chore: rename note discovery to message discovery (#12755)

It's not just notes, so updating some of the terms ahead of known future
improvements.

Author: nventuro

noir-projects/aztec-nr/aztec/src/discovery/mod.nr

@@ -18,7 +18,7 @@ pub global MAX_NOTE_PACKED_LEN: u32 =
 pub struct NoteHashAndNullifier {
     /// The result of NoteHash::compute_note_hash
     pub note_hash: Field,
-    /// The result of NoteHash::compute_nullifier_unconstrained (since all of note discovery is unconstrained)
+    /// The result of NoteHash::compute_nullifier_unconstrained (since all of message discovery is unconstrained)
     pub inner_nullifier: Field,
 }
 
@@ -59,16 +59,17 @@ pub struct NoteHashAndNullifier {
 /// ```
 type ComputeNoteHashAndNullifier<Env> = unconstrained fn[Env](/* packed_note_content */BoundedVec<Field, MAX_NOTE_PACKED_LEN>, /* storage_slot */ Field, /* note_type_id */ Field, /* contract_address */ AztecAddress, /* nonce */ Field) -> Option<NoteHashAndNullifier>;
 
-/// Performs the note discovery process, in which private and public logs are downloaded and inspected to find private
-/// notes, partial notes, and their completion. This is the mechanism via which PXE learns of new notes.
+/// Performs the message discovery process, in which private are downloaded and inspected to find new private notes,
+/// partial notes and events, etc., and pending partial notes are processed to search for their completion logs.
+/// This is the mechanism via which a contract updates its knowldge of its private state.
 ///
-/// Receives the address of the contract on which discovery is performed (i.e. the contract that emitted the notes)
-/// along with its `compute_note_hash_and_nullifier` function.
-pub unconstrained fn discover_new_notes<Env>(
+/// Receives the address of the contract on which discovery is performed along with its
+/// `compute_note_hash_and_nullifier` function.
+pub unconstrained fn discover_new_messages<Env>(
     contract_address: AztecAddress,
     compute_note_hash_and_nullifier: ComputeNoteHashAndNullifier<Env>,
 ) {
-    debug_log("Performing note discovery");
+    debug_log("Performing message discovery");
 
     private_logs::fetch_and_process_private_tagged_logs(
         contract_address,

noir-projects/aztec-nr/aztec/src/discovery/nonce_discovery.nr

@@ -35,7 +35,7 @@ pub unconstrained fn attempt_note_nonce_discovery<Env>(
     let discovered_notes = &mut BoundedVec::new();
 
     debug_log_format(
-        "Attempting note discovery on {0} potential notes on contract {1} for storage slot {2}",
+        "Attempting nonce discovery on {0} potential notes on contract {1} for storage slot {2}",
         [unique_note_hashes_in_tx.len() as Field, contract_address.to_field(), storage_slot],
     );
 

noir-projects/aztec-nr/aztec/src/discovery/partial_notes.nr

@@ -5,7 +5,7 @@ use crate::{
         nonce_discovery::{attempt_note_nonce_discovery, DiscoveredNoteInfo},
         private_logs::MAX_PARTIAL_NOTE_PRIVATE_PACKED_LEN,
     },
-    oracle::note_discovery::{deliver_note, get_log_by_tag},
+    oracle::message_discovery::{deliver_note, get_log_by_tag},
     utils::array,
 };
 
@@ -72,8 +72,8 @@ pub unconstrained fn fetch_and_process_public_partial_note_completion_logs<Env>(
                 );
                 *i += 1 as u32;
                 // Note that we're not removing the pending partial note from the PXE DB, so we will continue searching
-                // for this tagged log when performing note discovery in the future until we either find it or the entry
-                // is somehow removed from the PXE DB.
+                // for this tagged log when performing message discovery in the future until we either find it or the
+                // entry is somehow removed from the PXE DB.
             } else {
                 debug_log_format(
                     "Completion log found for partial note with tag {}",

noir-projects/aztec-nr/aztec/src/discovery/private_logs.nr

@@ -2,7 +2,7 @@ use std::static_assert;
 
 use crate::{
     capsules::CapsuleArray,
-    oracle::note_discovery::{deliver_note, sync_notes},
+    oracle::message_discovery::{deliver_note, sync_notes},
     utils::array,
 };
 

noir-projects/aztec-nr/aztec/src/encrypted_logs/log_assembly_strategies/default_aes128/note/encryption.nr

