Fix Message Components for Tags with Attributes

Don't assume that the close tag is the length of the start tag +1

BUG: 482331

autotests/texthandlertest.cpp

@@ -529,6 +529,19 @@ void TextHandlerTest::componentOutput_data()
     QTest::newRow("inline code single block") << QStringLiteral("<code>https://kde.org</code>")
                                               << QList<MessageComponent>{
                                                      MessageComponent{MessageComponentType::Text, QStringLiteral("<code>https://kde.org</code>"), {}}};
+    QTest::newRow("long start tag")
+        << QStringLiteral(
+               "Ah, you mean something like<br/><pre data-md=\"```\"><code class=\"language-qml\"># main.qml\nimport CustomQml\n...\nControls.TextField { id: "
+               "someField }\nCustomQml {\n    someTextProperty: someField.text\n}\n</code></pre>Sure you can, it's still local to the same file where you "
+               "defined the id")
+        << QList<MessageComponent>{
+               MessageComponent{MessageComponentType::Text, QStringLiteral("Ah, you mean something like"), {}},
+               MessageComponent{
+                   MessageComponentType::Code,
+                   QStringLiteral(
+                       "# main.qml\nimport CustomQml\n...\nControls.TextField { id: someField }\nCustomQml {\n    someTextProperty: someField.text\n}"),
+                   QVariantMap{{QStringLiteral("class"), QStringLiteral("qml")}}},
+               MessageComponent{MessageComponentType::Text, QStringLiteral("Sure you can, it's still local to the same file where you defined the id"), {}}};
 }
 
 void TextHandlerTest::componentOutput()

src/texthandler.cpp

@@ -307,13 +307,14 @@ int TextHandler::nextBlockPos(const QString &string)
         return string.size();
     }
 
-    int closeTagPos = string.indexOf(QStringLiteral("</%1>").arg(tagType));
+    const auto closeTag = QStringLiteral("</%1>").arg(tagType);
+    int closeTagPos = string.indexOf(closeTag);
     // If the close tag can't be found assume malformed html and process as single block.
     if (closeTagPos == -1) {
         return string.size();
     }
 
-    return closeTagPos + tag.size() + 1;
+    return closeTagPos + closeTag.size();
 }
 
 MessageComponent TextHandler::nextBlock(const QString &string,