class RSpec::Core::ExampleGroup
rubocop:disable Metrics/ClassLength ExampleGroup and {Example} are the main structural elements of rspec-core. Consider this example:
describe Thing do it "does something" do end end
The object returned by `describe Thing` is a subclass of ExampleGroup. The object returned by `it “does something”` is an instance of Example, which serves as a wrapper for an instance of the ExampleGroup in which it is declared.
Example group bodies (e.g. `describe` or `context` blocks) are evaluated in the context of a new subclass of ExampleGroup. Individual examples are evaluated in the context of an instance of the specific ExampleGroup subclass to which they belong.
Besides the class methods defined here, there are other interesting macros defined in {Hooks}, {MemoizedHelpers::ClassMethods} and {SharedExampleGroup}. There are additional instance methods available to your examples defined in {MemoizedHelpers} and {Pending}.
Constants
- INSTANCE_VARIABLE_TO_IGNORE
:nocov: @private
- WrongScopeError
Raised when an RSpec API is called in the wrong scope, such as `before` being called from within an example rather than from within an example group block.
Public Class Methods
Adds an example to the example group
# File lib/rspec/core/example_group.rb, line 354 def self.add_example(example) reset_memoized examples << example end
@private
# File lib/rspec/core/example_group.rb, line 478 def self.before_context_ivars @before_context_ivars ||= {} end
@private
# File lib/rspec/core/example_group.rb, line 438 def self.children @children ||= [] end
@private
# File lib/rspec/core/example_group.rb, line 602 def self.declaration_line_numbers @declaration_line_numbers ||= [metadata[:line_number]] + examples.map { |e| e.metadata[:line_number] } + FlatMap.flat_map(children, &:declaration_line_numbers) end
@private @macro [attach] ::define_example_group_method
@!scope class @overload $1 @overload $1(&example_group_definition) @param example_group_definition [Block] The definition of the example group. @overload $1(doc_string, *metadata_keys, metadata={}, &example_implementation) @param doc_string [String] The group's doc string. @param metadata [Hash] Metadata for the group. @param metadata_keys [Array<Symbol>] Metadata tags for the group. Will be transformed into hash entries with `true` values. @param example_group_definition [Block] The definition of the example group. Generates a subclass of this example group which inherits everything except the examples themselves. @example RSpec.describe "something" do # << This describe method is defined in # << RSpec::Core::DSL, included in the # << global namespace (optional) before do do_something_before end let(:thing) { Thing.new } $1 "attribute (of something)" do # examples in the group get the before hook # declared above, and can access `thing` end end
@see DSL#describe
# File lib/rspec/core/example_group.rb, line 233 def self.define_example_group_method(name, metadata={}) idempotently_define_singleton_method(name) do |*args, &example_group_block| thread_data = RSpec::Support.thread_local_data top_level = self == ExampleGroup if top_level if thread_data[:in_example_group] raise "Creating an isolated context from within a context is " "not allowed. Change `RSpec.#{name}` to `#{name}` or " "move this to a top-level scope." end thread_data[:in_example_group] = true end begin description = args.shift combined_metadata = metadata.dup combined_metadata.merge!(args.pop) if args.last.is_a? Hash args << combined_metadata subclass(self, description, args, &example_group_block).tap do |child| children << child end ensure thread_data.delete(:in_example_group) if top_level end end RSpec::Core::DSL.expose_example_group_alias(name) end
@private @macro [attach] ::define_example_method