@@ -46,7 +46,7 @@ pub global PRIVATE_LOG_PLAINTEXT_SIZE_IN_FIELDS: u32 = PRIVATE_LOG_PLAINTEXT_SIZ
 /// The resulting log has the following format:
 /// ```text
 /// [
-///   tag: Field,                    // Tag for note discovery, derived from sender/recipient
+///   tag: Field,                    // Tag for message discovery, derived from sender/recipient
 ///   epk_x: Field,                  // X coordinate of ephemeral public key
 ///   log_bytes: [Field],            // Encrypted data converted from bytes to fields, containing:
 ///     [

noir-projects/aztec-nr/aztec/src/macros/functions/utils.nr

@@ -98,10 +98,10 @@ pub(crate) comptime fn transform_private(f: FunctionDefinition) -> Quoted {
         quote {}
     };
 
-    // All private functions perform note discovery, since they may need to access notes. This is slightly inefficient
-    // and could be improved by only doing it once we actually attempt to read any.
-    let note_discovery_call = if NOTES.len() > 0 {
-        create_note_discovery_call()
+    // All private functions perform message discovery, since they may need to access notes. This is slightly
+    // inefficient and could be improved by only doing it once we actually attempt to read any.
+    let message_discovery_call = if NOTES.len() > 0 {
+        create_message_discovery_call()
     } else {
         quote {}
     };
@@ -157,7 +157,7 @@ pub(crate) comptime fn transform_private(f: FunctionDefinition) -> Quoted {
         $internal_check
         $view_check
         $storage_init
-        $note_discovery_call
+        $message_discovery_call
     };
 
     let to_append = quote {
@@ -325,18 +325,19 @@ pub(crate) comptime fn transform_top_level_unconstrained(f: FunctionDefinition)
         quote {}
     };
 
-    // All unconstrained functions perform note discovery, since they may need to access notes. This is slightly
-    // inefficient and could be improved by only doing it once we actually attempt to read any.
-    let note_discovery_call = if NOTES.len() > 0 {
-        create_note_discovery_call()
+    // All unconstrained functions perform message discovery, since they may need to access private notes that would be
+    // found during this process. This is slightly inefficient and could be improved by only doing it once we actually
+    // attempt to read any.
+    let message_discovery_call = if NOTES.len() > 0 {
+        create_message_discovery_call()
     } else {
         quote {}
     };
 
     let to_prepend = quote {
         $context_creation
         $storage_init
-        $note_discovery_call
+        $message_discovery_call
     };
     let body = f.body().as_block().unwrap();
     let modified_body = modify_fn_body(body, to_prepend, quote {});
@@ -380,14 +381,14 @@ comptime fn create_init_check(f: FunctionDefinition) -> Quoted {
         .quoted_contents()
 }
 
-/// Injects a call to `aztec::discovery::discover_new_notes`, causing for new notes to be added to PXE and made
+/// Injects a call to `aztec::discovery::discover_new_messages`, causing for new notes to be added to PXE and made
 /// available for the current execution.
-pub(crate) comptime fn create_note_discovery_call() -> Quoted {
+pub(crate) comptime fn create_message_discovery_call() -> Quoted {
     quote {
-        /// Safety: note discovery returns nothing and is performed solely for its side-effects. It is therefore always
-        /// safe to call.
+        /// Safety: message discovery returns nothing and is performed solely for its side-effects. It is therefore
+        /// always safe to call.
         unsafe {
-            dep::aztec::discovery::discover_new_notes(
+            dep::aztec::discovery::discover_new_messages(
                 context.this_address(),
                 _compute_note_hash_and_nullifier,
             );

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

@@ -7,7 +7,7 @@ pub mod events;
 
 use functions::{
     stub_registry,
-    utils::{create_note_discovery_call, find_and_transform_top_level_unconstrained_fns},
+    utils::{create_message_discovery_call, find_and_transform_top_level_unconstrained_fns},
 };
 use notes::{generate_note_export, NOTES};
 use storage::STORAGE_LAYOUT_NAME;
@@ -189,7 +189,7 @@ comptime fn generate_contract_library_method_compute_note_hash_and_nullifier() -
 
