sneaky edge case for comments in plaintext

src/indieweb/comments.php

@@ -257,7 +257,9 @@ function parse($mf, $refURL=false, $maxTextLength=150, $maxLines=2) {
         if($nameSanitized != $contentSanitized and $nameSanitized !== '') {
           // If the name is the beginning of the content, we don't care
           // Same if the content is the beginning of the name (like with really long notes)
-          if(!(strpos($contentSanitized, $nameSanitized) === 0) && !(strpos($nameSanitized, $contentSanitized) === 0)) {
+          if($contentSanitized === '' 
+            || (!(strpos($contentSanitized, $nameSanitized) === 0) && !(strpos($nameSanitized, $contentSanitized) === 0))
+            ) {
             // The name was determined to be different from the content, so return it
             $name = $properties['name'][0]; //truncate($properties['name'][0], $maxTextLength, $maxLines);
           }

tests/BasicTest.php

@@ -281,6 +281,32 @@ public function testBnvk() {
 \t\tMar 30, 2014", $result['text']);
   }
 
+  public function testMentionNoNameWithContent() {
+    $result = IndieWeb\comments\parse($this->buildHEntry(array(
+      'name' => '',
+      'content' => 'post name'
+    )), false, 90);
+    $this->assertEquals('mention', $result['type']);
+    $this->assertEquals('', $result['name']);
+    $this->assertEquals('post name', $result['text']);
+  }
+
+  public function testMentionCommentedContentWithName() {
+    // It's possible for the plaintext to end up with an HTML comment for various reasons.
+    // Version 0.2.* of php-mf2 failed to remove the contents of <script> tags from plaintext,
+    // so you could end up with <script><!-- foo --></script> leading to an HTML comment in the text.
+    // Also <div class="e-content">&lt;!-- Hello World --></div> will result in what looks like HTML comment in the value.
+    $result = IndieWeb\comments\parse($this->buildHEntry(array(
+      'name' => "post name",
+      'content' => [
+        'html' => "<p><!-- comment --></p>",
+        'value' => "<!-- comment -->"
+      ]
+    )), false, 500);
+    $this->assertEquals('mention', $result['type']);
+    $this->assertEquals('post name', $result['name']);
+  }
+
   /***************************************************************************
    * Other post types
    */