Source

File: wp-includes/link-template.php

function edit_comment_link( $text = null, $before = '', $after = '' ) {
	$comment = get_comment();

	if ( ! current_user_can( 'edit_comment', $comment->comment_ID ) ) {
		return;
	}

	if ( null === $text ) {
		$text = __( 'Edit This' );
	}

	$link = '<a class="comment-edit-link" href="' . esc_url( get_edit_comment_link( $comment ) ) . '">' . $text . '</a>';

	/**
	 * Filters the comment edit link anchor tag.
	 *
	 * @since 2.3.0
	 *
	 * @param string $link       Anchor tag for the edit link.
	 * @param int    $comment_id Comment ID.
	 * @param string $text       Anchor text.
	 */
	echo $before . apply_filters( 'edit_comment_link', $link, $comment->comment_ID, $text ) . $after;
}