@!scope class @overload $1 @overload $1(&example_implementation) @param example_implementation [Block] The implementation of the example. @overload $1(doc_string, *metadata_keys, metadata={}) @param doc_string [String] The example's doc string. @param metadata [Hash] Metadata for the example. @param metadata_keys [Array<Symbol>] Metadata tags for the example. Will be transformed into hash entries with `true` values. @overload $1(doc_string, *metadata_keys, metadata={}, &example_implementation) @param doc_string [String] The example's doc string. @param metadata [Hash] Metadata for the example. @param metadata_keys [Array<Symbol>] Metadata tags for the example. Will be transformed into hash entries with `true` values. @param example_implementation [Block] The implementation of the example. @yield [Example] the example object @example $1 do end $1 "does something" do end $1 "does something", :slow, :uses_js do end $1 "does something", :with => 'additional metadata' do end $1 "does something" do |ex| # ex is the Example object that contains metadata about the example end
# File lib/rspec/core/example_group.rb, line 138 def self.define_example_method(name, extra_options={}) idempotently_define_singleton_method(name) do |*all_args, &block| desc, *args = *all_args options = Metadata.build_hash_from(args) options.update(:skip => RSpec::Core::Pending::NOT_YET_IMPLEMENTED) unless block options.update(extra_options) example = RSpec::Core::Example.new(self, desc, options, block) examples << example example end end
@private
# File lib/rspec/core/example_group.rb, line 73 def self.delegate_to_metadata(*names) names.each do |name| idempotently_define_singleton_method(name) { metadata.fetch(name) } end end
@private
# File lib/rspec/core/example_group.rb, line 432 def self.descendant_filtered_examples @descendant_filtered_examples ||= filtered_examples + FlatMap.flat_map(children, &:descendant_filtered_examples) end
@private
# File lib/rspec/core/example_group.rb, line 452 def self.descendants @_descendants ||= [self] + FlatMap.flat_map(children, &:descendants) end
@return [String] the current example group description
# File lib/rspec/core/example_group.rb, line 82 def self.description description = metadata[:description] RSpec.configuration.format_docstrings_block.call(description) end
@private
# File lib/rspec/core/example_group.rb, line 635 def self.each_instance_variable_for_example(group) group.instance_variables.each do |ivar| yield ivar unless ivar == INSTANCE_VARIABLE_TO_IGNORE end end
@private
# File lib/rspec/core/example_group.rb, line 467 def self.ensure_example_groups_are_configured unless defined?(@@example_groups_configured) RSpec.configuration.configure_mock_framework RSpec.configuration.configure_expectation_framework # rubocop:disable Style/ClassVars @@example_groups_configured = true # rubocop:enable Style/ClassVars end end
@private
# File lib/rspec/core/example_group.rb, line 422 def self.examples @examples ||= [] end
@private
# File lib/rspec/core/example_group.rb, line 427 def self.filtered_examples RSpec.world.filtered_examples[self] end
@private
# File lib/rspec/core/example_group.rb, line 590 def self.for_filtered_examples(reporter, &block) filtered_examples.each(&block) children.each do |child| reporter.example_group_started(child) child.for_filtered_examples(reporter, &block) reporter.example_group_finished(child) end false end
@return [String] the unique id of this example group. Pass
this at the command line to re-run this exact example group.
# File lib/rspec/core/example_group.rb, line 610 def self.id Metadata.id_from(metadata) end
@private
# File lib/rspec/core/example_group.rb, line 37 def self.idempotently_define_singleton_method(name, &definition) (class << self; self; end).module_exec do remove_method(name) if method_defined?(name) && instance_method(name).owner == self define_method(name, &definition) end end
Includes shared content mapped to `name` directly in the group in which it is declared, as opposed to `it_behaves_like`, which creates a nested group. If given a block, that block is also eval'd in the current context.
@see SharedExampleGroup
# File lib/rspec/core/example_group.rb, line 330 def self.include_context(name, *args, &block) find_and_eval_shared("context", name, caller.first, *args, &block) end
Includes shared content mapped to `name` directly in the group in which it is declared, as opposed to `it_behaves_like`, which creates a nested group. If given a block, that block is also eval'd in the current context.
