Refactor test `RUN` commands into a separate tool - #355

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mattmccutchen-cci wants to merge 5 commits into

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test-command-refactoring

Commits on Jan 13, 2021

Add 3c-regtest.py and migrate one example test to use it.
mattmccutchen-cci
committed
2ecd734
Redesign to support verification that a test file has been correctly
mattmccutchen-cci
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15d87eb
Remove the tests that were deleted in #364 from test_updater.py.
mattmccutchen-cci
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17f60c0
Convert the rest of the tests managed by the "test updating programs" to
mattmccutchen-cci
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b1745b6
A few test_updater tests no longer need a "diff -w".
mattmccutchen-cci
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6691373