetch(`${mfUrl}durable/COUNTER`);
+      expect(await normalResp.text()).toContain("unstored_count: 1");
     }
 
     // multiple requests after panic all succeed
     {
-      const panicResp = await mf.dispatchFetch("http://fake.host/test-panic");
+      const panicResp = await mf.dispatchFetch(`${mfUrl}test-panic`);
       expect(panicResp.status).toBe(500);
 
       const requests = [
-        mf.dispatchFetch("http://fake.host/durable/hello"),
-        mf.dispatchFetch("http://fake.host/durable/hello"),
-        mf.dispatchFetch("http://fake.host/durable/hello"),
+        mf.dispatchFetch(`${mfUrl}durable/hello`),
+        mf.dispatchFetch(`${mfUrl}durable/hello`),
+        mf.dispatchFetch(`${mfUrl}durable/hello`),
       ];
 
       const responses = await Promise.all(requests);
@@ -41,9 +42,9 @@ describe("Panic Hook with WASM Reinitialization", () => {
     // simultaneous requests during panic handling
     {
       const simultaneousRequests = [
-        mf.dispatchFetch("http://fake.host/test-panic"), // This will panic
-        mf.dispatchFetch("http://fake.host/durable/hello"), // This should succeed after reinitialization
-        mf.dispatchFetch("http://fake.host/durable/hello"),
+        mf.dispatchFetch(`${mfUrl}test-panic`), // This will panic
+        mf.dispatchFetch(`${mfUrl}durable/hello`), // This should succeed after reinitialization
+        mf.dispatchFetch(`${mfUrl}durable/hello`),
       ];
 
       const responses = await Promise.all(simultaneousRequests);
@@ -64,12 +65,10 @@ describe("Panic Hook with WASM Reinitialization", () => {
     // worker continues to function normally after multiple panics
     {
       for (let cycle = 1; cycle <= 3; cycle++) {
-        const panicResp = await mf.dispatchFetch("http://fake.host/test-panic");
+        const panicResp = await mf.dispatchFetch(`${mfUrl}test-panic`);
         expect(panicResp.status).toBe(500);
 
-        const recoveryResp = await mf.dispatchFetch(
-          "http://fake.host/durable/hello"
-        );
+        const recoveryResp = await mf.dispatchFetch(`${mfUrl}durable/hello`);
         expect(recoveryResp.status).toBe(200);
       }
     }
diff --git a/worker-build/src/main.rs b/worker-build/src/main.rs
@@ -56,11 +56,15 @@ fn update_package_json() -> Result<()> {
 }
 
 pub fn main() -> Result<()> {
-    let first_arg = env::args().nth(1);
-    if matches!(first_arg.as_deref(), Some("--version") | Some("-v")) {
+    let args: Vec<_> = env::args().collect();
+    if matches!(
+        args.first().map(String::as_str),
+        Some("--version") | Some("-v")
+    ) {
         println!("{}", VERSION);
         return Ok(());
     }
+    let no_panic_recovery = args.iter().any(|a| a == "--no-panic-recovery");
 
     let out_path = output_path("");
     if out_path.exists() {
@@ -72,15 +76,21 @@ pub fn main() -> Result<()> {
 
     wasm_pack_build.init()?;
 
-    let module_target = wasm_pack_build.supports_target_module_and_reset_state()?
-        || env::var("CUSTOM_SHIM").is_ok();
+    let supports_reset_state = wasm_pack_build.supports_target_module_and_reset_state()?;
+    let module_target =
+        supports_reset_state && !no_panic_recovery && env::var("CUSTOM_SHIM").is_err();
     if module_target {
         wasm_pack_build
             .extra_args
             .push("--experimental-reset-state-function".to_string());
         wasm_pack_build.run()?;
     } else {
-        eprintln!("A newer version of wasm-bindgen is available. Update to use the latest workers-rs features.");
+        if supports_reset_state {
+            // Enable once we have DO bindings to offer an alternative
+            // eprintln!("Using CUSTOM_SHIM will be deprecated in a future release.");
+        } else {
+            eprintln!("A newer version of wasm-bindgen is available. Update to use the latest workers-rs features.");
+        }
         wasm_pack_build.target = Target::Bundler;
         wasm_pack_build.run()?;
     }
diff --git a/worker-build/src/wasm_pack/command/build.rs b/worker-build/src/wasm_pack/command/build.rs
@@ -176,6 +176,10 @@ pub struct BuildOptions {
     /// List of extra options to pass to `cargo build`
     pub extra_options: Vec<String>,
 
+    #[clap(long, hide = true)]
+    /// Pass-through for --no-panic-recovery
+    pub no_panic_recovery: bool,
+
     #[deprecated(note = "runtime-detected")]
     #[allow(dead_code)]
     #[clap(long = "weak-refs", hide = true)]
