Inventory_Presser_Shortcode_Grid::content( array $atts )

	public function content( $atts ) {

		/**
		 * Shortcode attributes & default values. Some of these overlap to
		 * provide backwards compatibility with a time when this widget and the
		 * shortcode did not share any code. (Widget? What? See comment below.)
		 */
		$new_atts = shortcode_atts(
			array(

				/*
					Old attributes
					----------
					'per_page'   15
					'captions'   true,
					'button'     true,
					'show_price' false,
					'size'       'one-third',
				*/

				'columns'       => 3, // replaces 'size'.
				'featured_only' => false,
				'limit'         => 15, // replaces 'per_page'.
				'newest_first'  => false,
				'show_button'   => true, // replaces 'button'.
				'show_captions' => false, // replaces 'captions'.
				'show_prices'   => false, // replaces 'show_price'.
			),
			$atts
		);

		// Handle the old attribute names.
		if ( isset( $atts['per_page'] ) && ! isset( $atts['limit'] ) ) {
			$atts['limit'] = $atts['per_page'];
		}
		if ( isset( $atts['captions'] ) && ! isset( $atts['show_captions'] ) ) {
			$new_atts['show_captions'] = $atts['captions'];
		}
		if ( isset( $atts['button'] ) && ! isset( $atts['show_button'] ) ) {
			$new_atts['show_button'] = $atts['button'];
		}
		if ( isset( $atts['show_price'] ) && ! isset( $atts['show_prices'] ) ) {
			$new_atts['show_prices'] = $atts['show_price'];
		}
		if ( isset( $atts['size'] ) && ! isset( $atts['columns'] ) ) {
			switch ( $atts['size'] ) {
				case 'one-third':
					$new_atts['columns'] = 3;
					break;
				case 'one-fourth':
					$new_atts['columns'] = 4;
					break;
				case 'one-fifth':
					$new_atts['columns'] = 5;
					break;
			}
		}

		/**
		 * We actually use the Grid widget to generate the output of this
		 * shortcode since version 10.1.0. The output was very similiar but
		 * the arguments didn't overlap completely before that, so they were
		 * merged to make life easy.
		 */
		$widget = new Inventory_Presser_Grid();
		return $widget->content( $new_atts );
	}