Fix for RedHat 8 (env vars that are functions)

[javierggt]

Description

This is a fix for #25. In the end it is easy.

The source of the problem is that there are multi-line environmental variables (functions, actually), and the "parsing" of the environment wrongly matches lines within these multi-line variables as if they were variable definitions.

printenv indents the contents of these functions (the inner-scope lines start with a space). A normal variable definition does not start with space. Therefore, the solution is to ignore lines starting with space.

That is: replace re.search(..., s.strip()) by re.match(..., s.rstrip())

Fixes #25

Interface impacts

None

Testing

When doing tests, verified that tests pass in this PR and fail in master.

Unit tests

• Linux (rh8)

Independent check of unit tests by @taldcroft

• Mac
• Linux (CentOS-7, kady)

Functional tests

tried the specific test in #25:

from Ska.Shell import getenv, bash, run_shell
envs = getenv('export TEST_ENV_VARA="hello"')
bash('echo $TEST_ENV_VARA', env=envs)

@taldcroft also confirmed this functional test on han8-v (RH8) and kady (CentOS-7)

[taldcroft]

Awesome!

[taldcroft]

I did independent checks and all looks good.

[jeanconn]

It looks like this fix isn't actually needed on owen-v, but still seems fine.