Stability issues with GP5 to AlphaTex round-trip (Errors 209 & 218)

[LIUBINfighter]

Is there an existing issue for this?

• I have searched the existing issues, Broken percussion articulations for some GP5 files #2538 for error code 209

Discription

I am developing an alphaTex editor, Tabst. I encountered issues when importing GP files and converting them to alphaTex.

Debugging these issues directly within my complex Electron project was difficult, so I created a clean, standalone environment to stress-test the exporter using about 80 GP5 files. I performed a round-trip test (GP5 -> alphaTex -> Import alphaTex) to validate the stability.

Here are the specific semantic errors I found:

(Fixed) 1. Code AT209 — Percussion articulation: Unexpected percussion articulation value 'unknown'

Semantic error.
Appears 256 times across 18 files.
Cause: exported alphaTex contains an articulation value unknown that the importer does not accept.

2. Code AT218 — Note kind mismatch: Wrong note kind 'Fretted' for staff with note kind 'Articulation'

Semantic error.
Appears 109 times across 14 files.
Cause: notes marked as Fretted (guitar) are placed on an Articulation staff or otherwise produce incompatible staff/note kinds.

Steps To Reproduce

I have created a dedicated repository to reproduce these results: https://github.com/LIUBINfighter/AlexMi-Ha_GuitarTabs

1. Clone the repository above.
2. Run the included script (e.g., npm install, they were writen in readme.md).
3. The script transforms GP5 files (sourced from AlexMi-Ha/GuitarTabs) into alphaTex and attempts to re-import them.
4. Failing cases are recorded in the output.

Plateform

Web

Anything else?

in alphaTab 1.8.1, what causes code AT209 is fixed.

(Next time I will issue rather than a discusion for this kind of problem and using template. I was not sure if the gp files are broken or something else that time. Thanks! ：)

[Danielku15]

Please report bugs really as bugs in the issue tracker using the template 😉 I think in this case it's obvious that this is not an intended special behavior but really something is broken 😉

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I added #2538 this time to get things rolling for 1.8.1. I think this issue should describe the root cause and fix the problem.