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@Narkunan I'm sorry, but this change is getting a bit harder. I hope you can understand what I'm asking for:

1. In the existing tests, the translation of _italics_ and __bold__ to HTML has changed from <i> / <em> to <em> / <strong>. It should be relatively easy to do, once you see it in code. Look at the tests 69a4165d-9bf8-4dd7-bfdc-536eaca80a6a, ec345a1d-db20-4569-a81a-172fe0cad8a1, 51164ed4-5641-4909-8fab-fbaa9d37d5a8, and 7bf92413-df8f-4de8-9184-b724f363c3da in canonical-data.json and adjust our test file accordingly. Of course, you also need to adjust the example file .meta/example.php and the student's file Markdown.php to make the tests pass again. This change already makes all existing solutions fail, but I think it is worth doing so.
2. The next challenge is to add the new tests and make them pass - which also breaks all solutions. This is not straight forward, as the code given to the students intentionally is bloated and convoluted.
   • First change the single quotes ' on the input values inside parseMarkdown() to double quotes ". In PHP the character sequence \n is not a LINEFEED when put into single quotes. It's best to have all parseMarkdown() invocations use the same quoting style, but at least tests 113a2e58-78de-4efa-90e9-20972224d759 and f0bbbbde-0f52-4c0c-99ec-be4c60126dd4 are required.
   • Then make the new tests pass. I have prepared the required changes to the student's and example files to fix the code but keep the ugliness. You are welcome to do that on your own!
3. As a last and optional step it makes sense to format all tests identically. Break all $this->assertEquals(); to multiple lines, as you did for the new tests already.

Well, yes, sorry again. I haven't seen all this when I classified the issue as "good first issue". That is a lot of exceptional stuff to do...

@mk-mxp I hope I addressed everything. Please check now 😊