Add a test to catch excessive memory growth

soroban-env-host/src/test/hostile.rs

@@ -116,3 +116,37 @@ fn hostile_objs_traps() -> Result<(), HostError> {
     ));
     Ok(())
 }
+
+use soroban_synth_wasm::{Arity, ModEmitter, Operand};
+
+fn wasm_module_with_mem_grow(n_pages: usize) -> Vec<u8> {
+    let mut fe = ModEmitter::new().func(Arity(0), 0);
+    fe.push(Operand::Const32(n_pages as i32));
+    fe.memory_grow();
+    // need to drop the return value on the stack because it's an i32
+    // and the function needs an i64 return value.
+    fe.drop();
+    fe.push(Symbol::try_from_small_str("pass").unwrap());
+    fe.finish_and_export("test").finish()
+}
+
+#[test]
+fn excessive_memory_growth() -> Result<(), HostError> {
+    let wasm = wasm_module_with_mem_grow(32);
+    let host = Host::test_host_with_recording_footprint();
+    let contract_id_obj = host.register_test_contract_wasm(wasm.as_slice());
+    host.set_diagnostic_level(crate::DiagnosticLevel::Debug)?;
+
+    // This one should just run out of memory
+    let res = host.call(
+        contract_id_obj,
+        Symbol::try_from_small_str("test")?,
+        host.add_host_object(HostVec::new())?,
+    );
+
+    assert!(HostError::result_matches_err(
+        res,
+        (ScErrorType::Budget, ScErrorCode::ExceededLimit)
+    ));
+    Ok(())
+}