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Project: RSpec Expectations 3.4

Publisher: RSpec

`contain_exactly` matcher

The contain_exactly matcher provides a way to test arrays against each other in a way
that disregards differences in the ordering between the actual and expected array.
For example:

  expect([1, 2, 3]).to    contain_exactly(2, 3, 1) # pass
  expect([:a, :c, :b]).to contain_exactly(:a, :c ) # fail

This matcher is also available as match_array, which expects the expected array to be
given as a single array argument rather than as individual splatted elements. The above
could also be written as:

  expect([1, 2, 3]).to    match_array [2, 3, 1] # pass
  expect([:a, :c, :b]).to match_array [:a, :c]  # fail
Scenarios
Array is expected to contain every value
Given
a file named "contain_exactly_matcher_spec.rb" with: 
RSpec.describe [1, 2, 3] do
  it { is_expected.to contain_exactly(1, 2, 3) }
  it { is_expected.to contain_exactly(1, 3, 2) }
  it { is_expected.to contain_exactly(2, 1, 3) }
  it { is_expected.to contain_exactly(2, 3, 1) }
  it { is_expected.to contain_exactly(3, 1, 2) }
  it { is_expected.to contain_exactly(3, 2, 1) }

  # deliberate failures
  it { is_expected.to contain_exactly(1, 2, 1) }
end
When
I run rspec contain_exactly_matcher_spec.rb
Then
the output should contain "7 examples, 1 failure"
And
the output should contain: 
     Failure/Error: it { is_expected.to contain_exactly(1, 2, 1) }
       expected collection contained:  [1, 1, 2]
       actual collection contained:    [1, 2, 3]
       the missing elements were:      [1]
       the extra elements were:        [3]
Array is not expected to contain every value
Given
a file named "contain_exactly_matcher_spec.rb" with: 
RSpec.describe [1, 2, 3] do
  it { is_expected.to_not contain_exactly(1, 2, 3, 4) }
  it { is_expected.to_not contain_exactly(1, 2) }

  # deliberate failures
  it { is_expected.to_not contain_exactly(1, 3, 2) }
end
When
I run rspec contain_exactly_matcher_spec.rb
Then
the output should contain "3 examples, 1 failure"
And
the output should contain: 
     Failure/Error: it { is_expected.to_not contain_exactly(1, 3, 2) }
       expected [1, 2, 3] not to contain exactly 1, 3, and 2

Last published over 5 years ago by myronmarston.