feat: import newremote feature flag controller with override functionality #23487

asalsys · 2025-12-01T14:38:07Z

Description

This PR adds comprehensive override functionality to the RemoteFeatureFlagController that was added in this PR, allowing developers and users to locally override remote feature flags for testing and debugging purposes. The implementation also includes enhanced A/B test visibility features that provide access to available test groups.

What is the reason for the change?
The need to override remote feature flags locally for development, testing, and debugging scenarios without modifying the remote configuration.

What is the improvement/solution?

Added local override system that takes precedence over remote flags
Enhanced state management to track both remote flags and local overrides separately
Added A/B test raw flag storage to provide visibility into available test groups
Implemented comprehensive API methods for managing overrides and accessing flag information

Changelog

CHANGELOG entry: Added override functionality to remote feature flags with methods to set, get, clear overrides and access A/B test groups

Related issues

Fixes:

Manual testing steps

Feature: Remote Feature Flag Override Functionality

Scenario: user sets a local override for a feature flag
Given the RemoteFeatureFlagController is initialized with remote flags
When user calls setFlagOverride('testFlag', true)
Then testFlag selector should return the override value true
And getFlagOverride('testFlag') should return true

Scenario: user clears a specific flag override
Given a feature flag has a local override set
When user calls clearFlagOverride('testFlag')
Then testFlag selector should return the original remote value
And getFlagOverride('testFlag') should return undefined

Scenario: user accesses A/B test groups
Given remote flags contain A/B test configurations
When user calls rawProcessedRemoteFeatureFlags selector
Then it should return an array of available test groups with names and values

Screenshots/Recordings

Before

After

Pre-merge author checklist

I've followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
I've completed the PR template to the best of my ability
I've included tests if applicable
I've documented my code using JSDoc format if applicable
I've applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

github-actions · 2025-12-01T14:38:17Z

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

Cal-L

The engine ready checks might not be necessary assuming this context is used in the right place. We already have a ControllersGate that blocks the majority of components from rendering before the engine is initialized. Can we rely on that instead?

asalsys · 2025-12-03T22:55:21Z

The engine ready checks might not be necessary assuming this context is used in the right place. We already have a ControllersGate that blocks the majority of components from rendering before the engine is initialized. Can we rely on that instead?

Yes, correct, I don't think it is necessary at all. I had that logic because I was having trouble getting it to start I thought the issue was that the controller wasn't loading but it was because the controller was broken and wasn't building

…errides

github-actions · 2025-12-11T21:19:07Z

🔍 Smart E2E Test Selection

Selected E2E tags: SmokeCore, SmokeConfirmationsRedesigned, SmokeWalletPlatform, SmokeWalletUX, SmokeTrade, SmokeSwaps, SmokeStake, SmokeNotifications, SmokePerps, SmokeRamps, SmokePredictions, SmokeAssets, SmokeNetworkAbstractions, SmokeMultiChainPermissions
Risk Level: high
AI Confidence: 85%

click to see 🤖 AI reasoning details

This PR modifies the core feature flag infrastructure, specifically the selectRemoteFeatureFlags selector which is used in 50+ places across the codebase controlling behavior of virtually every major feature.

Key changes:

Modified selectRemoteFeatureFlags to merge localOverrides with remoteFeatureFlags - this is a fundamental behavioral change affecting how all feature flags are resolved
Added new selectors: selectLocalOverrides, selectRawFeatureFlags, selectrawRemoteFeatureFlags
Refactored FeatureFlagOverrideContext to use controller methods instead of local React state
Added A/B test flag type support
CRITICAL ISSUE: package.json points to a local file path (file:/Users/sallem/Desktop/...) which would break builds for anyone else - this appears to be an unintended development-time change

The selectRemoteFeatureFlags selector directly impacts:

Confirmations (signatures, staking, contract interactions, transfers, approves)
Bridge functionality
Notifications
Perps/Perpetuals trading
Predictions market
Earn/Staking
Ramps (buy/sell)
Network blacklists
Asset DeFi positions
Token search/discovery
Card features
Homepage carousel
And many more

Because this selector is foundational infrastructure that gates nearly every major feature, any subtle bugs in how overrides are merged could cause unexpected behavior across the entire app. The comprehensive tag selection ensures we catch any regressions in feature-flag-controlled functionality.

