Extension fails to launch with `IndexError: tuple index out of range`

[eloyrobillard]

Problem description

Please describe the issue concisely in here. In case of an error: Walk us through the steps you took to get there. What happened? What did you expect to happen?

Extension fails to start when launching Anki.

This is linked to a PR on the original extension: glutanimate/syntax-highlighting#42

To add some context: checking pygments' Available Lexers we can see that lexers like JsonBareObjectLexer do not have a "Short names" field (called aliases in the code).

Because of this we get the error shown below.

Checklist

Please replace the space inside the brackets with an x if the following items apply:

• I've restarted Anki to see if it helps
• I've verified that I use the latest version of the add-on by redownloading it from AnkiWeb
• I've verified that I use the latest version of Anki by checking at https://apps.ankiweb.net#download
• I've tried to disable other add-ons to see if there are any interactions present
• My issue disappears when I hold shift while starting Anki.
• I've checked if anyone else reported this problem before by looking through the issue reports. I also checked to see if there is a section about known issues in the add-on description, documentation, or README.

Information about your Anki set-up

Anki 23.12.1

Error message (if any)

Anki 23.12.1 (1a1d4d54)  (ao)
Python 3.9.15 Qt 6.5.3 PyQt 6.5.3
Platform: macOS-14.0-arm64-arm-64bit

When loading Syntax Highlighting NG:
Traceback (most recent call last):
  File "aqt.addons", line 245, in loadAddons
  File "/Users/eloy/Library/Application Support/Anki2/addons21/566351439/__init__.py", line 24, in <module>
    from . import main  # noqa: F401
  File "/Users/eloy/Library/Application Support/Anki2/addons21/566351439/main.py", line 52, in <module>
    LANGUAGES_MAP = {lex[0]: lex[1][0] for lex in get_all_lexers()}
  File "/Users/eloy/Library/Application Support/Anki2/addons21/566351439/main.py", line 52, in <dictcomp>
    LANGUAGES_MAP = {lex[0]: lex[1][0] for lex in get_all_lexers()}
IndexError: tuple index out of range

[cav71]

I wrote a PR in #2 that should fix it.

Can you please try to use the artifact built in https://github.com/cav71/syntax-highlighting-ng/actions/runs/7662328847 ?
If this works, I'll upload a new addon version.
Thanks

[eloyrobillard]

Thank you for your reply! 🙇
I got the following error when running the artifact:

Anki 23.12.1 (1a1d4d54)  (ao)
Python 3.9.15 Qt 6.5.3 PyQt 6.5.3
Platform: macOS-14.0-arm64-arm-64bit

When loading Syntax Highlighting (NG):
Traceback (most recent call last):
  File "aqt.addons", line 245, in loadAddons
  File "/Users/eloy/Library/Application Support/Anki2/addons21/syntax_highlighting_ng/__init__.py", line 24, in <module>
    from . import main  # noqa: F401
  File "/Users/eloy/Library/Application Support/Anki2/addons21/syntax_highlighting_ng/main.py", line 54, in <module>
    LANGUAGES_MAP = {lex[0]: lex[1][0] for lex in get_all_lexers() if len(lex) > 1}
  File "/Users/eloy/Library/Application Support/Anki2/addons21/syntax_highlighting_ng/main.py", line 54, in <dictcomp>
    LANGUAGES_MAP = {lex[0]: lex[1][0] for lex in get_all_lexers() if len(lex) > 1}
IndexError: tuple index out of range

While experimenting, the following worked for me:

{lex[0]: lex[1][0] for lex in get_all_lexers() if len(lex[1])}

So it looks like only the length of lex[1] (aliases) was a problem in my case.
But keeping len(lex) > 1 too is probably safer.

[cav71]

Thanks! I'm making changes latest addon build

[eloyrobillard]

👍 the latest build works

[cav71]

Just published the latest fix https://ankiweb.net/shared/info/566351439