Hard line breaks always also add newline about prosemirror-markdown

[marijnh]

I don't quite understand the problem here. If I add a test for the document you show (in attached patch), that content seems to round-trip just fine, without any extra newlines being inserted.

[susnux]

I don't quite understand the problem here

It does not happen when using the provided markdown parser, but if happens if you set the parse options / parse rules of paragraphs to preserveWhitespace: true.

e.g. you want to keep the formatting of a markdown file after a roundtrip you need to keep any additional tabs and spaces and also newlines "soft brakes" like:

hello
world

should stay like this after a roundtrip and not result in

hello world

even if this is syntactically the same.

So the previous example results in:

<p>hello<br />
world</p>

which is this prosemirror state: doc(p("hello", br(), "\nworld")).

And that state would currently be serialized as

hello\

world

(note the additional newline).

See the testcase in the PR:

serialize(doc(p(em("foo", br(), "\nbar"))), "*foo\\\nbar*")

[marijnh]

It does not happen when using the provided markdown parser, but if happens if you set the parse options / parse rules of paragraphs to preserveWhitespace: true.

That's a DOM parser option, though. How does that effect Markdown deserializing?

[susnux]

As I said I do not use the provided parser, but plain markdown-it as the project uses quite a lot markdown extensions.

So this is only a problem if you use the to_markdown part of this nice project together with custom markdown parsing.
(I can understand if you decide that this is a won't fix)

[marijnh]

Ah, all right. I think this is something you'll have to address in your custom parser then.