$terms = get_terms( \'custom_taxonomy\', array(
    \'hide_empty\' => false,
));

foreach( $terms as $term ) {
    $args = [
        \'post_type\'   => \'custom_post_type\', 
        \'post_status\' => \'publish\',
        \'tax_query\'   => [
            [
                \'taxonomy\' => \'custom_taxonomy\',
                \'field\'    => \'id\',
                \'terms\'    => $term->term_id,
            ]
        ]
    ];

    $posts = new WP_Query( $args );

    $result[ $term->term_id ] = $posts->posts;

}

$result[TERMID\\u 1]=数组（POST\\u OBJECT\\u OF\\u TERMID\\u 1）；

$result[TERMID\\u 2]=数组（POST\\u OBJECT\\u OF\\u TERMID\\u 2）；

$result[TERMID\\u 3]=数组（POST\\u OBJECT\\u OF\\u TERMID\\u 3）；