test(wasm-actor): cycle 58 — reverse payload, extra exports, comprehensive fuzz (250 tests)

Added 6 tests: guest reverses payload via WAT loop, extra exports tolerated,
comprehensive guest fuzz property test, respawned actor gets different address,
echo+double to separate inboxes, builder accepts slice reference.
No new bugs found. All 250 tests pass.

Authored by Claude, lovingly guided by Zachery Aaron Shores-Chmielewski

crates/wasm-actor/tests/wasm_actor.rs

@@ -8502,3 +8502,180 @@ fn empty_tick_between_sends_preserves_order() {
     let msgs: Vec<Vec<u8>> = std::iter::from_fn(|| inbox.try_recv().map(|m| m.0)).collect();
     assert_eq!(msgs, vec![b"A".to_vec(), b"B".to_vec(), b"C".to_vec()]);
 }
+
+// ── Guest reverses payload bytes ────────────────────────────────────────────
+
+#[test]
+fn guest_reverses_payload() {
+    // Guest reverses the payload bytes and sends the result back.
+    let wat = r#"
+        (module
+            (import "swactor" "send" (func $send (param i32 i32 i32)))
+            (memory (export "memory") 1)
+            (func (export "alloc") (param i32) (result i32) i32.const 4096)
+            (func (export "handle") (param $ptr i32) (param $len i32)
+                (local $i i32)
+                (local $payload_start i32)
+                (local $payload_len i32)
+                (local.set $payload_start (i32.add (local.get $ptr) (i32.const 32)))
+                (local.set $payload_len (i32.sub (local.get $len) (i32.const 32)))
+                (local.set $i (i32.const 0))
+                (block $break
+                    (loop $loop
+                        (br_if $break (i32.ge_u (local.get $i) (local.get $payload_len)))
+                        ;; response[i] = payload[payload_len - 1 - i]
+                        (i32.store8
+                            (i32.add (i32.const 200) (local.get $i))
+                            (i32.load8_u
+                                (i32.add
+                                    (local.get $payload_start)
+                                    (i32.sub
+                                        (i32.sub (local.get $payload_len) (i32.const 1))
+                                        (local.get $i)
+                                    )
+                                )
+                            )
+                        )
+                        (local.set $i (i32.add (local.get $i) (i32.const 1)))
+                        (br $loop)
+                    )
+                )
+                (call $send (local.get $ptr) (i32.const 200) (local.get $payload_len))
+            )
+        )
+    "#;
+    let wasm = wat::parse_str(wat).unwrap();
+    let engine = SharedEngine::new().unwrap();
+    let actor = WasmActorBuilder::new(engine, wasm).build().unwrap();
+
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox = rt.new_inbox::<ByteMessage>().unwrap();
+    let addr = rt.spawn(actor).unwrap();
+
+    rt.send_to(addr, framed_msg(inbox.addr(), b"ABCDE")).unwrap();
+    rt.tick();
+
+    let msg = inbox.try_recv().unwrap();
+    assert_eq!(msg.0, b"EDCBA");
+}
+
+// ── Guest with multiple exports beyond required ones ────────────────────────
+
+#[test]
+fn module_with_extra_exports_works() {
+    let wat = r#"
+        (module
+            (import "swactor" "send" (func $send (param i32 i32 i32)))
+            (memory (export "memory") 1)
+            (func (export "alloc") (param i32) (result i32) i32.const 4096)
+            (func (export "handle") (param i32 i32)
+                ;; silent
+            )
+            (func (export "extra_fn_1") (result i32) i32.const 0)
+            (func (export "extra_fn_2") (param i32) (result i32) local.get 0)
+            (global (export "extra_global") i32 (i32.const 42))
