Adding returns to command

[PCanavelli]

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Example Code

import random

import typer

from typer.testing import CliRunner

app = typer.Typer()

@app.command()
def main():
    result = random.random()

    return result

def test_app() -> None:
    runner = CliRunner()
    result = runner.invoke(app)

    assert result.return_value == 0

Description

Hi everyone,

I am trying to write some end-to-end tests for a typer command that affects the state of an object.

To so do, I was hoping to set up a unit test using CliRunner as per the documentation.

I was expecting the result of the invoke method to include the result returned by the invoked command.

However, try as I may, the return_value of the Result object stays None, regardless of whether the command returns something.

Is there a clean way to achieve what is described in the code snippet above?

Cheers

Operating System

Linux

Operating System Details

No response

Typer Version

0.9.0

Python Version

3.10.13

Additional Context

No response

[melsabagh]

Why not print the output then access it in result.output?

[lachaib]

When working with CLI, the return value is generally discarded. You can pass a return code using sys.exit or Typer's equivalent. That way you can assert on the exit code (result.exit_code), or print (or use Typer.echo) and assert on the output result.output as suggested by @melsabagh.
Outside of the scope of testing, where would you expect the return of the command to go to?