Migrate some of the AMP [soundcloud] shortcode conversion to J… (#14028)

* Migrate some of the AMP [soundcloud] shortcode handling to Jetpack

The AMP plugin allows more $url values.
For example, it allows:
[soundcloud https://soundcloud.com/bonifansius/example-track]
Whereas Jetpack's non-AMP handling only allows
[souncloud url=<url here>].
@see https://github.com/ampproject/amp-wp/blob/e798258c22c465d60b4bd259f31d32c52817d6c7/includes/embeds/class-amp-soundcloud-embed.php#L128

* Copy a comment from the AMP plugin to this

This is important to explain
where the conversion will happen.

* Commit Jeremy's suggestion to check for the URL being empty

Co-Authored-By: Jeremy Herve <jeremy@tagada.hu>

* Add a unit test for the AMP [soundcloud] logic

This should run only if it's an AMP endpoint,
and if the URL is not empty().

* Skip this test on wp.com environments, copying Jeremy's snippet

Use Jeremy's snippet that we've used on
other shortcode PRs.

Author: kienstra

modules/shortcodes/soundcloud.php

@@ -30,6 +30,7 @@
  * @return string                  Widget embed code HTML
  */
 function soundcloud_shortcode( $atts, $content = null ) {
+	global $wp_embed;
 
 	// Custom shortcode options.
 	$shortcode_options = array_merge(
@@ -109,7 +110,17 @@ function soundcloud_shortcode( $atts, $content = null ) {
 		$options['visual'] = false;
 	}
 
-	// Build our list of Souncloud parameters.
+	if (
+		class_exists( 'Jetpack_AMP_Support' )
+		&& Jetpack_AMP_Support::is_amp_request()
+		&& ! empty( $options['url'] )
+		&& 'api.soundcloud.com' !== wp_parse_url( $options['url'], PHP_URL_HOST )
+	) {
+		// Defer to oEmbed if an oEmbeddable URL is provided.
+		return $wp_embed->shortcode( $options, $options['url'] );
+	}
+
+	// Build our list of Soundcloud parameters.
 	$query_args = array(
 		'url' => rawurlencode( $options['url'] ),
 	);

tests/php/modules/shortcodes/test-class.soundcloud.php

@@ -116,4 +116,40 @@ public function test_shortcodes_soundcloud_reversal_embed() {
 
 		$this->assertEquals( $shortcode_content, '<a href="https://player.soundcloud.com/player.swf?url=http://api.soundcloud.com/tracks/70198773">https://player.soundcloud.com/player.swf?url=http://api.soundcloud.com/tracks/70198773</a>' );
 	}
+
+	/**
+	 * Tests the shortcode output on an AMP endpoint.
+	 *
+	 * @covers ::soundcloud_shortcode
+	 * @since 8.0.0
+	 */
+	public function tests_shortcodes_soundcloud_amp() {
+		if ( defined( 'IS_WPCOM' ) && IS_WPCOM ) {
+			self::markTestSkipped( 'WordPress.com does not run the latest version of the AMP plugin yet.' );
+			return;
+		}
+
+		// Simulate the oEmbed filter in the AMP plugin that should run on calling $wp_embed->shortcode().
+		$oembed_markup = '<amp-soundcloud></amp-soundcloud>';
+		add_filter(
+			'embed_oembed_html',
+			static function( $cache ) use ( $oembed_markup ) {
+				unset( $cache );
+				return $oembed_markup;
+			}
+		);
+
+		$content_with_url       = '[soundcloud url="https://soundcloud.com/necmusic/mozart-concerto-for-piano-no-2"]';
+		$content_with_empty_url = '[soundcloud url=""]';
+
+		// If the URL is empty, the AMP logic should not run.
+		$this->assertNotContains( $oembed_markup, do_shortcode( $content_with_empty_url ) );
+
+		// This is still not an AMP endpoint, so the AMP logic should not run.
+		$this->assertNotContains( $oembed_markup, do_shortcode( $content_with_url ) );
+
+		// Now that this is an AMP endpoint with a URL value, the AMP logic should run.
+		add_filter( 'jetpack_is_amp_request', '__return_true' );
+		$this->assertEquals( $oembed_markup, do_shortcode( $content_with_url ) );
+	}
 }