To add a collaborator to this project you will need to use the Relish gem to add the collaborator via a terminal command. Soon you'll be able to also add collaborators here!
More about adding a collaboratorDefine negated matcher
You can use RSpec::Matchers.define_negated_matcher
to define a negated version of
an existing matcher. This is particularly useful in composed matcher expressions.
- Scenarios
-
- Composed negated matcher expression
-
- Given
-
a file named "composed_negated_expression_spec.rb" with:
RSpec::Matchers.define_negated_matcher :an_array_excluding, :include RSpec.describe "A negated matcher" do let(:list) { 1.upto(10).to_a } it "can be used in a composed matcher expression" do expect { list.delete(5) }.to change { list }.to(an_array_excluding 5) end it "provides a good failure message based on the name" do # deliberate failure expect { list.delete(1) }.to change { list }.to(an_array_excluding 5) end end
- When
-
I run
rspec composed_negated_expression_spec.rb
- Then
-
the output should contain all of these:
2 examples, 1 failure 1) A negated matcher provides a good failure message based on the name Failure/Error: expect { list.delete(1) }.to change { list }.to(an_array_excluding 5) expected list
to have changed to an array excluding 5, but is now [2, 3, 4, 5, 6, 7, 8, 9, 10]
Last published about 2 years ago by Jon Rowe.