fix: no-sparse-arrays should not flag destructuring assignment targets#1242
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TypeScript's AST parses destructuring assignment targets (e.g. `[, a] = b`) as ArrayLiteralExpression, same as array literals, so omitted elements used to skip items were misflagged as sparse arrays. Skip nodes that are assignment targets, matching ESLint's behavior.
fansenze
approved these changes
Jul 9, 2026
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Summary
no-sparse-arrayswas flagging destructuring assignment targets like[, suggestion] = await all()as sparse arrays. TypeScript's AST parses these asArrayLiteralExpression(same node kind as real array literals), so omitted elements used to skip items during destructuring were incorrectly treated as sparse-array holes. ESLint's own rule only checksArrayExpressionnodes and never flags this, since espree gives destructuring targets a distinctArrayPatternkind. Fixed by skipping nodes whereast.IsAssignmentTarget(node)is true, verified against real ESLint 8 output for both the valid destructuring cases and the still-invalid genuine sparse array literals.Related Links
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