Check error handling

Inspect JavaScript text for four visible error-handling omissions without treating regex matches as proof.

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ToolError Handling Checker
Input
Output
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Preview

How it works

The four patterns cover an empty catch, awaited fetch with no visible ok or status token, a Promise constructor with no reject text, and JSON.parse without a preceding try. It has no syntax tree and cannot connect a status check, catch, or rejection path to the operation it appears beside.

  • Only JavaScript source text is considered.
  • Zero findings is not promoted to a pass because most runtime error paths are outside these patterns.

Worked example

Check error handling
Input
											async function load(){ const response = await fetch(url); return response.json(); }
Output
												Issues: fetch resolves on HTTP errors; check response.ok or status.
Issue count: 1

When to use this

Fetch wrappers expose missing status checks, ingestion boundaries review JSON parsing, and Promise constructors are checked for a visible rejection path.

Edge cases

  • An unrelated response.ok elsewhere can suppress the fetch warning.
  • The word reject inside a comment can hide the Promise-constructor warning.
  • Promise chains, callback errors, event handlers, and framework error boundaries are not examined.

References