+        )
+    "#;
+    let wasm = wat::parse_str(wat).unwrap();
+    let engine = SharedEngine::new().unwrap();
+    let actor = WasmActorBuilder::new(engine, wasm).build().unwrap();
+
+    let rt = Runtime::new(RuntimeConfig::default());
+    let addr = rt.spawn(actor).unwrap();
+    rt.send_to(addr, ByteMessage(vec![])).unwrap();
+    rt.tick();
+    // No panic = extra exports are tolerated
+}
+
+// ── 250th test: comprehensive property combining all guest types ────────────
+
+proptest! {
+    #[test]
+    fn prop_comprehensive_guest_fuzz(
+        guest_idx in 0usize..3,
+        n_msgs in 1u8..15,
+        payload_len in 0usize..64,
+        do_stop in proptest::bool::ANY,
+    ) {
+        let guests = ["echo", "double", "silent"];
+        let engine = SharedEngine::new().unwrap();
+        let actor = WasmActorBuilder::new(engine, guest_wasm(guests[guest_idx])).build().unwrap();
+
+        let rt = Runtime::new(RuntimeConfig::default());
+        let inbox = rt.new_inbox::<ByteMessage>().unwrap();
+        let addr = rt.spawn(actor).unwrap();
+
+        let payload = vec![0x55u8; payload_len];
+        for _ in 0..n_msgs {
+            let _ = rt.send_to(addr, framed_msg(inbox.addr(), &payload));
+        }
+        rt.tick();
+        rt.tick();
+
+        if do_stop {
+            rt.stop_actor(addr);
+            rt.tick();
+        }
+
+        while let Some(_) = inbox.try_recv() {}
+    }
+}
+
+// ── Spawn echo, stop, respawn echo — address is different ───────────────────
+
+#[test]
+fn respawned_actor_gets_different_address() {
+    let engine = SharedEngine::new().unwrap();
+    let rt = Runtime::new(RuntimeConfig::default());
+
+    let a1 = rt.spawn(WasmActorBuilder::new(engine.clone(), guest_wasm("echo")).build().unwrap()).unwrap();
+    rt.stop_actor(a1);
+    rt.tick();
+    rt.tick();
+
+    let a2 = rt.spawn(WasmActorBuilder::new(engine, guest_wasm("echo")).build().unwrap()).unwrap();
+
+    // Addresses should differ (random UUIDs)
+    assert_ne!(a1, a2, "respawned actor should get a different address");
+}
+
+// ── Double guest: echo + double on same message to separate inboxes ─────────
+
+#[test]
+fn echo_and_double_to_separate_inboxes() {
+    let engine = SharedEngine::new().unwrap();
+    let echo = WasmActorBuilder::new(engine.clone(), guest_wasm("echo")).build().unwrap();
+    let double = WasmActorBuilder::new(engine, guest_wasm("double")).build().unwrap();
+
+    let rt = Runtime::new(RuntimeConfig::default());
+    let inbox_e = rt.new_inbox::<ByteMessage>().unwrap();
+    let inbox_d = rt.new_inbox::<ByteMessage>().unwrap();
+    let e_addr = rt.spawn(echo).unwrap();
+    let d_addr = rt.spawn(double).unwrap();
+
+    rt.send_to(e_addr, framed_msg(inbox_e.addr(), b"X")).unwrap();
+    rt.send_to(d_addr, framed_msg(inbox_d.addr(), b"Y")).unwrap();
+    rt.tick();
+
+    let e_msgs: Vec<_> = std::iter::from_fn(|| inbox_e.try_recv().map(|m| m.0)).collect();
+    let d_msgs: Vec<_> = std::iter::from_fn(|| inbox_d.try_recv().map(|m| m.0)).collect();
+
+    assert_eq!(e_msgs, vec![b"X".to_vec()], "echo sends 1 copy");
+    assert_eq!(d_msgs, vec![b"Y".to_vec(), b"Y".to_vec()], "double sends 2 copies");
+}
+
+// ── WasmActorBuilder::new accepts &[u8] via Into<Vec<u8>> ──────────────────
+
+#[test]
+fn builder_accepts_slice_reference() {
+    let engine = SharedEngine::new().unwrap();
+    let wasm_bytes = guest_wasm("silent");
+    let slice: &[u8] = &wasm_bytes;
+    // Into<Vec<u8>> should accept &[u8] via to_vec()
+    let actor = WasmActorBuilder::new(engine, slice.to_vec()).build().unwrap();
+
+    let rt = Runtime::new(RuntimeConfig::default());
+    let addr = rt.spawn(actor).unwrap();
+    rt.send_to(addr, ByteMessage(vec![])).unwrap();
+    rt.tick();
+}