WIP

yarn-project/acir-simulator/src/acvm/deserialize.ts

@@ -58,15 +58,6 @@ export function frToBoolean(fr: Fr): boolean {
   return buf[buf.length - 1] !== 0;
 }
 
-/**
- * Converts a field to a function selector.
- * @param fr - The field to convert.
- * @returns The function selector.
- */
-export function frToSelector(fr: Fr): FunctionSelector {
-  return FunctionSelector.fromBuffer(fr.toBuffer().slice(-4));
-}
-
 /**
  * Extracts the return fields of a given partial witness.
  * @param acir - The bytecode of the function.

yarn-project/acir-simulator/src/client/private_execution.ts

@@ -13,7 +13,7 @@ import { createDebugLogger } from '@aztec/foundation/log';
 import { to2Fields } from '@aztec/foundation/serialize';
 import { FunctionL2Logs, NotePreimage, NoteSpendingInfo } from '@aztec/types';
 
-import { extractPrivateCircuitPublicInputs, frToAztecAddress, frToSelector } from '../acvm/deserialize.js';
+import { extractPrivateCircuitPublicInputs, frToAztecAddress } from '../acvm/deserialize.js';
 import {
   ZERO_ACVM_FIELD,
   acvm,
@@ -132,7 +132,7 @@ export class PrivateFunctionExecution {
 
           const childExecutionResult = await this.callPrivateFunction(
             frToAztecAddress(contractAddress),
-            frToSelector(functionSelector),
+            FunctionSelector.fromField(functionSelector),
             fromACVMField(acvmArgsHash),
             this.callContext,
             this.curve,
@@ -157,7 +157,7 @@ export class PrivateFunctionExecution {
         enqueuePublicFunctionCall: async ([acvmContractAddress], [acvmFunctionSelector], [acvmArgsHash]) => {
           const enqueuedRequest = await this.enqueuePublicFunctionCall(
             frToAztecAddress(fromACVMField(acvmContractAddress)),
-            frToSelector(fromACVMField(acvmFunctionSelector)),
+            FunctionSelector.fromField(fromACVMField(acvmFunctionSelector)),
             this.context.packedArgsCache.unpack(fromACVMField(acvmArgsHash)),
             this.callContext,
           );

yarn-project/acir-simulator/src/public/executor.ts

@@ -18,7 +18,6 @@ import {
   convertACVMFieldToBuffer,
   extractPublicCircuitPublicInputs,
   frToAztecAddress,
-  frToSelector,
   fromACVMField,
   toACVMField,
   toACVMWitness,
@@ -118,7 +117,7 @@ export class PublicExecutor {
         this.log(`Public function call: addr=${address} selector=${functionSelector} args=${args.join(',')}`);
         const childExecutionResult = await this.callPublicFunction(
           frToAztecAddress(fromACVMField(address)),
-          frToSelector(fromACVMField(functionSelector)),
+          FunctionSelector.fromField(fromACVMField(functionSelector)),
           args,
           execution.callContext,
           globalVariables,

yarn-project/aztec.js/src/account/entrypoint/entrypoint_payload.ts

@@ -52,7 +52,7 @@ export async function buildPayload(
       // eslint-disable-next-line camelcase
       flattened_args_hashes: packedArguments.map(args => args.hash),
       // eslint-disable-next-line camelcase
-      flattened_selectors: calls.map(call => Fr.fromBuffer(call.functionData.functionSelector.toBuffer())),
+      flattened_selectors: calls.map(call => call.functionData.functionSelector.toField()),
       // eslint-disable-next-line camelcase
       flattened_targets: calls.map(call => call.to.toField()),
       nonce,

yarn-project/canary/src/uniswap_trade_on_l1_from_l2.test.ts

@@ -264,7 +264,7 @@ describe('uniswap_trade_on_l1_from_l2', () => {
     // 4. Send L2 to L1 message to withdraw funds and another message to swap assets.
     logger('Send L2 tx to withdraw WETH to uniswap portal and send message to swap assets on L1');
     // recipient is the uniswap portal
-    const selector = Fr.fromBuffer(wethL2Contract.methods.withdraw.selector.toBuffer());
+    const selector = wethL2Contract.methods.withdraw.selector.toField();
     const minimumOutputAmount = 0n;
 
     const withdrawTx = uniswapL2Contract.methods

yarn-project/circuits.js/src/cbind/types.ts

@@ -28,7 +28,6 @@ export {
   G1AffineElement,
   NewContractData,
   FunctionData,
-  FunctionSelector,
   OptionallyRevealedData,
   PublicDataRead,
   PublicDataUpdateRequest,
@@ -53,6 +52,7 @@ export {
   Coordinate,
   GlobalVariables,
 } from '../structs/index.js';
+export { FunctionSelector } from '@aztec/foundation/abi';
 
