4-line Usage: when using Literal type

[pjonsson]

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 from typing import Literal, get_args # Does not work: # type ALL_PRODUCT_TYPES_T = Literal[ ALL_PRODUCT_TYPES_T = Literal[ "Longlonglongname1:more_long_things_here", "Longname2:NUM1ABC", "Longname2:NUM1ABC_delete", "Longname2:NUM2ABC", "Longname2:NUM2ABC_delete", "Longname3:NU_3_ABC___", "Longname3:NU_2_CDE___", "Longname3:NU_2_CDE____delete", ] ALL_PRODUCT_TYPES: tuple[ALL_PRODUCT_TYPES_T, ...] = get_args(ALL_PRODUCT_TYPES_T) app = typer.Typer() @app.command() def main( product_type: ALL_PRODUCT_TYPES_T = typer.Argument(...), # Type should really be list[ALL_PRODUCT_TYPES_T]. more_products: list[str] = typer.Argument(..., help=" ".join(ALL_PRODUCT_TYPES)) ) -> None: pass if __name__ == "__main__": app()

Description

I find the help text from the new Literal support quite hard to read, here's the output from the attached reproducer:

$ uv run ./test.py --help Usage: test.py [OPTIONS] PRODUCT_TYPE:{Longlonglongname1:more_long_things|Long name2:NUM1ABC|Longname2:NUM1ABC_delete|Longname2:NUM2ABC|Longna me2:NUM2ABC_delete|Longname3:NU_3_ABC___|Longname3:NU_2_CDE___| Longname3:NU_2_CDE____delete} MORE_PRODUCTS... ╭─ Arguments ──────────────────────────────────────────────────────────────────╮ │ * product_type PRODUCT_TYPE:{Longlonglo [required] │ │ ngname1:more_long_things │ │ |Longname2:NUM1ABC|Longn │ │ ame2:NUM1ABC_delete|Long │ │ name2:NUM2ABC|Longname2: │ │ NUM2ABC_delete|Longname3 │ │ :NU_3_ABC___|Longname3:N │ │ U_2_CDE___|Longname3:NU_ │ │ 2_CDE____delete} │ │ * more_products MORE_PRODUCTS... Longlonglongname1:more_lo… │ │ Longname2:NUM1ABC, │ │ Longname2:NUM1ABC_delete, │ │ Longname2:NUM2ABC, │ │ Longname2:NUM2ABC_delete, │ │ Longname3:NU_3_ABC___, │ │ Longname3:NU_2_CDE___, │ │ Longname3:NU_2_CDE____del… │ 

I think the 4 line Usage: is worse than the non-literal version that I've been using so far (passing help=str(['Longlonglongname1:more_long_things', ...]) to typer.Argument):

 Usage: cli.py [OPTIONS] PRODUCT_TYPE NAME ╭─ Arguments ──────────────────────────────────────────────────────────────────╮ │ * product_type TEXT ('Longlonglongname1:more_long_things', │ │ 'Longname2:NUM1ABC', │ │ 'Longname2:NUM1ABC_delete', │ │ 'Longname2:NUM2ABC', │ │ 'Longname2:NUM2ABC_delete', │ │ 'Longname3:NU_3_ABC___', │ │ 'Longname3:NU_2_CDE___', │ │ 'Longname3:NU_2_CDE____delete') │ │ [required] │ 

Is there some toggle to avoid making a multi-line Usage-line or similar?

I also get a failure in Typer if I use type ALL_PRODUCT_TYPES_T = Literal[... when defining the type for some reason (using the 3.12 syntax for type aliases requires changing the RHS of ALL_PRODUCT_TYPES to get_args(ALL_PRODUCT_TYPES_T.__value__), but that is unrelated to Typer), is that intentional?

Operating System

Linux

Operating System Details

No response

Typer Version

0.19.2

Python Version

3.12

Additional Context

No response

[YuriiMotov]

You can configure Usage using metavar parameter:

import typer from typing import Literal, get_args ALL_PRODUCT_TYPES_T = Literal[ "Longlonglongname1:more_long_things_here", "Longname2:NUM1ABC", "Longname2:NUM1ABC_delete", "Longname2:NUM2ABC", "Longname2:NUM2ABC_delete", "Longname3:NU_3_ABC___", "Longname3:NU_2_CDE___", "Longname3:NU_2_CDE____delete", ] app = typer.Typer() def get_help_for_literal(literal_type: type) -> str: values = get_args(literal_type) return "\n\n".join(f"'{value}'" for value in values) @app.command() def main( product_type: ALL_PRODUCT_TYPES_T = typer.Argument( ..., metavar="PRODUCT_TYPE", help=get_help_for_literal(ALL_PRODUCT_TYPES_T) ), ) -> None: pass if __name__ == "__main__": app()

Result:

$ typer main.py run --help Usage: typer [PATH_OR_MODULE] run [OPTIONS] PRODUCT_TYPE Run the provided Typer app. ╭─ Arguments ───────────────────────────────────────────────────────────────────────────────────╮ │ * product_type CHOICE 'Longlonglongname1:more_long_things_here' [required] │ │ 'Longname2:NUM1ABC' │ │ 'Longname2:NUM1ABC_delete' │ │ 'Longname2:NUM2ABC' │ │ 'Longname2:NUM2ABC_delete' │ │ 'Longname3:NU_3_ABC___' │ │ 'Longname3:NU_2_CDE___' │ │ 'Longname3:NU_2_CDE____delete' │ ╰───────────────────────────────────────────────────────────────────────────────────────────────╯ ╭─ Options ─────────────────────────────────────────────────────────────────────────────────────╮ │ --help Show this message and exit. │ ╰───────────────────────────────────────────────────────────────────────────────────────────────╯ 

As for type ALL_PRODUCT_TYPES_T = Literal[... syntax - it's not supported yet. Let's use the following discussion to track that: #971