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AmbiguousEnvVar when setting default runner.env with both lower and uppercase

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#932 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
cli

Research direction

Reproduce the failure using invoke.yml and tasks.py, or the Python configuration shown, then run the @invoke.task function through ctx.run('env && exit 1'). Trace the environment handling involved in RUN_ENV_NO_PROXY and verify that configuring both uppercase and lowercase variants no longer raises AmbiguousEnvVar while preserving the configured values.

Written by the indexing model from the issue text.

Description

Hi,

I think I discovered an issue with the environment system, you can't set default environment variables with both upper and lowercase variants, like for HTTP_PROXY:

import invoke

ns = invoke.Collection()
ns.configure(dict(
    run=dict(
        echo=True,
        env={
            **{
                env_name: "http://my-proxy/"
                for env_name in ("http_proxy", "https_proxy", "HTTP_PROXY", "HTTPS_PROXY")
            },
            **{
                env_name: "localhost" for env_name in ("no_proxy", "NO_PROXY")
            }
        }
    )
))

@invoke.task
def test(ctx):
    ctx.run('env && exit 1')

ns.add_task(test, "test")

This is also true with the following:

invoke.yml

run:
  env:
    HTTP_PROXY: 1
    http_proxy: 1

tasks.py

import invoke

@invoke.task
def test(ctx):
    ctx.run('env && exit 1')

inv test
[..]
invoke.exceptions.AmbiguousEnvVar: Found >1 source for RUN_ENV_NO_PROXY

I guess only keys with the invoke prefix or only external (not set in config) environment variables should be analyzed? RUN_ENV_ subkeys should be analyzed without case modification?

Dominant language
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