class Mocha::Configuration
This class provides a number of ways to configure the library.
Typically the configuration is set globally in a test_helper.rb
or spec_helper.rb
file.
@example Setting multiple configuration options
Mocha.configure do |c| c.stubbing_method_unnecessarily = :prevent c.stubbing_method_on_non_mock_object = :warn c.stubbing_method_on_nil = :allow end
Constants
- DEFAULTS
@private
Attributes
Public Class Methods
@private
# File lib/mocha/configuration.rb, line 327 def configuration @configuration ||= new end
@private
# File lib/mocha/configuration.rb, line 55 def initialize(options = {}) @options = DEFAULTS.merge(options) end
Temporarily modify {Configuration} options.
The supplied temporary_options
will override the current configuration for the duration of the supplied block. The configuration will be returned to its original state when the block returns.
@param [Hash] temporary_options the configuration options to apply for the duration of the block. @yield block during which the configuration change will be in force.
@example Temporarily allow stubbing of nil
Mocha::Configuration.override(stubbing_method_on_nil: :allow) do nil.stubs(:foo) end
# File lib/mocha/configuration.rb, line 318 def override(temporary_options) original_configuration = configuration @configuration = configuration.merge(new(temporary_options)) yield ensure @configuration = original_configuration end
@private
# File lib/mocha/configuration.rb, line 302 def reset_configuration @configuration = nil end
Private Class Methods
@private
# File lib/mocha/configuration.rb, line 334 def change_config(action, new_value, &block) if block_given? temporarily_change_config action, new_value, &block else configuration.send("#{action}=".to_sym, new_value) end end
@private
# File lib/mocha/configuration.rb, line 343 def temporarily_change_config(action, new_value) original_configuration = configuration new_configuration = configuration.dup new_configuration.send("#{action}=".to_sym, new_value) @configuration = new_configuration yield ensure @configuration = original_configuration end
Public Instance Methods
Display matching invocations alongside expectations on Mocha-related test failure.
@param [Boolean] value true
to enable display of matching invocations; disabled by default.
@example Enable display of matching invocations
Mocha.configure do |c| c.display_matching_invocations_on_failure = true end foo = mock('foo') foo.expects(:bar) foo.stubs(:baz).returns('baz').raises(RuntimeError).throws(:tag, 'value') foo.baz(1, 2) assert_raises(RuntimeError) { foo.baz(3, 4) } assert_throws(:tag) { foo.baz(5, 6) } not all expectations were satisfied unsatisfied expectations: - expected exactly once, invoked never: #<Mock:foo>.bar satisfied expectations: - allowed any number of times, invoked 3 times: #<Mock:foo>.baz(any_parameters) - #<Mock:foo>.baz(1, 2) # => "baz" - #<Mock:foo>.baz(3, 4) # => raised RuntimeError - #<Mock:foo>.baz(5, 6) # => threw (:tag, "value")
# File lib/mocha/configuration.rb, line 244 def display_matching_invocations_on_failure=(value) @options[:display_matching_invocations_on_failure] = value end
@private
# File lib/mocha/configuration.rb, line 249 def display_matching_invocations_on_failure? @options[:display_matching_invocations_on_failure] end
@private
# File lib/mocha/configuration.rb, line 60 def initialize_copy(other) @options = other.options.dup end
@private
# File lib/mocha/configuration.rb, line 65 def merge(other) self.class.new(@options.merge(other.options)) end
Perform strict keyword argument comparison. Only supported in Ruby >= v2.7.
When this option is set to false
a positional Hash
and a set of keyword arguments are treated the same during comparison, which can lead to misleading passing tests in Ruby >= v3.0 (see examples below). However, a deprecation warning will be displayed if a positional Hash
matches a set of keyword arguments or vice versa. This is because {#strict_keyword_argument_matching=} will default to true
in the future.
For more details on keyword arguments in Ruby v3, refer to {www.ruby-lang.org/en/news/2019/12/12/separation-of-positional-and-keyword-arguments-in-ruby-3-0 this article}.
Note that Hash
-related matchers such as {ParameterMatchers#has_value} or {ParameterMatchers#has_key} will still treat a positional Hash
and a set of keyword arguments the same, so misleading passing tests are still possible when they are used.
This configuration option is false
by default to enable gradual adoption, but will be true
by default in the future.
@param [Boolean] value true
to enable strict keyword argument matching; false
by default.
@example Loose keyword argument matching (default)
class Example def foo(a, bar:); end end example = Example.new example.expects(:foo).with('a', bar: 'b') example.foo('a', { bar: 'b' }) # This passes the test, but would result in an ArgumentError in practice
@example Strict keyword argument matching
Mocha.configure do |c| c.strict_keyword_argument_matching = true end class Example def foo(a, bar:); end end example = Example.new example.expects(:foo).with('a', bar: 'b') example.foo('a', { bar: 'b' }) # This now fails as expected
# File lib/mocha/configuration.rb, line 290 def strict_keyword_argument_matching=(value) raise 'Strict keyword argument matching requires Ruby 2.7 and above.' unless Mocha::RUBY_V27_PLUS @options[:strict_keyword_argument_matching] = value end
@private
# File lib/mocha/configuration.rb, line 296 def strict_keyword_argument_matching? @options[:strict_keyword_argument_matching] end
@private
# File lib/mocha/configuration.rb, line 215 def stubbing_method_on_nil @options[:stubbing_method_on_nil] end
Configure whether stubbing methods on the nil
object is allowed.
