bp_get_user_groups( int $user_id, array $args = array() )

function bp_get_user_groups( $user_id, $args = array() ) {
	$r = bp_parse_args( $args, array(
		'is_confirmed' => true,
		'is_banned'    => false,
		'is_admin'     => false,
		'is_mod'       => false,
		'invite_sent'  => null,
		'orderby'      => 'group_id',
		'order'        => 'ASC',
	), 'get_user_groups' );

	$user_id = intval( $user_id );

	$membership_ids = wp_cache_get( $user_id, 'bp_groups_memberships_for_user' );
	if ( false === $membership_ids ) {
		$membership_ids = BP_Groups_Member::get_membership_ids_for_user( $user_id );
		wp_cache_set( $user_id, $membership_ids, 'bp_groups_memberships_for_user' );
	}

	// Prime the membership cache.
	$uncached_membership_ids = bp_get_non_cached_ids( $membership_ids, 'bp_groups_memberships' );
	if ( ! empty( $uncached_membership_ids ) ) {
		$uncached_memberships = BP_Groups_Member::get_memberships_by_id( $uncached_membership_ids );

		foreach ( $uncached_memberships as $uncached_membership ) {
			wp_cache_set( $uncached_membership->id, $uncached_membership, 'bp_groups_memberships' );
		}
	}

	// Assemble filter array for use in `wp_list_filter()`.
	$filters = wp_array_slice_assoc( $r, array( 'is_confirmed', 'is_banned', 'is_admin', 'is_mod', 'invite_sent' ) );
	foreach ( $filters as $filter_name => $filter_value ) {
		if ( is_null( $filter_value ) ) {
			unset( $filters[ $filter_name ] );
		}
	}

	// Populate group membership array from cache, and normalize.
	$groups    = array();
	$int_keys  = array( 'id', 'group_id', 'user_id', 'inviter_id' );
	$bool_keys = array( 'is_admin', 'is_mod', 'is_confirmed', 'is_banned', 'invite_sent' );
	foreach ( $membership_ids as $membership_id ) {
		$membership = wp_cache_get( $membership_id, 'bp_groups_memberships' );

		// Sanity check.
		if ( ! isset( $membership->group_id ) ) {
			continue;
		}

		// Integer values.
		foreach ( $int_keys as $index ) {
			$membership->{$index} = intval( $membership->{$index} );
		}

		// Boolean values.
		foreach ( $bool_keys as $index ) {
			$membership->{$index} = (bool) $membership->{$index};
		}

		foreach ( $filters as $filter_name => $filter_value ) {
			if ( ! isset( $membership->{$filter_name} ) || $filter_value != $membership->{$filter_name} ) {
				continue 2;
			}
		}

		$group_id = (int) $membership->group_id;

		$groups[ $group_id ] = $membership;
	}

	// By default, results are ordered by membership id.
	if ( 'group_id' === $r['orderby'] ) {
		ksort( $groups );
	} elseif ( in_array( $r['orderby'], array( 'id', 'date_modified' ) ) ) {
		$groups = bp_sort_by_key( $groups, $r['orderby'] );
	}

	// By default, results are ordered ASC.
	if ( 'DESC' === strtoupper( $r['order'] ) ) {
		// `true` to preserve keys.
		$groups = array_reverse( $groups, true );
	}

	return $groups;
}