feat(linter): implement eslint/no-sequences rule

[tt-a1i]

Summary

Implements the eslint/no-sequences rule that disallows the use of the comma operator.

The comma operator evaluates each of its operands (from left to right) and returns the value of the last operand. However, this frequently obscures side effects, and its use is often an accident.

Features

• Allows comma operator in for loop init and update expressions (standard JS pattern)
• allowInParentheses option (default: true) allows sequences wrapped in parentheses
• For grammar positions requiring parentheses (if, while, do-while, switch, with), double parentheses are needed to indicate intentionality

Examples

Incorrect:

foo = doSomething(), val;
0, eval("doSomething();");
do {} while ((doSomething(), !!test)); // needs double parens

Correct:

foo = (doSomething(), val);
(0, eval)("doSomething();");
do {} while (((doSomething(), !!test))); // double parens
for (i = 0, j = 10; i < j; i++, j--) {} // for loop allowed

Closes #481 (partially - adds no-sequences)

[codspeed-hq]

CodSpeed Performance Report

Merging #16872 will not alter performance

_{Comparing tt-a1i:feat/linter-no-sequences (3691618) with main (bb86e0e)}

Summary

✅ 4 untouched
⏩ 41 skipped¹

Footnotes

1. 41 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[camc314]

Thank you