fix(sdk): normalize scale in warp check for config vs on-chain comparison (#8615)

Author: Xaroz

.changeset/quiet-rivers-flow.md

@@ -0,0 +1,5 @@
+---
+'@hyperlane-xyz/sdk': patch
+---
+
+Normalized scale values in warp route check so plain numbers from config and {numerator, denominator} objects from on-chain reader compare equal during diff.

typescript/sdk/src/token/configUtils.test.ts

@@ -85,6 +85,7 @@ describe('configUtils', () => {
               },
             ],
           },
+          scale: { numerator: 1n, denominator: 1n },
         },
       },
       {
@@ -109,6 +110,7 @@ describe('configUtils', () => {
               address: ADDRESS,
             },
           },
+          scale: { numerator: 1n, denominator: 1n },
         },
       },
       {
@@ -131,6 +133,7 @@ describe('configUtils', () => {
             address: ADDRESS,
             owner: ADDRESS,
           },
+          scale: { numerator: 1n, denominator: 1n },
         },
       },
       {
@@ -182,6 +185,7 @@ describe('configUtils', () => {
             owner: 'milk169dcaz397j75tjfpl6ykm23dfrv39dqd58lsag',
             type: 'native',
           },
+          scale: { numerator: 1n, denominator: 1n },
         },
         input: {
           bsc: {
@@ -242,6 +246,44 @@ describe('configUtils', () => {
       });
     }
 
+    it('normalizes plain number scale to {numerator, denominator} bigint', () => {
+      const transformedObj = transformConfigToCheck({
+        type: TokenType.collateral,
+        token: ADDRESS,
+        scale: 1000000000000,
+      } as any);
+
+      expect(transformedObj.scale).to.eql({
+        numerator: 1000000000000n,
+        denominator: 1n,
+      });
+    });
+
+    it('normalizes {number, number} scale to {bigint, bigint}', () => {
+      const transformedObj = transformConfigToCheck({
+        type: TokenType.collateral,
+        token: ADDRESS,
+        scale: { numerator: 1, denominator: 1000000000000 },
+      } as any);
+
+      expect(transformedObj.scale).to.eql({
+        numerator: 1n,
+        denominator: 1000000000000n,
+      });
+    });
+
+    it('normalizes undefined scale to identity {1n, 1n}', () => {
+      const transformedObj = transformConfigToCheck({
+        type: TokenType.collateral,
+        token: ADDRESS,
+      } as any);
+
+      expect(transformedObj.scale).to.eql({
+        numerator: 1n,
+        denominator: 1n,
+      });
+    });
+
     it('normalizes LinearFee maxFee/halfAmount so equivalent bps configs compare equal', () => {
       const transformedObj = transformConfigToCheck({
         type: TokenType.collateral,
@@ -259,6 +301,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.LinearFee,
           owner: ADDRESS,
@@ -286,6 +329,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.OffchainQuotedLinearFee,
           owner: ADDRESS,
@@ -322,6 +366,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.RoutingFee,
           owner: ADDRESS,
@@ -373,6 +418,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.CrossCollateralRoutingFee,
           owner: ADDRESS,
@@ -419,6 +465,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.CrossCollateralRoutingFee,
           owner: ADDRESS,
@@ -458,6 +505,7 @@ describe('configUtils', () => {
       expect(transformedObj).to.eql({
         type: TokenType.collateral,
         token: ADDRESS,
+        scale: { numerator: 1n, denominator: 1n },
         tokenFee: {
           type: TokenFeeType.RoutingFee,
           owner: ADDRESS,

typescript/sdk/src/token/configUtils.ts

@@ -35,6 +35,7 @@ import {
   resolveRouterMapConfig,
 } from '../router/types.js';
 import { ChainMap } from '../types.js';
+import { normalizeScale } from '../utils/decimals.js';
 import { WarpCoreConfig } from '../warp/types.js';
 
 import { EvmWarpRouteReader } from './EvmWarpRouteReader.js';
@@ -720,6 +721,10 @@ export function transformConfigToCheck(
     );
   }
 
+  // normalizeScale(undefined) -> {1n,1n}, matching EvmWarpRouteReader.fetchScale's
+  // identity-collapse so both sides of the diff agree symmetrically.
+  clonedTokenConfig.scale = normalizeScale(clonedTokenConfig.scale);
+
   return sortArraysInObject(
     transformObj(clonedTokenConfig, transformWarpDeployConfigToCheck),
     sortArraysInConfigToCheck,