Check common code bug

How it works

JavaScript mode looks for assignment inside if, async callbacks passed to forEach, and loose equality; Python mode looks for bare except, an empty-list default, and identity against a literal. These are regular-expression matches with no parser, scope graph, type system, or control-flow model.

• JavaScript is the initial dialect and selecting Python replaces its pattern set.
• Zero findings means only that the chosen three expressions did not match.

Worked example

											Code: if (value = 3) { console.log(value) }
array.forEach(async item => await save(item))
Language: javascript
										

												Issues: Possible assignment inside a condition., forEach does not await async callbacks.
Issue count: 2
Note: Heuristic review only; run the language compiler, tests and a dedicated linter.
											

When to use this

Review preflights highlight async forEach, Python snippets expose shared list defaults, and teaching exercises compare heuristics with compiler and linter results.

Edge cases

• Pattern text inside comments or strings can produce a false warning.
• Equivalent bugs with unusual whitespace or nested syntax can evade the expressions.
• No finding establishes neither runtime correctness nor test coverage.