Fix Cubase XML chord symbol import

[Jojo-Schmitz]

Follow up to #24915

Resolves: #24865 and https://musescore.org/en/node/368990#comment-1260723

[cbjeukendrup]

I wonder if a more general approach is needed, such as letting readInt always call .simplified. @miiizen what do you think?

[Jojo-Schmitz]

You mean like this?

int String::toInt(bool* ok, int base) const
{
    ByteArray ba = simplified().toUtf8();
    return static_cast<int>(toInt_helper(ba.constChar(), ok, base));
}

[cbjeukendrup]

I was actually thinking of something in XmlStreamReader::readInt. Note that AsciiStringView::toInt is used here, rather than String::toInt. Making the change directly at the String/AsciiStringView level may or may not be a good idea; I don't have a strong opinion about that.

Also, It may be better to use String::trimmed instead of simplified; trimmed only removes leading and trailing whitespace, while simplified simplifies all whitespace including mid-string. But if there was any mid-string whitespace, then toInt would fail anyway, so no reason to try to simplify that mid-string whitespace first.

[Jojo-Schmitz]

I'd prefer to use simplified() or maybe trimmed() in just those 2 locations in importmxmlpass2.cpp.

[cbjeukendrup]

But I think we can't assume that those are the only places where we will ever encounter leading/trailing whitespace. The XML specification says that whitespace around numbers is allowed and should be ignored by the parser. More precisely,

• This is the spec for the whiteSpace constraint: https://www.w3.org/TR/xmlschema-2/#rf-whiteSpace
• This is the spec for the decimal type, stating that it has the whiteSpace constraint applied: https://www.w3.org/TR/xmlschema-2/#decimal
• MusicXML inherits the decimal type from the XML schema standard: https://www.w3.org/2021/06/musicxml40/musicxml-reference/data-types/xsd-decimal/
• The semitones type in MusicXML is based on decimal: https://www.w3.org/2021/06/musicxml40/musicxml-reference/data-types/semitones/

[Jojo-Schmitz]

As per https://www.w3.org/2021/06/musicxml40/musicxml-reference/data-types/semitones/ that makes up for 5 occurences in in importmxmlpass2.cpp. Still pretty managable, to be done individually there. There are many more toInt() though, not listed there. I won't like to "disturb" those.

[cbjeukendrup]

But of course it does not only apply to the semitones type, but to basically all cases where a number has to be parsed from an XML tag's content. Hence my suggestion to make the change in XmlStreamReader::readInt.

[Jojo-Schmitz]

It'd also be readText().toInt()

[Jojo-Schmitz]

oops

[miiizen]

Yes, we should probably do this in XmlStreamReader - my only hesitation is that this code is more often used to read MuseScore files, which really shouldn't need this sanitisation. However, I doubt this will have a huge impact on performance

[Jojo-Schmitz]

As that uses AsciiStringView, this isn't really trivial

[miiizen]

I struggled to find a more general solution without incurring more overheads than necessary in the xml reader. I'd still prefer we fix this in XmlStreamReader, but I'm happy with this solution for the moment.

[Jojo-Schmitz]

Rebased to fix alleged but non-existent merge conflicts