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typescript.bare_catch

Correctness Medium

Detects catch blocks that blindly catch all errors without proper type checking.

Why It Matters

Bare catch blocks:

Swallow important errors — Can’t distinguish error types
Mask bugs — Programming errors caught as expected errors
Poor recovery — Wrong error handling logic applied

Example

// ❌ Before (bare catch)
try {
  await fetchData();
} catch (e) {
  console.log("Failed to fetch"); // What if 'e' is a TypeError?
}

// ✅ After (typed error handling)
import { isAxiosError } from 'axios';

try {
  await fetchData();
} catch (error) {
  if (isAxiosError(error)) {
    if (error.response?.status === 404) {
      return null;
    }
    logger.error('API error', { status: error.response?.status });
  } else if (error instanceof Error) {
    logger.error('Unexpected error', { message: error.message });
  }
  throw error;
}

What Unfault Detects

catch(e) without type narrowing
Missing instanceof checks
No error classification logic

Auto-Fix

Unfault can add error type guards and proper handling structure.