 /**
  * A pointer to a Prover object in WebAssembly memory.

yarn-project/circuits.js/src/contract/contract_deployment_info.ts

@@ -5,17 +5,9 @@ import {
   computeVarArgsHash,
   hashConstructor,
 } from '@aztec/circuits.js/abis';
-import { ContractAbi, encodeArguments } from '@aztec/foundation/abi';
+import { ContractAbi, FunctionSelector, encodeArguments } from '@aztec/foundation/abi';
 
-import {
-  CircuitsWasm,
-  CompleteAddress,
-  DeploymentInfo,
-  Fr,
-  FunctionData,
-  FunctionSelector,
-  PublicKey,
-} from '../index.js';
+import { CircuitsWasm, CompleteAddress, DeploymentInfo, Fr, FunctionData, PublicKey } from '../index.js';
 import { generateFunctionLeaves, hashVKStr, isConstructor } from './contract_tree/contract_tree.js';
 
 /**

yarn-project/circuits.js/src/contract/contract_tree/contract_tree.ts

@@ -1,13 +1,6 @@
-import {
-  CircuitsWasm,
-  ContractFunctionDao,
-  Fr,
-  FunctionData,
-  FunctionLeafPreimage,
-  FunctionSelector,
-} from '@aztec/circuits.js';
+import { CircuitsWasm, ContractFunctionDao, Fr, FunctionData, FunctionLeafPreimage } from '@aztec/circuits.js';
 import { computeFunctionLeaf, hashVK } from '@aztec/circuits.js/abis';
-import { FunctionType } from '@aztec/foundation/abi';
+import { FunctionSelector, FunctionType } from '@aztec/foundation/abi';
 
 /**
  * Computes the hash of a hex-encoded string representation of a verification key (vk).

yarn-project/circuits.js/src/structs/index.ts

@@ -24,7 +24,6 @@ export * from './tx_request.js';
 export * from './tx_context.js';
 export * from './verification_key.js';
 export * from './function_leaf_preimage.js';
-export * from '../../../foundation/src/abi/function_selector.js';
 export * from './aggregation_object.js';
 export * from './membership_witness.js';
 export * from './read_request_membership_witness.js';
@@ -33,3 +32,4 @@ export * from '@aztec/foundation/eth-address';
 
 export * from '@aztec/foundation/fields';
 export * from '@aztec/foundation/aztec-address';
+export { FunctionSelector } from '@aztec/foundation/abi';

yarn-project/circuits.js/tsconfig.json

@@ -10,5 +10,5 @@
       "path": "../foundation"
     }
   ],
-  "include": ["src", "../foundation/src/abi/function_selector.ts"]
+  "include": ["src"]
 }

yarn-project/end-to-end/src/e2e_pending_commitments_contract.test.ts

@@ -143,8 +143,8 @@ describe('e2e_pending_commitments_contract', () => {
       .test_insert2_then_get2_then_nullify1_all_in_nested_calls(
         mintAmount,
         owner,
-        Fr.fromBuffer(deployedContract.methods.insert_note.selector),
-        Fr.fromBuffer(deployedContract.methods.get_then_nullify_note.selector),
+        deployedContract.methods.insert_note.selector.toField(),
+        deployedContract.methods.get_then_nullify_note.selector.toField(),
       )
       .send({ origin: owner });
 

yarn-project/end-to-end/src/uniswap_trade_on_l1_from_l2.test.ts

@@ -189,7 +189,7 @@ describe('uniswap_trade_on_l1_from_l2', () => {
 
     // 4. Send L2 to L1 message to withdraw funds and another message to swap assets.
     logger('Send L2 tx to withdraw WETH to uniswap portal and send message to swap assets on L1');
-    const selector = Fr.fromBuffer(wethCrossChainHarness.l2Contract.methods.withdraw.selector);
+    const selector = wethCrossChainHarness.l2Contract.methods.withdraw.selector.toField();
     const minimumOutputAmount = 0;
 
     const withdrawTx = uniswapL2Contract.methods

yarn-project/noir-compiler/src/contract-interface-gen/noir.ts

@@ -31,7 +31,7 @@ function isPrivateCall(functionType: FunctionType) {
 function generateCallStatement(selector: FunctionSelector, functionType: FunctionType) {
   const callMethod = isPrivateCall(functionType) ? 'call_private_function' : 'call_public_function';
   return `
-    context.${callMethod}(self.address, ${selector.toString()}, serialised_args)`;
+    context.${callMethod}(self.address, 0x${selector.toString()}, serialised_args)`;
 }
 
 /**