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## **Description**

This PR adopts the breaking changes from `@metamask/ramps-controller`
v3.1.0, which refactors the controller to use "userRegion" terminology
instead of "geolocation" and introduces proper initialization patterns.

### **Reason for Change**

The ramps-controller package was refactored to:
1. **Improve naming clarity**: "geolocation" implies a read-only,
automatically-detected value, but we plan to allow users to manually
change their region. The new "userRegion" terminology better reflects
that it's a user-selectable region.
2. **Add proper initialization**: Previously, consumers had to manually
call `updateGeolocation()` after creating the controller, which was
error-prone. The new `init()` method encapsulates initialization logic
and automatically fetches the user region at startup.
3. **Enable manual region setting**: The new `setUserRegion()` method
allows users to manually set their region without calling the
geolocation API, preparing for future UI features.

### **Changes in This PR**

#### **Selectors** (`app/selectors/rampsController/index.ts`)
- ✅ Removed deprecated `selectGeolocation` selector
- ✅ Removed deprecated `selectGeolocationRequest` selector  
- ✅ Added `selectUserRegion` selector (replaces `selectGeolocation`)
- ✅ Added `selectUserRegionRequest` selector (replaces
`selectGeolocationRequest`)

#### **Hooks** (`app/components/UI/Ramp/hooks/`)
- ✅ Renamed `useRampsGeolocation.ts` → `useRampsUserRegion.ts`
- ✅ Updated hook to use new `updateUserRegion()` and `setUserRegion()`
methods
- ✅ Updated hook to use new `selectUserRegion` and
`selectUserRegionRequest` selectors
- ✅ Updated all references and imports throughout the codebase

#### **Controller Initialization**
(`app/core/Engine/controllers/ramps-controller/ramps-controller-init.ts`)
- ✅ Updated to call `controller.init()` at startup (non-blocking)
- ✅ Initialization automatically fetches user region via geolocation API
- ✅ Errors are handled gracefully and available via selectors

#### **Tests**
- ✅ Updated `ramps-controller-init.test.ts` to test new `init()` method
- ✅ Updated `useRampsUserRegion.test.ts` to use new API and cache keys
- ✅ Updated selector tests to use `userRegion` state property
- ✅ All tests updated to use `'updateUserRegion'` cache key instead of
`'updateGeolocation'`

#### **Yarn Patch**
- ✅ Updated ramps-controller patch to include all local changes
(userRegion state, updateUserRegion, setUserRegion, init methods)

### **Migration Guide**

**Before:**
```ts
import { selectGeolocation, selectGeolocationRequest } from './selectors/rampsController';
import { useRampsGeolocation } from './hooks/useRampsGeolocation';

// Manual initialization required
Engine.context.RampsController.updateGeolocation();
```

**After:**
```ts
import { selectUserRegion, selectUserRegionRequest } from './selectors/rampsController';
import { useRampsUserRegion } from './hooks/useRampsUserRegion';

// Automatic initialization via controller.init() in ramps-controller-init.ts
```

### **Breaking Changes Adopted**

- ❌ `geolocation` state property → ✅ `userRegion`
- ❌ `updateGeolocation()` method → ✅ `updateUserRegion()`
- ❌ `selectGeolocation` selector → ✅ `selectUserRegion`
- ❌ `selectGeolocationRequest` selector → ✅ `selectUserRegionRequest`
- ❌ `useRampsGeolocation()` hook → ✅ `useRampsUserRegion()`

### **Related PRs**

- Core package PR:
[MetaMask/core#7563](MetaMask/core#7563) -
Refactors ramps-controller to use userRegion terminology and adds init()
method



## **Changelog**

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CHANGELOG entry: Adopted new ramp controller variable names

## **Related issues**

Fixes:

## **Manual testing steps**

```gherkin
Feature: my feature name

  Scenario: user [verb for user action]
    Given [describe expected initial app state]

    When user [verb for user action]
    Then [describe expected outcome]
```

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

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### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [ ] I’ve followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] 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](https://jsdoc.app/) format
if applicable
- [ ] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
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.



<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adopts the new `@metamask/ramps-controller` v3 APIs and init model.
> 
> - Migrate from `geolocation` to `userRegion`: new `useRampsUserRegion`
hook (with `fetchUserRegion` and `setUserRegion`), selectors
`selectUserRegion`/`selectUserRegionRequest` (retain `selectGeolocation`
aliases); update `useRampsGeolocation` to call `updateUserRegion`
> - Initialize controller via `controller.init()` at startup
(`ramps-controller-init`), replacing `updateGeolocation` side-effect
> - Refactor ramps service init: derive environment via
`getRampsEnvironment` and platform context via `getRampsContext` (uses
`Platform.OS`)
> - Update fixtures, snapshots, and tests accordingly (new request keys
`updateUserRegion:[]`, added `eligibility`/`tokens` fields)
> - Bump dependency to `@metamask/ramps-controller@^3.0.0`
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
c99674b. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->