Knowledge/Domain
Establishing that something works, and recognizing when you have established nothing.
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A defect whose occurrence depends on the relative timing of concurrent operations.
Testing & Verification·22 connections
A fast, isolated test of one unit of behavior with its collaborators replaced.
Testing & Verification·18 connections
A test that passes and fails on identical input, and the most corrosive thing a suite can contain.
Testing & Verification·17 connections
Adding measurement to code so its execution can be observed, and the distortions that introduces.
An isolated rendered instance of a component, usable as documentation, a workbench, and a test.
Testing & Verification·16 connections
A build check that fails when coverage falls below a threshold, and what that pressure produces.
The statement in a test that must hold, and the only part that can actually fail.
Testing & Verification·14 connections
The proportion of code executed by a test suite — a map of what is untested, not a measure of quality.
The prepared data or state a test runs against.
Testing & Verification·13 connections
The proportion of conditional outcomes exercised — the strictest ordinary coverage metric, and the most informative.
Testing & Verification·12 connections
A test exercising several components together, through real interfaces rather than doubles.
Failures caused by competition for a finite shared resource rather than by any defect.
A stand-in for a real dependency during a test — and the ways a stand-in can lie.
Comparing rendered output against a stored baseline to catch unintended visual change.
A real browser driven programmatically without a visible window.
Testing & Verification·10 connections
Writing a failing test first, making it pass, then improving the code with the test as a net.
Code no input can execute — usually a guard against a state the surrounding invariants forbid.
A fault that changes or disappears when someone tries to observe it.
Testing & Verification·8 connections
A fast, shallow check that a build isn't catastrophically broken, run before investing in a deeper test pass.
Testing & Verification·7 connections
Verifying that a service and its consumer agree on an interface's shape, without either side needing the other running to test against.
Testing & Verification·6 connections
A test-of-tests that injects small bugs into code and checks whether the existing suite catches them, exposing tests that assert nothing.
Comparing a component or output's current rendering against a saved baseline, flagging any difference for a human to accept or reject.
Testing & Verification·5 connections
Comparing an output against a checked-in reference file the whole team agreed was correct, rather than an inline assertion.
Testing & Verification·4 connections
Asserting a general property that should hold for all inputs, then letting the framework generate many random inputs to try to break it.