mobile-i18n-strings.mdc

---
description: Flag hardcoded user-facing strings that are not wrapped in a translation function. Catches strings in JSX text nodes and Flutter Text widgets that bypass the i18n layer.
alwaysApply: false
globs:
  - "**/*.ts"
  - "**/*.tsx"
  - "**/*.dart"
standards-version: 1.6.3
---

# I18n Strings

Flag these internationalization issues:

## Hardcoded strings in JSX

- A `<Text>` component contains a raw string literal instead of a translation call like `t("key")` or `intl.formatMessage()`.
- String props that are user-visible (placeholder, title, label, accessibilityLabel) use a hardcoded English string instead of a translated value.
- Exception: strings that are not user-facing (testID values, console.log messages, error codes) do not need translation.

**Fix:** Wrap the string in a translation function:

```tsx
// Before
<Text>Welcome back</Text>

// After
<Text>{t("home.welcomeBack")}</Text>
```

## Hardcoded strings in Flutter Text widgets

- A `Text()` widget contains a raw string literal instead of `AppLocalizations.of(context)!.key` or equivalent.
- Exception: debug-only strings, Key values, and route names do not need translation.

**Fix:**

```dart
// Before
Text('Welcome back')

// After
Text(AppLocalizations.of(context)!.welcomeBack)
```

## String concatenation for sentences

- Building user-visible sentences with `+` or template literals instead of using interpolation in the translation file. Concatenation breaks in languages with different word order.

**Fix:** Use interpolation parameters:

```tsx
// Before
<Text>{"Hello " + user.name}</Text>

// After
<Text>{t("greeting", { name: user.name })}</Text>
```

With the translation file:

```json
{ "greeting": "Hello {{name}}" }
```

## Missing plural forms

- Displaying counts with simple conditional (`count === 1 ? "item" : "items"`) instead of ICU plural syntax in the translation file.

**Fix:** Use plural-aware translation keys:

```json
{
  "itemCount_one": "{{count}} item",
  "itemCount_other": "{{count}} items"
}
```