fix: don't use cachedRoutes if intent.caching (1% experiment) (#833)

* fix: don't use cachedRoutes if intent.caching (1% experiment)

* invert experiment flag

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@uniswap/smart-order-router",
-  "version": "4.19.0",
+  "version": "4.19.1",
   "description": "Uniswap Smart Order Router",
   "main": "build/main/index.js",
   "typings": "build/main/index.d.ts",

src/routers/alpha-router/alpha-router.ts

@@ -1470,7 +1470,11 @@ export class AlphaRouter
           : 'N/A',
     });
 
-    if (routingConfig.useCachedRoutes && cacheMode !== CacheMode.Darkmode) {
+    if (
+      routingConfig.useCachedRoutes &&
+      cacheMode !== CacheMode.Darkmode &&
+      AlphaRouter.isAllowedToEnterCachedRoutes(routingConfig.intent)
+    ) {
       if (enabledAndRequestedProtocolsMatch) {
         if (
           protocols.includes(Protocol.V4) &&
@@ -3195,4 +3199,23 @@ export class AlphaRouter
       }
     );
   }
+
+  // Percentage of time we want to skip cached routes for the experiment.
+  // Starting with 1% to gradually roll out the change.
+  public static readonly CACHED_ROUTES_SKIP_EXPERIMENT_FLAG_PERCENTAGE = 0.01;
+
+  // We want to skip cached routes access whenever "intent === INTENT.CACHING".
+  // To verify this functionality though, we want to start by using a percentage of the time.
+  public static isAllowedToEnterCachedRoutes(intent?: INTENT): boolean {
+    // Check if we should run the experiment
+    const shouldRunExperiment =
+      Math.random() < AlphaRouter.CACHED_ROUTES_SKIP_EXPERIMENT_FLAG_PERCENTAGE;
+    if (shouldRunExperiment) {
+      // For the experiment group, we want to skip the cached routes access if the intent is caching
+      return intent !== INTENT.CACHING;
+    }
+
+    // For the control group, we always allow access to cached routes.
+    return true;
+  }
 }

test/unit/routers/alpha-router/alpha-router.test.ts

@@ -111,6 +111,7 @@ import {
 import {
   InMemoryRouteCachingProvider
 } from '../../providers/caching/route/test-util/inmemory-route-caching-provider';
+import { INTENT } from '../../../../src/util/intent';
 
 const helper = require('../../../../src/routers/alpha-router/functions/calculate-ratio-amount-in');
 
@@ -1616,9 +1617,9 @@ describe('alpha router', () => {
         });
 
         test('with V1.2 - skips cache when V2 is missing from requested protocols', async () => {
-          const v1_2Params = { 
-            ...swapParams, 
-            version: UniversalRouterVersion.V1_2 
+          const v1_2Params = {
+            ...swapParams,
+            version: UniversalRouterVersion.V1_2
           };
 
           const swap = await alphaRouter.route(
@@ -3087,6 +3088,34 @@ describe('alpha router', () => {
       });
     });
   });
+
+  describe('isAllowedToEnterCachedRoutes', () => {
+    let randomStub: sinon.SinonStub;
+
+    beforeEach(() => {
+      randomStub = sinon.stub(Math, 'random');
+    });
+
+    afterEach(() => {
+      randomStub.restore();
+    });
+
+    test('returns correct values based on random percentage and intent', () => {
+      // Test when random is above experiment threshold (control group - should always return true)
+      randomStub.returns(AlphaRouter.CACHED_ROUTES_SKIP_EXPERIMENT_FLAG_PERCENTAGE + 0.01);
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(INTENT.CACHING)).toBe(true);
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(INTENT.QUOTE)).toBe(true);
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(undefined)).toBe(true);
+
+      // Test when random is below experiment threshold (experiment group)
+      randomStub.returns(AlphaRouter.CACHED_ROUTES_SKIP_EXPERIMENT_FLAG_PERCENTAGE - 0.001);
+      // Should return false only for CACHING intent
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(INTENT.CACHING)).toBe(false);
+      // Should return true for other intents
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(INTENT.QUOTE)).toBe(true);
+      expect(AlphaRouter.isAllowedToEnterCachedRoutes(undefined)).toBe(true);
+    });
+  });
 });
 
 type GetQuotesManyExactInFnParams = {