Simplify Matrix decode, add defaults for fail-fast and max-parallel, add test

[catthehacker]

fix[workflow]: default max-parallel
fix[workflow]: default fail-fast, it's true, not false
fix[workflow]: skipping over the job when strategy: is defined but matrix: isn't (fixes #625)
fix[workflow]: skip non-existing includes keys and hard fail on non-existing excludes keys
fix[workflow]: simplify Matrix decode (because I "think" I know how yaml works) (fixes #760)
fix[tests]: add test for planner and runner

[codecov]

Codecov Report

Merging #763 (e3eb7df) into master (0f04942) will increase coverage by 4.22%.
The diff coverage is 63.08%.

@@            Coverage Diff             @@
##           master     #763      +/-   ##
==========================================
+ Coverage   49.27%   53.49%   +4.22%     
==========================================
  Files          23       23              
  Lines        2401     2658     +257     
==========================================
+ Hits         1183     1422     +239     
+ Misses       1090     1087       -3     
- Partials      128      149      +21     

Impacted Files	Coverage Δ
pkg/container/docker_build.go	0.00% <0.00%> (ø)
pkg/container/docker_run.go	1.83% <0.00%> (-0.10%)	⬇️
pkg/common/git.go	52.85% <30.15%> (-6.94%)	⬇️
pkg/runner/runner.go	68.96% <33.33%> (-7.51%)	⬇️
pkg/model/planner.go	51.85% <41.37%> (+18.76%)	⬆️
pkg/model/workflow.go	51.08% <62.68%> (+25.37%)	⬆️
pkg/container/docker_pull.go	36.17% <64.70%> (+17.98%)	⬆️
pkg/runner/expression.go	85.38% <71.87%> (-1.26%)	⬇️
pkg/runner/step_context.go	75.00% <76.34%> (+6.05%)	⬆️
pkg/runner/run_context.go	80.36% <98.55%> (+3.95%)	⬆️
... and 7 more

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[acjh]

fix[workflow]: ... hard fail on non-existing excludes

// ... because that's what GitHub does for non-existing matrix keys, fail on exclude, ...

GitHub doesn't appear to do that.
e.g. speedy-net/speedy-net/actions/runs/1025416111/workflow (Test only Python 3.6 and 3.7 on non-master/staging)

strategy:
  matrix:
    python-version: [3.6, 3.7, 3.8, 3.9]
    is-master-or-staging:
      - ${{ github.ref == 'refs/heads/master' || github.ref == 'refs/heads/staging' }}
    exclude:
      - python-version: 3.8
        is-master-or-staging: false
      - python-version: 3.9
        is-master-or-staging: false

[acjh]

Could you share a link to that workflow and/or your strategy section?

[catthehacker]

fix[workflow]: ... hard fail on non-existing excludes

// ... because that's what GitHub does for non-existing matrix keys, fail on exclude, ...

GitHub doesn't appear to do that.
e.g. speedy-net/speedy-net/actions/runs/1025416111/workflow (Test only Python 3.6 and 3.7 on non-master/staging)

strategy:
  matrix:
    python-version: [3.6, 3.7, 3.8, 3.9]
    is-master-or-staging:
      - ${{ github.ref == 'refs/heads/master' || github.ref == 'refs/heads/staging' }}
    exclude:
      - python-version: 3.8
        is-master-or-staging: false
      - python-version: 3.9
        is-master-or-staging: false

Your example has defined all required keys in matrix so that's why it's not failing

[acjh]

Ah, I misunderstood "non-existing excludes" as "excludes not existing in the cross product".
Instead, you mean "excludes with any key not existing in the matrix".

Thanks for the clarification and your good work!

[catthehacker]

updated commit description to mention that it's for keys