jest: javascript testing framwork

"Jester's privilege is the ability and right of a jester to talk and mock freely without being punished."

In this post, I will be playing with some of the tools under a jest.js' belt that helps him deploy his privilege. 

A basic building block of the jest.js program is a test.

A test is a series or a singular combination of expectation followed by a matcher.

The simplest way to explicitly specify an expectation is using the expect method.



When Jest runs, it tracks all the failing matchers and prints out error messages based on that.

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