Class: RSpec::Expectations::WhenExpectationTarget

Inherits:
ExpectationTarget
  • Object
show all
Defined in:
lib/rspec/expectations/when_expectation_target.rb

Overview

Note:

‘WhenExpectationTarget` is not intended to be instantiated directly. Use `expect(target).when(flag)` instead

Wraps the target of an expectation and allowing of optional expectations as well as testing expectation inverses

Examples:

expect(something).when(flag) # => WhenExpectationTarget testing when `flag`

# `when` used with `to`
expect(actual).when(flag).to eq(3)
# is the equivalent of
if flag
  expect(actual).to eq(3)
end

# `when` used with `with_inverse` and `to`
expect(actual).when(flag).with_inverse.to eq(3)
# is the equivalent of
if flag
  expect(actual).to eq(3)
else
  expect(actual).not_to eq(3)
end

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(value, when_expected) ⇒ WhenExpectationTarget

Returns a new instance of WhenExpectationTarget.



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 35

def initialize(value, when_expected)
  @target = value
  @when_expected = when_expected
  @with_inverse = false
end

Instance Attribute Details

#target ⇒ Object (readonly)

Returns the target of the expectation.

Returns:

  • (Object) —

    the target of the expectation



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 30

def target
  @target
end

#when_expected ⇒ Boolean (readonly)

Returns is the target expected?.

Returns:

  • (Boolean) —

    is the target expected?



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 33

def when_expected
  @when_expected
end

Instance Method Details

#expect_not_to ⇒ Object 



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 49

alias_method :expect_not_to, :not_to

#expect_to ⇒ Object 



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 48

alias_method :expect_to, :to

#not_to(matcher = nil, message = nil, &block) ⇒ Boolean Also known as: to_not

When expected, it will run the given expectation, passing if ‘matcher` returns false. When not expected and we’re also testing the inverse, it will run the given expectation, passing if ‘matcher` returns true.

Examples:

expect(value).when(flag).not_to eq(5)
expect(value).when(flag).with_inverse.not_to eq(5)

Parameters:

  • matcher (Matcher) (defaults to: nil)
  • message (String or Proc) (defaults to: nil) —

    optional message to display when the expectation fails

Returns:

  • (Boolean) —

    false if the negative expectation succeeds (else raises)

See Also:

  • Matchers


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# File 'lib/rspec/expectations/when_expectation_target.rb', line 82

def not_to(matcher = nil, message = nil, &block)
  if @when_expected
    super
  elsif @with_inverse
    expect_to matcher, message, &block
  end
end

#to(matcher = nil, message = nil, &block) ⇒ Boolean

When expected, it will run the given expectation, passing if ‘matcher` returns true. When not expected and we’re also testing the inverse, it will run the given expectation, passing if ‘matcher` returns false.

Examples:

expect(value).when(flag).to eq(5)
expect(value).when(flag).with_inverse.to eq(5)
expect { perform }.when(flag).to raise_error

Parameters:

  • matcher (Matcher) (defaults to: nil)
  • message (String or Proc) (defaults to: nil) —

    optional message to display when the expectation fails

Returns:

  • (Boolean) —

    true if the expectation succeeds (else raises)

See Also:

  • Matchers


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# File 'lib/rspec/expectations/when_expectation_target.rb', line 63

def to(matcher = nil, message = nil, &block)
  if @when_expected
    super
  elsif @with_inverse
    expect_not_to matcher, message, &block
  end
end

#with_inverse ⇒ Object

Indicates whether the inverse of the expectation should be applied should the ‘when` flag be false



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# File 'lib/rspec/expectations/when_expectation_target.rb', line 43

def with_inverse
  @with_inverse = true
  self
end