fix case in which closing tag preceding opening tag acts as pair, creating negative length item to be flushed (#78)

Co-authored-by: Dominik Vašíček <dominik.vasicek@trayto.com>

Author: dominik-vasicek

src/XmlStringStreamer/Parser/UniqueNode.php

@@ -134,7 +134,7 @@ private function checkShortClosingTag($workingBlob, $len) {
      */
     protected function getClosingTagPos()
     {
-        $endPositionInBlob = strpos($this->workingBlob, "</" . $this->options["uniqueNode"] . ">");
+        $endPositionInBlob = strpos($this->workingBlob, "</" . $this->options["uniqueNode"] . ">", $this->startPos);
         if ($endPositionInBlob === false) {
 
             if (isset($this->options["checkShortClosing"]) && $this->options["checkShortClosing"] === true) {

tests/integration/XmlStringStreamer/XmlStringStreamerIntegrationTest.php

@@ -317,4 +317,26 @@ public function test_StringWalker_parser_reset_working_blob()
         $parser->reset();
         self::assertSame("\n    <item>0</item>", $streamer->getNode());
     }
+    
+    public function test_UniqueNode_parser_stream_seeking()
+    {
+        $filePath = __dir__ . '/../../xml/stream_seeking.xml';
+        $fileHandle = fopen($filePath, 'rb');
+        
+        $stream = new XmlStringStreamer\Stream\File($fileHandle, 50);
+        $parser = new UniqueNode(["uniqueNode" => 'item']);
+        $streamer = new XmlStringStreamer($parser, $stream);
+        
+        self::assertSame('<item>first item to read</item>', $streamer->getNode());
+        
+        /**
+         * @see /tests/xml/stream_seeking.xml
+         * hash character is used as seek target in file, creating case where closing tag precedes opening tag
+         */
+        $seekTargetPosition = strpos(file_get_contents($filePath), '#');
+        fseek($fileHandle, $seekTargetPosition);
+        $parser->reset();
+        
+        self::assertSame('<item>second item to read</item>', $streamer->getNode());
+    }
 }

tests/unit/XmlStringStreamer/Parser/UniqueNodeTest.php

@@ -263,4 +263,28 @@ public function test_multiple_roots()
             "When no nodes are left, false should be returned"
         );
     }
-}
+    
+    public function test_orphan_closing_tag_is_ignored()
+    {
+        $expectedStringToBeFlushed = '<child>read this</child>';
+        $xml = <<<eot
+<?xml version="1.0"?>
+<root>
+    </child>
+    $expectedStringToBeFlushed
+</root>
+eot;
+        
+        $stream = $this->getStreamMock($xml, strlen($xml));
+        
+        $parser = new UniqueNode([
+            "uniqueNode" => "child"
+        ]);
+        
+        $this->assertEquals(
+            $expectedStringToBeFlushed,
+            $parser->getNodeFrom($stream),
+            "Orphan closing tag must not act as closing tag for first opening tag"
+        );
+    }
+}

tests/xml/stream_seeking.xml

@@ -0,0 +1,5 @@
+<root>
+    <item>first item to read</item>
+    <item>seek will land before hash character: #</item>
+    <item>second item to read</item>
+</root>