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go.panic_in_library

Stability High

Detects panic() calls in library code that should return errors instead.

Why It Matters

Panics in libraries:

Crash calling applications — Library panic terminates the app
Remove caller control — Callers can’t handle errors gracefully
Violate Go conventions — Libraries should return errors
Cause production outages — One bad input crashes everything

Example

// ❌ Before (panic in library)
func Parse(data []byte) Config {
    if len(data) == 0 {
        panic("empty data") // Crashes caller!
    }
    // ...
}

// ✅ After (returns error)
func Parse(data []byte) (Config, error) {
    if len(data) == 0 {
        return Config{}, errors.New("empty data")
    }
    // ...
}

What Unfault Detects

panic() in exported functions
panic() in package without main
panic() for recoverable errors

Auto-Fix

Unfault converts panic to error return:

func Process(input string) (Result, error) {
    if input == "" {
        return Result{}, errors.New("empty input")
    }
    // ...
}