Improve unit test infrastructure and coverage

[John-Sharples]

Describe the Enhancement

Improve how the tests are invoked and run. Add a conftest.py file and use this for common fixtures and setup.

Time Estimate

~ 4 weeks

Sub-Issues

Consider breaking the enhancement down into sub-issues.

• create conftest
• get all tests running from simple pytest call
• improve tests coverage

Relevant Deadlines

By end of @John-Sharples visitor project

Funding Source

Visitor program

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Assignee

• @John-Sharples
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Milestone and Projects

• Select Milestone as a METplotpy-X.Y.Z version, Consider for Next Release, or Backlog of Development Ideas
• For a METplotpy-X.Y.Z version, select the METplotpy-X.Y.Z Development project

Define Related Issue(s)

Consider the impact to the other METplus components.

• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

Enhancement Checklist

See the METplus Workflow for details.

• Complete the issue definition above, including the Time Estimate and Funding Source.
• Fork this repository or create a branch of develop.
  Branch name: feature_<Issue Number>_<Description>
• Complete the development and test your changes.
• Add/update log messages for easier debugging.
• Add/update unit tests.
• Add/update documentation.
• Add any new Python packages to the METplus Components Python Requirements table.
• Push local changes to GitHub.
• Submit a pull request to merge into develop.
  Pull request: feature <Issue Number> <Description>
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  Select: Reviewer(s) and Development issue
  Select: Milestone as the next official version
  Select: METplotpy-X.Y.Z Development project for development toward the next official release
• Iterate until the reviewer(s) accept and merge your changes.
• Delete your fork or branch.
• Close this issue.