BUG: Required arguments no longer yield errors with click 8.3.0

[linde12]

First Check

• I added a very descriptive title here.
• I used the GitHub search to find a similar question and didn't find it.
• I searched the Typer documentation, with the integrated search.
• I already searched in Google "How to X in Typer" and didn't find any information.
• I already read and followed all the tutorials in the docs and didn't find an answer.
• I already checked if it is not related to Typer but to Click.

Commit to Help

• I commit to help with one of those options 👆

Example Code

import typer


def main(name: str):
    print(f"Hello {name}")


if __name__ == "__main__":
    typer.run(main)

Description

• Create a virutal env with typer and add a main.py with the contents from above (taken from official docs)
• Verify that it does not error on required arguments, simply prints "Hello None", when run with python main.py
• Verify that if you explicitly install click 8.1.0, typer will output an error as expected, when run with python main.py
• Verify that it typer ignores that the argument is required when you explicitly install 8.3.0 (which will be installed by default when you install typer), when run with python main.py

Operating System

Linux

Operating System Details

No response

Typer Version

0.17.4 (but same issue verified many versions back)

Python Version

3.13.6

Additional Context

Seems like something broke with click 8.3.0. I've tried using click and it works as expected to me, so i do not believe it is an issue with click.

[linde12]

Click 8.3.0:

Click 8.1.0:

[linde12]

Corresponding CLI with only click 8.3.0 works:

[svlandeg]

Thanks for the report, I'm looking into this right now!

[acmiyaguchi]

I accidentally filed a bug with uv instead of looking into discussions here. I didn't realize at first glance what the issue was and didn't see that most of the bug reports were in discussion. astral-sh/uv#15946

[svlandeg]

PR that provides more background information and a potential fix: #1333

[svlandeg]

This is now fixed and released:

• Typer 0.17.5 restricts Click to below 8.3.0 (as a quick fix)
• Typer 0.18.0 allows Click 8.3.0 and fixes this bug