@see SharedExampleGroup
# File lib/rspec/core/example_group.rb, line 340 def self.include_examples(name, *args, &block) find_and_eval_shared("examples", name, caller.first, *args, &block) end
The [Metadata](Metadata) object associated with this group. @see Metadata
# File lib/rspec/core/example_group.rb, line 48 def self.metadata @metadata ||= nil end
# File lib/rspec/core/example_group.rb, line 641 def initialize(inspect_output=nil) @__inspect_output = inspect_output || '(no description provided)' super() # no args get passed end
@private
# File lib/rspec/core/example_group.rb, line 443 def self.next_runnable_index_for(file) if self == ExampleGroup RSpec.world.num_example_groups_defined_in(file) else children.count + examples.count end + 1 end
@private
# File lib/rspec/core/example_group.rb, line 560 def self.ordering_strategy order = metadata.fetch(:order, :global) registry = RSpec.configuration.ordering_registry registry.fetch(order) do warn " |WARNING: Ignoring unknown ordering specified using `:order => #{order.inspect}` metadata. | Falling back to configured global ordering. | Unrecognized ordering specified at: #{location} ".gsub(/^ +\|/, '') registry.fetch(:global) end end
@private
# File lib/rspec/core/example_group.rb, line 457 def self.parent_groups @parent_groups ||= ancestors.select { |a| a < RSpec::Core::ExampleGroup } end
Removes an example from the example group
# File lib/rspec/core/example_group.rb, line 360 def self.remove_example(example) reset_memoized examples.delete example end
Clear memoized values when adding/removing examples @private
# File lib/rspec/core/example_group.rb, line 346 def self.reset_memoized @descendant_filtered_examples = nil @_descendants = nil @parent_groups = nil @declaration_line_numbers = nil end
Runs all the examples in this group.
# File lib/rspec/core/example_group.rb, line 536 def self.run(reporter=RSpec::Core::NullReporter) return if RSpec.world.wants_to_quit reporter.example_group_started(self) should_run_context_hooks = descendant_filtered_examples.any? begin run_before_context_hooks(new('before(:context) hook')) if should_run_context_hooks result_for_this_group = run_examples(reporter) results_for_descendants = ordering_strategy.order(children).map { |child| child.run(reporter) }.all? result_for_this_group && results_for_descendants rescue Pending::SkipDeclaredInExample => ex for_filtered_examples(reporter) { |example| example.skip_with_exception(reporter, ex) } true rescue Support::AllExceptionsExceptOnesWeMustNotRescue => ex for_filtered_examples(reporter) { |example| example.fail_with_exception(reporter, ex) } RSpec.world.wants_to_quit = true if reporter.fail_fast_limit_met? false ensure run_after_context_hooks(new('after(:context) hook')) if should_run_context_hooks reporter.example_group_finished(self) end end
@private
# File lib/rspec/core/example_group.rb, line 525 def self.run_after_context_hooks(example_group_instance) set_ivars(example_group_instance, before_context_ivars) ContextHookMemoized::After.isolate_for_context_hook(example_group_instance) do hooks.run(:after, :context, example_group_instance) end ensure before_context_ivars.clear end
@private
# File lib/rspec/core/example_group.rb, line 490 def self.run_before_context_hooks(example_group_instance) set_ivars(example_group_instance, superclass_before_context_ivars) ContextHookMemoized::Before.isolate_for_context_hook(example_group_instance) do hooks.run(:before, :context, example_group_instance) end ensure store_before_context_ivars(example_group_instance) end
@private
# File lib/rspec/core/example_group.rb, line 576 def self.run_examples(reporter) ordering_strategy.order(filtered_examples).map do |example| next if RSpec.world.wants_to_quit instance = new(example.inspect_output) set_ivars(instance, before_context_ivars) succeeded = example.run(instance, reporter) if !succeeded && reporter.fail_fast_limit_met? RSpec.world.wants_to_quit = true end succeeded end.all? end
@private
