日付の文字がsafariでNaNになる

Question

javascriptで日付をYYYY年MM月DD日表示になるよう指定していますが、safariのみNaN年aN月aN日になってしまいます。（Chrome、firefoxは問題なく表示されます。）
いろいろ試してみましたがどうしても直りません。
何か方法ありますでしょうか？

コード記載します。

function formatDate(date, format) {
if (!format) format = 'YYYY-MM-DD hh:mm:ss.SSS';
format = format.replace(/YYYY/g, date.getFullYear());
format = format.replace(/MM/g, ('0' + (date.getMonth() + 1)).slice(-2));
format = format.replace(/DD/g, ('0' + date.getDate()).slice(-2));
format = format.replace(/hh/g, ('0' + date.getHours()).slice(-2));
format = format.replace(/mm/g, ('0' + date.getMinutes()).slice(-2));
format = format.replace(/ss/g, ('0' + date.getSeconds()).slice(-2));
if (format.match(/S/g)) {
var milliSeconds = ('00' + date.getMilliseconds()).slice(-3);
var length = format.match(/S/g).length;
for (var i = 0; i < length; i++) format = format.replace(/S/, milliSeconds.substring(i, i + 1));
}
return format;
}

_createListItemView: function (post) {
var $item = this.$listItemTpl.clone();
$item.find('.type .value').empty().text(post.news_type);
$item.find('.title').empty().text(post.title);
$item.find('.date').empty().text(formatDate(new Date(post.post_date), 'YYYY年MM月DD日'));
$item.find('.newsLink').attr('href', post.url);
return $item.get(0);
},

Answer 1

post.post_dateの書式はどのようなものでしょうか。

new Date(文字列)でパースできる書式は、ブラウザによって異なります。

Comments

[退会済みユーザー]

wordpressのオリジナルテーマなので、おそらくwp-admin>includes>templeate.phpのデータを読み込んでいると思われます。

<div class="hidden" id="inline_' . $post->ID . '">
<div class="post_title">' . $title . '</div>' .
/** This filter is documented in wp-admin/edit-tag-form.php */
'<div class="post_name">' . apply_filters( 'editable_slug', $post->post_name, $post ) . '</div>
<div class="post_author">' . $post->post_author . '</div>
<div class="comment_status">' . esc_html( $post->comment_status ) . '</div>
<div class="ping_status">' . esc_html( $post->ping_status ) . '</div>
<div class="_status">' . esc_html( $post->post_status ) . '</div>
<div class="jj">' . mysql2date( 'd', $post->post_date, false ) . '</div>
<div class="mm">' . mysql2date( 'm', $post->post_date, false ) . '</div>
<div class="aa">' . mysql2date( 'Y', $post->post_date, false ) . '</div>
<div class="hh">' . mysql2date( 'H', $post->post_date, false ) . '</div>
<div class="mn">' . mysql2date( 'i', $post->post_date, false ) . '</div>
<div class="ss">' . mysql2date( 's', $post->post_date, false ) . '</div>
<div class="post_password">' . esc_html( $post->post_password ) . '</div>';

function touch_time( $edit = 1, $for_post = 1, $tab_index = 0, $multi = 0 ) {
global $wp_locale;
$post = get_post();

if ( $for_post )
$edit = ! ( in_array($post->post_status, array('draft', 'pending') ) && (!$post->post_date_gmt || '0000-00-00 00:00:00' == $post->post_date_gmt ) );

$tab_index_attribute = '';
if ( (int) $tab_index > 0 )
$tab_index_attribute = " tabindex=\"$tab_index\"";

// todo: Remove this?
// echo '<label for="timestamp" style="display: block;"><input type="checkbox" class="checkbox" name="edit_date" value="1" id="timestamp"'.$tab_index_attribute.' /> '.__( 'Edit timestamp' ).'</label><br />';

$time_adj = current_time('timestamp');
$post_date = ($for_post) ? $post->post_date : get_comment()->comment_date;
$jj = ($edit) ? mysql2date( 'd', $post_date, false ) : gmdate( 'd', $time_adj );
$mm = ($edit) ? mysql2date( 'm', $post_date, false ) : gmdate( 'm', $time_adj );
$aa = ($edit) ? mysql2date( 'Y', $post_date, false ) : gmdate( 'Y', $time_adj );
$hh = ($edit) ? mysql2date( 'H', $post_date, false ) : gmdate( 'H', $time_adj );
$mn = ($edit) ? mysql2date( 'i', $post_date, false ) : gmdate( 'i', $time_adj );
$ss = ($edit) ? mysql2date( 's', $post_date, false ) : gmdate( 's', $time_adj );

