wp-includes/class-wp-scripts.php:665Sets handle group.
$handlestring$recursionbool$groupint|falseoptionalfalsebool public function set_group( $handle, $recursion, $group = false ) { if ( isset( $this->registered[ $handle ]->args ) && 1 === $this->registered[ $handle ]->args ) { $calculated_group = 1; } else { $calculated_group = (int) $this->get_data( $handle, 'group' ); } if ( false !== $group && $calculated_group > $group ) { $calculated_group = $group; } return parent::set_group( $handle, $recursion, $calculated_group ); }Introduced in 2.8.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-scripts.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.