Empty error panel when no arg help is shown with click 8.2.1 and typer 0.16.0

[DHUKK]

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 

app = typer.Typer(no_args_is_help=True)

@app.command()
def foo():
    ...

@app.command()
def bar():
    ...

if __name__ == "__main__":
    app()

Description

• install deps

click==8.2.1
markdown-it-py==3.0.0
mdurl==0.1.2
Pygments==2.19.1
rich==14.0.0
shellingham==1.5.4
typer==0.16.0
typing_extensions==4.13.2

• run python test.py (using the supplied code)
• the help panel will be shown but the command will exit with error code 2 and a blank error panel will be shown
• The command should exit with code 0 and the error panel should not be shown

Operating System

macOS

Operating System Details

Version 15.5

Typer Version

0.16.0

Python Version

Python 3.12.10

Additional Context

PR that added support (#1222) seems to have removed an assert on the exit code of a no args help here

[dylankiss]

I encountered exactly the same issue after upgrading to Typer 0.16.0. Version 0.15.4 (with Click < 8.2) was working fine.

[kandji-trent]

This issue appears to have been introduced in version 0.16.0 with click 8.2 support.

< 0.16.0

❯ cat test.py
#!/usr/bin/env -S uv run --python 3.13 --script
# /// script
# dependencies = [
#   "click<8.2.0",
#   "typer<0.16.0"
# ]
# ///

import typer

app = typer.Typer()


@app.command(no_args_is_help=True)
def main(greet: str) -> None:
    print(f"Hi, {greet}")


if __name__ == "__main__":
    app()
❯ ./test.py
Uninstalled 2 packages in 5ms
Installed 2 packages in 4ms

 Usage: test.py [OPTIONS] GREET

╭─ Arguments ──────────────────────────────────────────────────────────────────╮
│ *    greet      TEXT  [default: None] [required]                             │
╰──────────────────────────────────────────────────────────────────────────────╯
╭─ Options ────────────────────────────────────────────────────────────────────╮
│ --install-completion          Install completion for the current shell.      │
│ --show-completion             Show completion for the current shell, to copy │
│                               it or customize the installation.              │
│ --help                        Show this message and exit.                    │
╰──────────────────────────────────────────────────────────────────────────────╯

❯ echo $?
0

== 0.16.0

❯ cat test.py
#!/usr/bin/env -S uv run --python 3.13 --script
# /// script
# dependencies = [
#   "click==8.2.0",
#   "typer==0.16.0"
# ]
# ///

import typer

app = typer.Typer()


@app.command(no_args_is_help=True)
def main(greet: str) -> None:
    print(f"Hi, {greet}")


if __name__ == "__main__":
    app()
❯ ./test.py
Uninstalled 1 package in 3ms
Installed 1 package in 1ms

 Usage: test.py [OPTIONS] GREET

╭─ Arguments ──────────────────────────────────────────────────────────────────╮
│ *    greet      TEXT  [default: None] [required]                             │
╰──────────────────────────────────────────────────────────────────────────────╯
╭─ Options ────────────────────────────────────────────────────────────────────╮
│ --install-completion          Install completion for the current shell.      │
│ --show-completion             Show completion for the current shell, to copy │
│                               it or customize the installation.              │
│ --help                        Show this message and exit.                    │
╰──────────────────────────────────────────────────────────────────────────────╯
Usage: test.py [OPTIONS] GREET
Try 'test.py --help' for help.
╭─ Error ──────────────────────────────────────────────────────────────────────╮
│                                                                              │
╰──────────────────────────────────────────────────────────────────────────────╯
❯ echo $?
2

[zhu0629]

@tiangolo can you please check for this issue? Sir

[Fabian665]

@tiangolo it seems to be a problem related to this commit on click: pallets/click@d8763b9

This commit introduced an exception named NoArgsIsHelpError which is raised when no args are supplied to to script and no_args_is_help=True.

click == 8.1.8

    def parse_args(self, ctx: Context, args: list[str]) -> list[str]:
        if not args and self.no_args_is_help and not ctx.resilient_parsing:
            echo(ctx.get_help(), color=ctx.color)
            ctx.exit()

click >= 8.2.0

    def parse_args(self, ctx: Context, args: list[str]) -> list[str]:
        if not args and self.no_args_is_help and not ctx.resilient_parsing:
            raise NoArgsIsHelpError(ctx)

I have made a pull request that fixes that issue here #1240

[ncoghlan]

@SeedyROM also posted an interim workaround to the PR thread at #1240 (comment):

# Disable no_args_is_help, and specify the following callback logic instead
@app.callback(invoke_without_command=True)
def main(ctx: typer.Context):
    """My awesome CLI tool"""
    if ctx.invoked_subcommand is None:
        print(ctx.get_help())
        raise typer.Exit()

[svlandeg]

Thanks all!

This has been fixed by PR #1278 and released as Typer v.0.16.1.
The issue (only) happened when using Click 8.2.0 or higher.