/kotlin-review

description: Comprehensive Kotlin code review for idiomatic patterns, null safety, coroutine safety, and security. Invokes the kotlin-reviewer agent.

Kotlin Code Review

This command invokes the **kotlin-reviewer** agent for comprehensive Kotlin-specific code review.

What This Command Does

1. **Identify Kotlin Changes**: Find modified `.kt` and `.kts` files via `git diff` 2. **Run Build & Static Analysis**: Execute `./gradlew build`, `detekt`, `ktlintCheck` 3. **Security Scan**: Check for SQL injection, command injection, hardcoded secrets 4. **Null Safety Review**: Analyze `!!` usage, platform type handling, unsafe casts 5. **Coroutine Review**: Check structured concurrency, dispatcher usage, cancellation 6. **Generate Report**: Categorize issues by severity

When to Use

Use `/kotlin-review` when:

• After writing or modifying Kotlin code
• Before committing Kotlin changes
• Reviewing pull requests with Kotlin code
• Onboarding to a new Kotlin codebase
• Learning idiomatic Kotlin patterns

Review Categories

CRITICAL (Must Fix)

• SQL/Command injection vulnerabilities
• Force-unwrap `!!` without justification
• Platform type null safety violations
• GlobalScope usage (structured concurrency violation)
• Hardcoded credentials
• Unsafe deserialization

HIGH (Should Fix)

• Mutable state where immutable suffices
• Blocking calls inside coroutine context
• Missing cancellation checks in long loops
• Non-exhaustive `when` on sealed types
• Large functions (>50 lines)
• Deep nesting (>4 levels)

MEDIUM (Consider)

• Non-idiomatic Kotlin (Java-style patterns)
• Missing trailing commas
• Scope function misuse or nesting
• Missing sequence for large collection chains
• Redundant explicit types

Automated Checks Run

# Build check
./gradlew build

# Static analysis
./gradlew detekt

# Formatting check
./gradlew ktlintCheck

# Tests
./gradlew test

Example Usage

User: /kotlin-review

Agent:
# Kotlin Code Review Report

## Files Reviewed
- src/main/kotlin/com/example/service/UserService.kt (modified)
- src/main/kotlin/com/example/routes/UserRoutes.kt (modified)

## Static Analysis Results
✓ Build: Successful
✓ detekt: No issues
WARNING: ktlint: 2 formatting warnings

## Issues Found

[CRITICAL] Force-Unwrap Null Safety
File: src/main/kotlin/com/example/service/UserService.kt:28
Issue: Using !! on nullable repository result
```kotlin
val user = repository.findById(id)!!  // NPE risk

Fix: Use safe call with error handling

val user = repository.findById(id)
    ?: throw UserNotFoundException("User $id not found")

[HIGH] GlobalScope Usage File: src/main/kotlin/com/example/routes/UserRoutes.kt:45 Issue: Using GlobalScope breaks structured concurrency

GlobalScope.launch {
    notificationService.sendWelcome(user)
}

Fix: Use the call's coroutine scope

launch {
    notificationService.sendWelcome(user)
}

Summary

• CRITICAL: 1
• HIGH: 1
• MEDIUM: 0

Recommendation: FAIL: Block merge until CRITICAL issue is fixed

## Approval Criteria

| Status | Condition |
|--------|-----------|
| PASS: Approve | No CRITICAL or HIGH issues |
| WARNING: Warning | Only MEDIUM issues (merge with caution) |
| FAIL: Block | CRITICAL or HIGH issues found |

## Integration with Other Commands

- Use `/kotlin-test` first to ensure tests pass
- Use `/kotlin-build` if build errors occur
- Use `/kotlin-review` before committing
- Use `/code-review` for non-Kotlin-specific concerns

## Related

- Agent: `agents/kotlin-reviewer.md`
- Skills: `skills/kotlin-patterns/`, `skills/kotlin-testing/`