# File lib/rspec/core/example_group.rb, line 397 def self.set_it_up(description, *args, &example_group_block) # Ruby 1.9 has a bug that can lead to infinite recursion and a # SystemStackError if you include a module in a superclass after # including it in a subclass: https://gist.github.com/845896 # To prevent this, we must include any modules in # RSpec::Core::ExampleGroup before users create example groups and have # a chance to include the same module in a subclass of # RSpec::Core::ExampleGroup. So we need to configure example groups # here. ensure_example_groups_are_configured user_metadata = Metadata.build_hash_from(args) @metadata = Metadata::ExampleGroupHash.create( superclass_metadata, user_metadata, superclass.method(:next_runnable_index_for), description, *args, &example_group_block ) ExampleGroups.assign_const(self) hooks.register_globals(self, RSpec.configuration.hooks) RSpec.configuration.configure_group(self) end
@private
# File lib/rspec/core/example_group.rb, line 620 def self.set_ivars(instance, ivars) ivars.each { |name, value| instance.instance_variable_set(name, value) } end
@private
# File lib/rspec/core/example_group.rb, line 483 def self.store_before_context_ivars(example_group_instance) each_instance_variable_for_example(example_group_instance) do |ivar| before_context_ivars[ivar] = example_group_instance.instance_variable_get(ivar) end end
@private
# File lib/rspec/core/example_group.rb, line 382 def self.subclass(parent, description, args, &example_group_block) subclass = Class.new(parent) subclass.set_it_up(description, *args, &example_group_block) subclass.module_exec(&example_group_block) if example_group_block # The LetDefinitions module must be included _after_ other modules # to ensure that it takes precedence when there are name collisions. # Thus, we delay including it until after the example group block # has been eval'd. MemoizedHelpers.define_helpers_on(subclass) subclass end
@private
# File lib/rspec/core/example_group.rb, line 502 def self.superclass_before_context_ivars superclass.before_context_ivars end
@private @return [Metadata] belonging to the parent of a nested {ExampleGroup}
# File lib/rspec/core/example_group.rb, line 68 def self.superclass_metadata @superclass_metadata ||= superclass.respond_to?(:metadata) ? superclass.metadata : nil end
@private
# File lib/rspec/core/example_group.rb, line 462 def self.top_level? superclass == ExampleGroup end
@private
# File lib/rspec/core/example_group.rb, line 615 def self.top_level_description parent_groups.last.description end
Temporarily replace the provided metadata. Intended primarily to allow an example group's singleton class to return the metadata of the example that it exists for. This is necessary for shared example group inclusion to work properly with singleton example groups. @private
# File lib/rspec/core/example_group.rb, line 58 def self.with_replaced_metadata(meta) orig_metadata = metadata @metadata = meta yield ensure @metadata = orig_metadata end
Private Class Methods
# File lib/rspec/core/example_group.rb, line 665 def self.method_missing(name, *args) if method_defined?(name) raise WrongScopeError, "`#{name}` is not available on an example group (e.g. a " "`describe` or `context` block). It is only available from " "within individual examples (e.g. `it` blocks) or from " "constructs that run in the scope of an example (e.g. " "`before`, `let`, etc)." end super end
Public Instance Methods
Returns the class or module passed to the `describe` method (or alias). Returns nil if the subject is not a class or module. @example
describe Thing do it "does something" do described_class == Thing end end
# File lib/rspec/core/example_group.rb, line 96 def described_class self.class.described_class end
@private
# File lib/rspec/core/example_group.rb, line 647 def inspect "#<#{self.class} #{@__inspect_output}>" end
:nocov: @private
# File lib/rspec/core/example_group.rb, line 654 def singleton_class class << self; self; end end
Private Instance Methods
# File lib/rspec/core/example_group.rb, line 681 def method_missing(name, *args) if self.class.respond_to?(name) raise WrongScopeError, "`#{name}` is not available from within an example (e.g. an " "`it` block) or from constructs that run in the scope of an " "example (e.g. `before`, `let`, etc). It is only available " "on an example group (e.g. a `describe` or `context` block)." end super end