HighFile-scopeJavaScript / TypeScript Plug & play

Provide error handlers to subscription/listener APIs

When subscribing to streams/listeners, always provide an error handler and a deterministic unsubscribe/cleanup path.

Why this matters

Prevents silent drops and resource leaks.

Side-by-side examples engineers can pattern-match during review.

Avoid

emitter.on('data', onData); // no error/cleanup

Prefer

emitter.on('data', onData); emitter.on('error', (err)=>logger.error('stream',{err})); const off=()=>emitter.off('data',onData);

Bad

ws.onmessage = onMsg

Good

ws.onmessage = onMsg; ws.onerror = onErr; ws.onclose = onClose

From the same buckets as this rule.

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Critical
Avoid Returning Null in Non-Async Task Methods
Returning null from a Task or Task<T> method causes a NullReferenceException if awaited. Use Task.CompletedTask or Task.FromResult<T>(null) instead.
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Critical
Avoid Using Boolean Expressions in `except` Statements
Detect `except` clauses that use `or` or `and` to catch multiple exceptions. This does not work as intended. Recommend using a tuple of exceptions instead.
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