feat: add compile-time size check for events and error code links

docs/netlify.toml

@@ -774,8 +774,13 @@
     from = "/errors/3"
     to = "/aztec-nr-api/nightly/noir_aztec/messages/msg_type/index.html"
 
-# Example (uncomment and modify when adding error codes):
-# [[redirects]]
-#     from = "/errors/4"
-#     to = "/developers/docs/aztec-nr/framework-description/functions/how_to_define_functions"
+[[redirects]]
+    # Aztec-nr: note packed length exceeds MAX_NOTE_PACKED_LEN
+    from = "/errors/4"
+    to = "/aztec-nr-api/nightly/noir_aztec/macros/notes/fn.note.html"
+
+[[redirects]]
+    # Aztec-nr: event serialized length exceeds MAX_EVENT_SERIALIZED_LEN
+    from = "/errors/5"
+    to = "/aztec-nr-api/nightly/noir_aztec/macros/events/fn.event.html"
 

noir-projects/aztec-nr/aztec/src/macros/events.nr

@@ -10,6 +10,9 @@ pub comptime mut global EVENT_SELECTORS: CHashMap<Field, Quoted> = CHashMap::new
 
 comptime fn generate_event_interface_and_get_selector(s: TypeDefinition) -> (Quoted, Field) {
     let name = s.name();
+    let typ = s.as_type();
+    let event_type_name: str<_> = f"{name}".as_quoted_str!();
+    let max_event_serialized_len = crate::messages::logs::event::MAX_EVENT_SERIALIZED_LEN;
 
     let event_selector = compute_struct_selector(s, quote { crate::event::EventSelector::from_signature });
 
@@ -23,6 +26,18 @@ comptime fn generate_event_interface_and_get_selector(s: TypeDefinition) -> (Quo
         quote {
         impl aztec::event::event_interface::EventInterface for $name {
             fn get_event_type_id() -> aztec::event::EventSelector {
+                // This static assertion ensures the event's serialized length doesn't exceed the maximum
+                // allowed size. While this check would ideally live in the Serialize trait implementation, we
+                // place it here since this function is always generated by our macros and the Serialize trait
+                // implementation is not.
+                //
+                // Note: We set the event type name and max serialized length as local variables because
+                // injecting them directly into the error message doesn't work.
+                let event_type_name = $event_type_name;
+                let max_event_serialized_len: u32 = $max_event_serialized_len;
+                let event_serialized_len = <$typ as aztec::protocol::traits::Serialize>::N;
+                std::static_assert(event_serialized_len <= $max_event_serialized_len, f"{event_type_name} has a serialized length of {event_serialized_len} fields, which exceeds the maximum allowed length of {max_event_serialized_len} fields. See https://docs.aztec.network/errors/5");
+
                 $from_field($event_selector)
             }
         }
@@ -42,6 +57,14 @@ comptime fn register_event_selector(event_selector: Field, event_name: Quoted) {
     EVENT_SELECTORS.insert(event_selector, event_name);
 }
 
+/// Generates the core event functionality for a struct, including the
+/// [`EventInterface`](crate::event::event_interface::EventInterface) implementation (which provides the event type
+/// id) and a [`Serialize`](crate::protocol::traits::Serialize) implementation if one is not already provided.
+///
+/// ## Requirements
+///
+/// The event struct must not exceed
+/// [`MAX_EVENT_SERIALIZED_LEN`](crate::messages::logs::event::MAX_EVENT_SERIALIZED_LEN) when serialized.
 pub comptime fn event(s: TypeDefinition) -> Quoted {
     let (event_interface_impl, event_selector) = generate_event_interface_and_get_selector(s);
     register_event_selector(event_selector, s.name());

noir-projects/aztec-nr/aztec/src/macros/notes.nr

@@ -48,8 +48,8 @@ comptime fn generate_note_type_impl(s: TypeDefinition, note_type_id: Field) -> Q
                 // directly into the error message doesn't work.
                 let note_type_name = $note_type_name;
                 let max_note_packed_len: u32 = $max_note_packed_len; // Casting to u32 to avoid the value to be printed in hex.
-                let note_packed_len = <$typ as Packable>::N;
-                std::static_assert(note_packed_len <= $max_note_packed_len, f"{note_type_name} has a packed length of {note_packed_len} fields, which exceeds the maximum allowed length of {max_note_packed_len} fields");
+                let note_packed_len = <$typ as aztec::protocol::traits::Packable>::N;
+                std::static_assert(note_packed_len <= $max_note_packed_len, f"{note_type_name} has a packed length of {note_packed_len} fields, which exceeds the maximum allowed length of {max_note_packed_len} fields. See https://docs.aztec.network/errors/4");
 
                 $note_type_id
             }

noir-projects/noir-contracts-comp-failures/contracts/invalid_event/Nargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "invalid_event"
+authors = [""]
+compiler_version = ">=0.25.0"
+type = "contract"
+
+[dependencies]
+aztec = { path = "../../../aztec-nr/aztec" }

noir-projects/noir-contracts-comp-failures/contracts/invalid_event/expected_error

@@ -0,0 +1 @@
+InvalidEvent has a serialized length of 11 fields, which exceeds the maximum allowed length of 10 fields. See https://docs.aztec.network/errors/5

noir-projects/noir-contracts-comp-failures/contracts/invalid_event/src/invalid_event.nr

@@ -0,0 +1,18 @@
+use aztec::{
+    macros::events::event,
+    messages::logs::event::MAX_EVENT_SERIALIZED_LEN,
+    protocol::{traits::Serialize, utils::writer::Writer},
+};
+
+#[event]
+pub struct InvalidEvent {}
+
+impl Serialize for InvalidEvent {
+    let N: u32 = MAX_EVENT_SERIALIZED_LEN + 1;
+
+    fn serialize(self) -> [Field; Self::N] {
+        std::mem::zeroed()
+    }
+
+    fn stream_serialize<let K: u32>(self, _writer: &mut Writer<K>) {}
+}

noir-projects/noir-contracts-comp-failures/contracts/invalid_event/src/main.nr

@@ -0,0 +1,15 @@
+use aztec::macros::aztec;
+
+mod invalid_event;
+
+#[aztec]
+pub contract InvalidEventContract {
+    use crate::invalid_event::InvalidEvent;
+    use aztec::{event::event_interface::EventInterface, macros::functions::external};
+
+    // We have here this function in order for the static_assert in `get_event_type_id` to get triggered.
+    #[external("private")]
+    fn trigger_event_check() {
+        let _ = InvalidEvent::get_event_type_id();
+    }
+}

noir-projects/noir-contracts-comp-failures/contracts/invalid_note/expected_error

@@ -1 +1 @@
-InvalidNote has a packed length of 9 fields, which exceeds the maximum allowed length of 8 fields
+InvalidNote has a packed length of 9 fields, which exceeds the maximum allowed length of 8 fields. See https://docs.aztec.network/errors/4