Incorrect Chord Parsing & Playback for Augmented/Diminished 7th Chords using "+"/"o" Symbol

• Aug 14, 2020 - 17:33
Reported version
3.5
Type
Functional
Frequency
Few
Severity
S5 - Suggestion
Reproducibility
Always
Status
closed
Regression
No
Workaround
Yes
Project

When using the "+" symbol to notate an Dominant 7th chord with an augmented triad, placing the "+" symbol after the 7 causing incorrect chord parsing & playback. For example C7+ versus C+7.

When the chord is notated as C7+, it plays back only the root and is parsed incorrectly when viewed using the Realize Chord Symbol tool.

Other chord symbols using other modifiers such as C9+ playback correctly and are parsed accurately.

Placement of the "+" AFTER the 7 or other modifier is very common in published scores and should work in MuseScore as it does with 9ths, 11ths, etc.


Comments

Title Incorrect Chord Parsing & Playback for Augmented 7th Chords using "+" Symbol Incorrect Chord Parsing & Playback for Augmented/Diminished 7th Chords using "+"/"o" Symbol

These are actually two very different issues in terms of the implementation. C7+ we do handle, at least partially, and get the right MusicXML at one point, but then don't realize we've handled it and end up marking the score not understandable. C9+ doesn't need the special MusicXML handling, so that we get right. This is an extremely easy fix, and worth it because this is not that uncommon of a way to write chords.

C7o we just don't even try to handle, because I had never seen it before when I wrote the parsing code. So we'd have to implement special handling for that. No doubt it's doable but rather more difficult, and as far as I know the number of people using this particular spelling is probably very small in comparison.

So I might propose a quick fix just for C7+ but still leave an open issue for C7o.

Status PR created fixed

Fixed in branch 3.x, commit 51289cb40d

_fix #309108: add support for quality after extension

The chord symbol parser was implemented many years ago
and it supports msot common notations, but a few used in some regions
slipped through the track. In particular, C7o and C7+.
These place the quality after the extension.
There was partial support for C7+, and it parsed OK,
but a bug never noticed until now is that it was also marked
as not "understandable", which now prevents playback.

This commit fixes the bug that prevented C7+ from fully working,
but adding a null handler for an empty token in the loop
during which the "+" is processed and replaced with an empty token.
It also adds the same processing for C7o._

Fix version
3.5.1