Environment variable validation

Environment variables should be properly validated with correct type checking and without redundant conditions. Common issues include comparing strings to integers and using unnecessary double-checks that can lead to unexpected behavior.

Key principles:

1. Avoid redundant checks: Don’t check if an environment variable exists and then check its value in the same condition
2. Use correct types: Environment variables are always strings, so compare against string values
3. Simplify boolean logic: Use direct comparisons instead of complex conditional chains

Examples of issues and fixes:

❌ Problematic patterns:

# Redundant checking
if ENV["RCT_USE_PREBUILT_RNCORE"] && ENV["RCT_USE_PREBUILT_RNCORE"] == "1"

# Type mismatch - comparing string to integer
return ENV["RCT_NEW_ARCH_ENABLED"] == 0 ? false : true

✅ Improved patterns:

# Direct value check
if ENV["RCT_USE_PREBUILT_RNCORE"] == "1"

# Correct string comparison with simplified logic
return ENV["RCT_NEW_ARCH_ENABLED"] != "0"

This approach prevents runtime errors, improves code readability, and ensures consistent behavior across different environments and deployment scenarios.