Don't raise W006 warning when app loader is specified.

[tim-schilling]

Fixes #1550

Thank you @leon-matthews for the report!

[codecov]

Codecov Report

Merging #1556 (199eeb6) into main (66fe9c8) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1556      +/-   ##
==========================================
+ Coverage   86.62%   86.66%   +0.03%     
==========================================
  Files          36       36              
  Lines        1862     1867       +5     
  Branches      303      303              
==========================================
+ Hits         1613     1618       +5     
  Misses        175      175              
  Partials       74       74              

Impacted Files	Coverage Δ
debug_toolbar/apps.py	93.65% <100.00%> (+0.54%)	⬆️

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[matthiask]

Nice! A good side-effect of this is that it annoys people even more who use the toolbar with DEBUG=False.

[tim-schilling]

A good side-effect of this is that it annoys people even more who use the toolbar with DEBUG=False.

It does?

[matthiask]

A good side-effect of this is that it annoys people even more who use the toolbar with DEBUG=False.

It does?

Possibly, if they are using the old pattern of adding the cached Loader when DEBUG is falsy in the settings. Or not? Maybe I'm not thinking clearly (again).

[tim-schilling]

From my understanding, if the user specifies any loader, those are the loaders that are used. No additional loaders, including the cached loader will be used.

If they don't specify loaders, then Django will specify the filesystem loader, and if app_dirs is True, then the app loader. Then if debug is false it will use the cached loader with whichever are used.

Sorry, my brain isn't working at 100%. I'm probably being pedantic.

Edit: relevant code: https://github.com/django/django/blob/main/django/template/engine.py#L20-L32