module Spec

Overview

Crystal's builtin testing library.

A basic spec looks like this:

require "spec"

describe "Array" do
  describe "#size" do
    it "correctly reports the number of elements in the Array" do
      [1, 2, 3].size.should eq 3
    end
  end

  describe "#empty?" do
    it "is empty when no elements are in the array" do
      ([] of Int32).empty?.should be_true
    end

    it "is not empty if there are elements in the array" do
      [1].empty?.should be_false
    end
  end

  # lots of more specs

end

With describe and a descriptive string test files are structured. There commonly is one top level describe that defines which greater unit, such as a class, is tested in this spec file. Further describe calls can be nested within to specify smaller units under test like individual methods. It can also be used to set up a certain context - think empty Array versus Array with elements. There is also the context method that behaves just like describe but has a lightly different meaning to the reader.

Concrete test cases are defined with it within a describe block. A descriptive string is supplied to it describing what that test case tests specifically.

Specs then use the should method to verify that the expected value is returned, see the example above for details.

By convention, specs live in the spec directory of a project. You can compile and run the specs of a project by running:

crystal spec

Also, you can compile and run individual spec files by providing their path:

crystal spec spec/my/test/file_spec.cr

In addition, you can also run individual specs by optionally providing a line number:

crystal spec spec/my/test/file_spec.cr:14

Defined in:

spec/context.cr
spec/expectations.cr
spec/formatter.cr
spec/source.cr
spec/spec.cr

Class Method Summary

Class Method Detail

def self.after_each(&block) #

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def self.before_each(&block) #

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def self.run #

:nodoc


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def self.use_colors=(use_colors) #

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def self.use_colors? #

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