Eliminating undefined parameters entirely by `NeverUndefined`

[James4Ever0]

This pull request is done by changing two files in the source code directory. It integrates the NeverUndefined class and make it usable by:

import jinja2
# access by: jinja2.NeverUndefined

This will raise exception for the following template, while StrictUndefined will not:

{% macro test(a, b, c) %}
a macro with three parameters but not used
{% endmacro %}

{{ test() }}

• fixes #1923

Checklist:

• [x] Add tests that demonstrate the correct behavior of the change. Tests should fail without the change.
• [ ] Add or update relevant docs, in the docs folder and in code.
• [ ] Add an entry in CHANGES.rst summarizing the change and linking to the issue.
• [ ] Add .. versionchanged:: entries in any relevant code docs.
• [ ] Run pre-commit hooks and fix any issues.
• [ ] Run pytest and tox, no tests failed.

[ThiefMaster]

did you create the PR using an LLM? the code and comments in there surely look like that's the case...

You also don't explain when your code would actually be useful...

[James4Ever0]

did you create the PR using an LLM? the code and comments in there surely look like that's the case...

You also don't explain when your code would actually be useful...

This code is half a year old and I do it for fixing this long standing error.

I want to explain but my memory is fuzzy. It is useful.

About your suspicion, I can tell that I had the feeling too. I am building a project named Cybergod, which can control mouse and keyboard and possibly do stuffs like browsing Github, making pull requests :)

The comment in the code is to indicate what were passed as *args and **kwargs at that location. I reason about the *args are not so easy to be parsed, neither as the **kwargs.

I decide to collect the info from *args and **kwargs as error message, and raise Exception right after __init__, not waiting for invocation, unlike StrictUndefined.

[davidism]

See issue for slightly longer explanation. If you think this is generally useful to others, you can create an extension, but there's nothing requiring it to be in Jinja core.