Software Engineering at Google: Lessons Learned from Programming Over Time

by Titus Winters

a test’s body should contain all of the information needed to understand it without containing any irrelevant or distracting information.

There’s a better way: rather than writing a test for each method, write a test for each behavior.4 A behavior is any guarantee that a system makes about how it will respond to a series of inputs while in a particular state.5

The pendulum at Google has now begun swinging in the other direction, with many engineers avoiding mocking frameworks in favor of writing more realistic tests.