Agent WranglersCharacterization tests
Before changing inherited code, record what it does today in tests. Keep known bugs pinned until their own fix, and cut seams to reach hard code.
- Recommended 3
Recommended
Pin today's behaviour before changing code
TKO-8Before you change a module, write tests that record what it does today for the inputs it gets in production. They must pass on the code as it is now.
Keep known bugs pinned until their own fix
TKO-9When a characterization test records a bug, keep the buggy output as expected and link the test to a ticket. Fix the bug in a separate change that updates that one test.
Cut a seam before testing hard code
TKO-10When code reads the clock, the network, the database or a global directly, make the smallest change that lets a test pass that dependency in. Make no other change in the same step.
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