View GitHub Actions results

Cal-L

Left some comments

Cal-L · 2025-12-11T21:46:27Z

app/components/Views/FeatureFlagOverride/FeatureFlagOverride.tsx

          />
        );
+      case 'abTest': {
+        interface AbTestType {


Move type outside of component

Cal-L · 2025-12-11T21:47:29Z

app/components/Views/FeatureFlagOverride/FeatureFlagOverride.tsx

            ios_backgroundColor={theme.colors.border.muted}
          />
        );
+      case 'abTest': {


While extracting types, also cleaner to extract these into enums

Cal-L · 2025-12-11T22:11:12Z

app/contexts/FeatureFlagOverrideContext.tsx

-  // Local state for overrides
-  const [overrides, setOverrides] = useState<FeatureFlagOverrides>({});
+  // Subscribe to controller state changes to ensure we stay in sync
+  useEffect(() => {


This doesn't seem like it should do anything since it's triggering an empty function from inside of the useEffect. What's the intended purpose here - is it to get the latest state every time the feature flag changes?

Cal-L · 2025-12-11T22:12:38Z

app/contexts/FeatureFlagOverrideContext.tsx

+}
+
+// Helper to safely access the RemoteFeatureFlagController with proper typing
+const getRemoteFeatureFlagController = ():


This does not need to be a function since it's just returning a reference

Cal-L · 2025-12-11T22:32:33Z

app/contexts/FeatureFlagOverrideContext.tsx

+    | undefined;
+
+// Helper to safely execute controller methods with error handling
+const withRemoteFeatureFlagController = (


the with naming convention is usually used for higher order wrappers, which typically used to wrap classes or functional components. Following the logic, it looks like this is intended to handle catching error on method calls for the remote feature flag controller. A few suggestions to make this cleaner:

Create a remote feature flag hook instead, useRemoteFeatureFlagController

In the hook, return remote feature flag functions that gracefully handle method call failures

Cal-L · 2025-12-11T22:33:19Z

app/selectors/featureFlagController/index.ts

 export const selectRemoteFeatureFlags = createSelector(
  selectRemoteFeatureFlagControllerState,
-  (remoteFeatureFlagControllerState) => {
+  (remoteFeatureFlagControllerState: unknown) => {


We should use the state type from RemoteFeatureFlagController

Cal-L · 2025-12-11T22:34:19Z

app/util/feature-flags/index.ts

    | 'array'
    | 'boolean with minimumVersion'
    | 'boolean nested'
+    | 'abTest'


Cleaner to abstract these into an enum

metamaskbot added the team-mobile-platform Mobile Platform team label Dec 1, 2025

github-actions bot added the size-M label Dec 1, 2025

asalsys changed the title ~~import local remote feature flag~~ feat: import newremote feature flag controller with override functionality Dec 2, 2025

Cal-L reviewed Dec 3, 2025

View reviewed changes

asalsys added 5 commits December 10, 2025 16:27

import local remote feature flag

579e947

fix import issue and working remote-feature-flag-controller

5587dfe

support ab-test options

369d995

remove engine ready

caaafbf

update abTestRawFlags to rawProcessedRemoteFeatureFlags

06336f2

asalsys force-pushed the use-updated-remote-feature-flag-to-handle-overrides branch from 8003948 to 06336f2 Compare December 10, 2025 21:28

asalsys requested a review from Cal-L December 10, 2025 21:29

asalsys added 2 commits December 11, 2025 13:11

Merge branch 'main' into use-updated-remote-feature-flag-to-handle-ov…

eee57f6

…errides

update the rawFeatureFlag options

4cdecbd

Cal-L reviewed Dec 11, 2025

View reviewed changes

asalsys self-assigned this Dec 12, 2025

asalsys mentioned this pull request Dec 12, 2025

feat: add override functionality to remote feature flags MetaMask/core#7271

Open

4 tasks

Uh oh!

feat: import newremote feature flag controller with override functionality #23487

Are you sure you want to change the base?

feat: import newremote feature flag controller with override functionality #23487

Conversation

asalsys commented Dec 1, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Description

Changelog

Related issues

Manual testing steps

Screenshots/Recordings

Before

After

Pre-merge author checklist

Pre-merge reviewer checklist

Uh oh!

github-actions bot commented Dec 1, 2025

Uh oh!

Cal-L left a comment

Choose a reason for hiding this comment

Uh oh!

asalsys commented Dec 3, 2025

Uh oh!

github-actions bot commented Dec 11, 2025

🔍 Smart E2E Test Selection

Uh oh!

Cal-L left a comment

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Cal-L Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

asalsys commented Dec 1, 2025 •

edited

Loading