$cur_jj = gmdate( 'd', $time_adj );
$cur_mm = gmdate( 'm', $time_adj );
$cur_aa = gmdate( 'Y', $time_adj );
$cur_hh = gmdate( 'H', $time_adj );
$cur_mn = gmdate( 'i', $time_adj );

$month = '<label><span class="screen-reader-text">' . __( 'Month' ) . '</span><select ' . ( $multi ? '' : 'id="mm" ' ) . 'name="mm"' . $tab_index_attribute . ">\n";
for ( $i = 1; $i < 13; $i = $i +1 ) {
$monthnum = zeroise($i, 2);
$monthtext = $wp_locale->get_month_abbrev( $wp_locale->get_month( $i ) );
$month .= "\t\t\t" . '<option value="' . $monthnum . '" data-text="' . $monthtext . '" ' . selected( $monthnum, $mm, false ) . '>';
/* translators: 1: month number (01, 02, etc.), 2: month abbreviation */
$month .= sprintf( __( '%1$s-%2$s' ), $monthnum, $monthtext ) . "</option>\n";
}
$month .= '</select></label>';

$day = '<label><span class="screen-reader-text">' . __( 'Day' ) . '</span><input type="text" ' . ( $multi ? '' : 'id="jj" ' ) . 'name="jj" value="' . $jj . '" size="2" maxlength="2"' . $tab_index_attribute . ' autocomplete="off" /></label>';
$year = '<label><span class="screen-reader-text">' . __( 'Year' ) . '</span><input type="text" ' . ( $multi ? '' : 'id="aa" ' ) . 'name="aa" value="' . $aa . '" size="4" maxlength="4"' . $tab_index_attribute . ' autocomplete="off" /></label>';
$hour = '<label><span class="screen-reader-text">' . __( 'Hour' ) . '</span><input type="text" ' . ( $multi ? '' : 'id="hh" ' ) . 'name="hh" value="' . $hh . '" size="2" maxlength="2"' . $tab_index_attribute . ' autocomplete="off" /></label>';
$minute = '<label><span class="screen-reader-text">' . __( 'Minute' ) . '</span><input type="text" ' . ( $multi ? '' : 'id="mn" ' ) . 'name="mn" value="' . $mn . '" size="2" maxlength="2"' . $tab_index_attribute . ' autocomplete="off" /></label>';

echo '<div class="timestamp-wrap">';
/* translators: 1: month, 2: day, 3: year, 4: hour, 5: minute */
printf( __( '%1$s %2$s, %3$s @ %4$s:%5$s' ), $month, $day, $year, $hour, $minute );

echo '</div><input type="hidden" id="ss" name="ss" value="' . $ss . '" />';

if ( $multi ) return;

echo "\n\n";
$map = array(
'mm' => array( $mm, $cur_mm ),
'jj' => array( $jj, $cur_jj ),
'aa' => array( $aa, $cur_aa ),
'hh' => array( $hh, $cur_hh ),
'mn' => array( $mn, $cur_mn ),
);
foreach ( $map as $timeunit => $value ) {
list( $unit, $curr ) = $value;

echo '<input type="hidden" id="hidden_' . $timeunit . '" name="hidden_' . $timeunit . '" value="' . $unit . '" />' . "\n";
$cur_timeunit = 'cur_' . $timeunit;
echo '<input type="hidden" id="' . $cur_timeunit . '" name="' . $cur_timeunit . '" value="' . $curr . '" />' . "\n";
}
?>

Answer 2

以下のページが参考になりませんでしょうか。

JavaScriptのDateの挙動（Safari） - Qiita

【追記】

JavaScript の Date は罠が多くて専用のライブラリを使っている人もいます。

• JavaScript dayjsはMoment.jsの代替になるか? | nansystem
• 日付時刻操作ライブラリをmomentからdayjsへ乗り換えた - Qiita

JavaScriptの日付操作には罠が多く、業務では日付操作を簡単かつ安全に操作するライブラリが使われる。