fix: coerce python version to semver

[radiantly]

To fix forwardemail/free-email-forwarding#134

[codecov-io]

Codecov Report

Merging #1 into master will increase coverage by 0.86%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master       #1      +/-   ##
==========================================
+ Coverage   80.95%   81.81%   +0.86%     
==========================================
  Files           1        1              
  Lines          21       22       +1     
==========================================
+ Hits           17       18       +1     
  Misses          4        4

Impacted Files	Coverage Δ
index.js	81.81% <100%> (+0.86%)	⬆️

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[niftylettuce]

@radiantly why did you add stdout here? python --version reports to stderr afaik for all versions.

[niftylettuce]

we'll also need to make the same PR/change in forwardemail/python-dkim-verify@c5db654

[radiantly]

I copied the format from python-dkim-verify, where the silent flag was set to false when testing.

const silent = process.env.NODE_ENV !== 'test';
const options = { silent, async: true };

// ensure python v2.7+ or v3.5+
let version = exec('python --version', { silent });
version = (version.stdout ? version.stdout : version.stderr)
  .split(' ')[1]
  .trim();

What do you think?

[radiantly]

@niftylettuce

[radiantly]

ping @niftylettuce see my comment above

[niftylettuce]

Actually, I like semver.coerce better. I've fixed this in both packages we use internally and also version bumped them. Thanks so much @radiantly for the nice fix.