RFC: address CI failures from unused "eslint-disable no-new-wrappers" in @stdlib/assert examples #8244

Summary

Multiple example files under the @stdlib/assert/**/examples/index.js path contain an unnecessary /* eslint-disable no-new-wrappers */ directive. Because CI runs ESLint with the --report-unused-disable-directives flag, these unused directives are reported as errors when the files are randomly selected for linting. This results in non-deterministic CI build failures.

This issue is an extension of issue #8235, which fixed a single instance in the is-nonpositive-integer-array package. However, the same pattern exists broadly across other example files within the @stdlib/assert module. Because the lint_random_files workflow lints a random subset of files on each run, leaving these other unused directives in place will lead to future intermittent failures. Therefore, this issue aims to track a systematic cleanup to eradicate this class of non-deterministic failures.

Root Cause

The no-new-wrappers ESLint rule is intended to disallow using the new operator with the global Number, String, and Boolean wrapper constructors. In the affected example files, the disable directive is unused for one of two reasons:

1. No Wrapper Constructors Used: The code does not use calls like new Number(...) at all.
2. Constructor Is Locally Shadowed: The code imports a local constructor via a statement like var Number = require('@stdlib/number/ctor');. Subsequent calls to new Number(...) invoke this local variable, not the global wrapper constructor, so the no-new-wrappers rule is never triggered.

Affected Files

The pattern of unused no-new-wrappers directives has been identified in the 38 files listed below within the @stdlib/assert scope.

A representative subset includes:

• lib/node_modules/@stdlib/assert/is-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-integer-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-prime/examples/index.js
• lib/node_modules/@stdlib/assert/is-finite/examples/index.js (Special combined case)

Click to expand the full list of 38 affected files

• lib/node_modules/@stdlib/assert/is-boolean-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-boolean/examples/index.js
• lib/node_modules/@stdlib/assert/is-composite/examples/index.js
• lib/node_modules/@stdlib/assert/is-cube-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-even/examples/index.js
• lib/node_modules/@stdlib/assert/is-finite-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-finite/examples/index.js
• lib/node_modules/@stdlib/assert/is-infinite/examples/index.js
• lib/node_modules/@stdlib/assert/is-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-nan-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-nan/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-integer-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-number-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-negative-zero/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonnegative-integer-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonnegative-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonnegative-number-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonnegative-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonpositive-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonpositive-number-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-nonpositive-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-number-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-odd/examples/index.js
• lib/node_modules/@stdlib/assert/is-positive-integer-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-positive-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-positive-number-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-positive-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-positive-zero/examples/index.js
• lib/node_modules/@stdlib/assert/is-prime/examples/index.js
• lib/node_modules/@stdlib/assert/is-probability/examples/index.js
• lib/node_modules/@stdlib/assert/is-safe-integer-array/examples/index.js
• lib/node_modules/@stdlib/assert/is-safe-integer/examples/index.js
• lib/node_modules/@stdlib/assert/is-square-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-square-triangular-number/examples/index.js
• lib/node_modules/@stdlib/assert/is-triangular-number/examples/index.js

Proposal

1. Remove Unused Directives: Remove the file-level /* eslint-disable no-new-wrappers */ directive in all files where it is verifiably unused.
2. Handle Combined Directives: For combined disable directives, remove only the unused no-new-wrappers part.
   • Example: In is-finite/examples/index.js, change /* eslint-disable no-new-wrappers, stdlib/no-redeclare */ to /* eslint-disable stdlib/no-redeclare */.

Selection Rules

• Remove the directive when:

  • No new Number, new String, or new Boolean is present.
  • new Number or new Boolean is present, but its constructor has been locally shadowed by @stdlib/*/ctor.

• Keep the directive when:

  • The example uses a global wrapper constructor (e.g., new String(...) without local shadowing), and removing the directive would cause an ESLint error.

Execution Plan

To avoid triggering an "Argument list too long" error in CI, this work can be submitted via multiple small PRs, with each PR modifying a few packages.

References

• The no-new-wrappers rule is set to "warn" in the examples ESLint config: etc/eslint/.eslintrc.examples.js:44
• CI invokes ESLint with the --report-unused-disable-directives flag: tools/make/lib/lint/javascript/eslint.mk:50