                         let note_hash = $compute_note_hash(note, storage_slot);
 
-                        // The note discovery process finds settled notes, that is, notes that were created in prior
+                        // The message discovery process finds settled notes, that is, notes that were created in prior
                         // transactions and are therefore already part of the note hash tree. We therefore compute the
                         // nullification note hash by treating the note as a settled note with the provided nonce.
                         let note_hash_for_nullify = aztec::note::utils::compute_note_hash_for_nullify(
@@ -221,8 +221,8 @@ comptime fn generate_contract_library_method_compute_note_hash_and_nullifier() -
             /// tree with `nonce`.
             ///
             /// The signature of this function notably matches the `aztec::discovery::ComputeNoteHashAndNullifier` type,
-            /// and so it can be used to call functions from that module such as `discover_new_notes`, `do_process_log`
-            /// and `attempt_note_discovery`.
+            /// and so it can be used to call functions from that module such as `discover_new_messages`, 
+            /// `do_process_log` and `attempt_note_discovery`.
             ///
             /// This function is automatically injected by the `#[aztec]` macro.
             #[contract_library_method]
@@ -263,7 +263,7 @@ comptime fn generate_contract_library_method_compute_note_hash_and_nullifier() -
 
 comptime fn generate_process_log() -> Quoted {
     // This mandatory function processes a log emitted by the contract. This is currently used to process private logs
-    // and perform note discovery of either private notes or partial notes.
+    // and perform message discovery, resulting in new private notes, partial notes and events.
     // The bulk of the work of this function is done by aztec::discovery::do_process_log, so all we need to do is call
     // that function.
 
@@ -279,9 +279,9 @@ comptime fn generate_process_log() -> Quoted {
                 first_nullifier_in_tx: Field,
                 recipient: aztec::protocol_types::address::AztecAddress,
             ) {
-                // Because this unconstrained function is injected after the contract is processed by the macros, it'll not
-                // be modified by the macros that alter unconstrained functions. As such, we need to manually inject the
-                // unconstrained execution context since it will not be available otherwise.
+                // Because this unconstrained function is injected after the contract is processed by the macros, it'll
+                // not be modified by the macros that alter unconstrained functions. As such, we need to manually inject
+                // the unconstrained execution context since it will not be available otherwise.
                 let context = dep::aztec::context::unconstrained_context::UnconstrainedContext::new();
 
                 // TODO(#10727): allow other contracts to process logs and deliver notes
@@ -327,15 +327,15 @@ comptime fn generate_note_exports() -> Quoted {
 }
 
 comptime fn generate_sync_notes() -> Quoted {
-    let note_discovery_call = create_note_discovery_call();
+    let message_discovery_call = create_message_discovery_call();
     quote {
         unconstrained fn sync_notes() {
             // Because this unconstrained function is injected after the contract is processed by the macros, it'll not
             // be modified by the macros that alter unconstrained functions. As such, we need to manually inject the
             // unconstrained execution context since it will not be available otherwise.
             let context = dep::aztec::context::unconstrained_context::UnconstrainedContext::new();
 
-            $note_discovery_call
+            $message_discovery_call
         }
     }
 }

noir-projects/aztec-nr/aztec/src/oracle/note_discovery.nr noir-projects/aztec-nr/aztec/src/oracle/message_discovery.nr

@@ -17,7 +17,7 @@ pub mod get_membership_witness;
 pub mod keys;
 pub mod key_validation_request;
 pub mod logs;
-pub mod note_discovery;
+pub mod message_discovery;
 pub mod notes;
 pub mod random;
 pub mod shared_secret;

noir-projects/aztec-nr/aztec/src/oracle/mod.nr

@@ -1,8 +1,8 @@
 import { MAX_NOTE_HASHES_PER_TX, PUBLIC_LOG_DATA_SIZE_IN_FIELDS } from '@aztec/constants';
 import { Fr } from '@aztec/foundation/fields';
 
-// TypeScript representation of the Noir aztec::oracle::note_discovery::LogWithTxData struct. This is used as a response
-// for PXE's custom getLogByTag oracle.
+// TypeScript representation of the Noir aztec::oracle::message_discovery::LogWithTxData struct. This is used as a
+// response for PXE's custom getLogByTag oracle.
 export class LogWithTxData {
   constructor(
     public logContent: Fr[],