parse poster attribute for video tags

if there is a poster attribute and no src attribute on a video tag, the poster attribute is used as the value instead.

This test won't pass until after #119 is merged to fix the other `getAttribute` issues.

Author: aaronpk

Mf2/Parser.php

@@ -615,6 +615,8 @@ public function parseU(\DOMElement $u) {
 			$uValue = $u->getAttribute('href');
 		} elseif (in_array($u->tagName, array('img', 'audio', 'video', 'source')) and $u->getAttribute('src') !== null) {
 			$uValue = $u->getAttribute('src');
+		} elseif ($u->tagName == 'video' and !$u->hasAttribute('src') and $u->hasAttribute('poster')) {
+			$uValue = $u->getAttribute('poster');
 		} elseif ($u->tagName == 'object' and $u->getAttribute('data') !== null) {
 			$uValue = $u->getAttribute('data');
 		}

tests/Mf2/ParseUTest.php

@@ -175,6 +175,19 @@ public function testParseUHandlesSource() {
 		$this->assertEquals('http://example.com/video.ogg', $output['items'][0]['properties']['video'][1]);
 	}
 
+	/**
+	 * @group parseU
+	 */
+	public function testParseUHandlesVideoPoster() {
+		$input = '<div class="h-entry"><video class="u-photo" poster="http://example.com/posterimage.jpg"><source class="u-video" src="http://example.com/video.mp4" type="video/mp4"></video></div>';
+		$parser = new Parser($input);
+		$output = $parser->parse();
+
+		$this->assertArrayHasKey('video', $output['items'][0]['properties']);
+		$this->assertEquals('http://example.com/video.mp4', $output['items'][0]['properties']['video'][0]);
+		$this->assertEquals('http://example.com/posterimage.jpg', $output['items'][0]['properties']['photo'][0]);
+	}
+
 	/**
 	 * @group parseU
 	 */