require-array-join-separator

Require an explicit array join separator

Array.join() silently selects a comma as its separator.
Instead, you SHOULD pass the intended separator explicitly.

- Category: style
- Level: warning
- Fix: automatic
- Scope: module

Reported

function commaSeparated(values: string[]): string {
    return values.join();
}
Accepted

function commaSeparated(values: string[]): string {
    return values.join(",");
}
Prior art

- eslint-plugin-unicorn · require-array-join-separator

language/linter/src/rules/style/requirearrayjoinseparator.rs:8