This is usually done accidentally, but there might be rare cases where it is intended.
This option only works for Ruby < v2.2.0. In later versions of Ruby nil
is frozen and so a {StubbingError} will be raised if you attempt to stub a method on nil
.
When value
is :allow
, do nothing. When value
is :warn
, display a warning. When value
is :prevent
, raise a {StubbingError}. This is the default.
@param [Symbol] value one of :allow
, :warn
, :prevent
.
# File lib/mocha/configuration.rb, line 210 def stubbing_method_on_nil=(value) @options[:stubbing_method_on_nil] = value end
@private
# File lib/mocha/configuration.rb, line 127 def stubbing_method_on_non_mock_object @options[:stubbing_method_on_non_mock_object] end
Configure whether stubbing methods on non-mock objects is allowed.
If you like the idea of {www.jmock.org/oopsla2004.pdf mocking roles not objects} and {www.mockobjects.com/2007/04/test-smell-mocking-concrete-classes.html you don’t like stubbing concrete classes}, this is the setting for you. However, while this restriction makes a lot of sense in Java with its {java.sun.com/docs/books/tutorial/java/concepts/interface.html explicit interfaces}, it may be moot in Ruby where roles are probably best represented as Modules.
When value
is :allow
, do nothing. This is the default. When value
is :warn
, display a warning. When value
is :prevent
, raise a {StubbingError}.
@param [Symbol] value one of :allow
, :warn
, :prevent
.
@example Preventing stubbing of a method on a non-mock object
Mocha.configure do |c| c.stubbing_method_on_non_mock_object = :prevent end class Example def example_method; end end example = Example.new example.stubs(:example_method) # => Mocha::StubbingError: stubbing method on non-mock object: # => #<Example:0x593620>.example_method
# File lib/mocha/configuration.rb, line 122 def stubbing_method_on_non_mock_object=(value) @options[:stubbing_method_on_non_mock_object] = value end
@private
# File lib/mocha/configuration.rb, line 94 def stubbing_method_unnecessarily @options[:stubbing_method_unnecessarily] end
Configure whether stubbing methods unnecessarily is allowed.
This is useful for identifying unused stubs. Unused stubs are often accidentally introduced when code is {martinfowler.com/bliki/DefinitionOfRefactoring.html refactored}.
When value
is :allow
, do nothing. This is the default. When value
is :warn
, display a warning. When value
is :prevent
, raise a {StubbingError}.
@param [Symbol] value one of :allow
, :warn
, :prevent
.
@example Preventing unnecessary stubbing of a method
Mocha.configure do |c| c.stubbing_method_unnecessarily = :prevent end example = mock('example') example.stubs(:unused_stub) # => Mocha::StubbingError: stubbing method unnecessarily: # => #<Mock:example>.unused_stub(any_parameters)
# File lib/mocha/configuration.rb, line 89 def stubbing_method_unnecessarily=(value) @options[:stubbing_method_unnecessarily] = value end
@private
# File lib/mocha/configuration.rb, line 160 def stubbing_non_existent_method @options[:stubbing_non_existent_method] end
Configure whether stubbing of non-existent methods is allowed.
This is useful if you want to ensure that methods you’re mocking really exist. A common criticism of unit tests with mock objects is that such a test may (incorrectly) pass when an equivalent non-mocking test would (correctly) fail. While you should always have some integration tests, particularly for critical business functionality, this Mocha
configuration setting should catch scenarios when mocked methods and real methods have become misaligned.
When value
is :allow
, do nothing. This is the default. When value
is :warn
, display a warning. When value
is :prevent
, raise a {StubbingError}.
@param [Symbol] value one of :allow
, :warn
, :prevent
.
@example Preventing stubbing of a non-existent method
Mocha.configure do |c| c.stubbing_non_existent_method = :prevent end class Example end example = Example.new example.stubs(:method_that_doesnt_exist) # => Mocha::StubbingError: stubbing non-existent method: # => #<Example:0x593760>.method_that_doesnt_exist
# File lib/mocha/configuration.rb, line 155 def stubbing_non_existent_method=(value) @options[:stubbing_non_existent_method] = value end
@private
# File lib/mocha/configuration.rb, line 194 def stubbing_non_public_method @options[:stubbing_non_public_method] end
Configure whether stubbing of non-public methods is allowed.
Many people think that it’s good practice only to mock public methods. This is one way to prevent your tests being too tightly coupled to the internal implementation of a class. Such tests tend to be very brittle and not much use when refactoring.
When value
is :allow
, do nothing. This is the default. When value
is :warn
, display a warning. When value
is :prevent
, raise a {StubbingError}.
@param [Symbol] value one of :allow
, :warn
, :prevent
.
@example Preventing stubbing of a non-public method
Mocha.configure do |c| c.stubbing_non_public_method = :prevent end class Example def internal_method; end private :internal_method end example = Example.new example.stubs(:internal_method) # => Mocha::StubbingError: stubbing non-public method: # => #<Example:0x593530>.internal_method
# File lib/mocha/configuration.rb, line 189 def stubbing_non_public_method=(value) @options[:stubbing_non_public_method] = value end