adds a Regex to make sure audio tag gets both start and end tags

Author: mzorz

wordpress-shortcodes/src/main/java/org/wordpress/aztec/plugins/shortcodes/AudioShortcodePlugin.kt

@@ -14,7 +14,13 @@ class AudioShortcodePlugin : IHtmlPreprocessor, IHtmlPostprocessor {
     }
 
     override fun onHtmlProcessed(source: String): String {
-        if (GutenbergUtils.contentContainsGutenbergBlocks(source)) return source
+        if (GutenbergUtils.contentContainsGutenbergBlocks(source)) {
+            // From https://developer.mozilla.org/en-US/docs/Web/HTML/Element/audio
+            // > Tag omission	None, both the starting and ending tag are mandatory.
+            return StringBuilder(source)
+                    .replace(Regex("(<$TAG[^>]*?)(\\s*/>)"), "\$1></$TAG>")
+        }
+
         return StringBuilder(source)
                 .replace(Regex("<$TAG([^>]*(?<! )) */>"), "[$TAG$1]")
                 .replace(Regex("<$TAG([^>]*(?<! )) *></$TAG>"), "[$TAG$1]")

wordpress-shortcodes/src/test/java/org/wordpress/aztec/plugins/shortcodes/AudioShortcodeTest.kt

@@ -51,7 +51,7 @@ class AudioShortcodeTest {
 
         // expected result: the <audio> tag does not get converted to shortcode when it's found within a Gutenberg block
         // Note: the slight difference of <audio controls> being converted to <audio controls="controls"> should be equivalent
-        val htmlWithoutShortcode = "<!-- wp:audio {\"id\":435} --><figure class=\"wp-block-audio\"><audio controls=\"controls\" src=\"https://selfhostedmario.mystagingwebsite.com/wp-content/uploads/2018/05/ArgentinaAnthem.mp3\" /><figcaption>a caption</figcaption></figure><!-- /wp:audio -->"
+        val htmlWithoutShortcode = "<!-- wp:audio {\"id\":435} --><figure class=\"wp-block-audio\"><audio controls=\"controls\" src=\"https://selfhostedmario.mystagingwebsite.com/wp-content/uploads/2018/05/ArgentinaAnthem.mp3\"></audio><figcaption>a caption</figcaption></figure><!-- /wp:audio -->"
 
         Assert.assertEquals(htmlWithoutShortcode, editText.toPlainHtml())
     }