module RSpec
module Core
# 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.
class ExampleGroup
extend Hooks
include MemoizedHelpers
include Pending
extend SharedExampleGroup
# @private
def self.world
RSpec.world
end
# @private
def self.register
world.register(self)
end
class << self
# @private
def self.delegate_to_metadata(*names)
names.each do |name|
define_method name do
metadata[:example_group][name]
end
end
end
def description
description = metadata[:example_group][:description]
RSpec.configuration.format_docstrings_block.call(description)
end
delegate_to_metadata :described_class, :file_path
alias_method :display_name, :description
# @private
alias_method :describes, :described_class
# @private
# @macro [attach] define_example_method
# @param [String] name
# @param [Hash] extra_options
# @param [Block] implementation
# @yield [Example] the example object
def self.define_example_method(name, extra_options={})
define_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)
# Metadata inheritance normally happens in `Example#initialize`,
# but for `:pending` specifically we need it earlier.
pending_metadata = options[:pending] || metadata[:pending]
if pending_metadata
options, block = ExampleGroup.pending_metadata_and_block_for(
options.merge(:pending => pending_metadata),
block
)
end
examples << RSpec::Core::Example.new(self, desc, options, block)
examples.last
end
end
def pending_metadata_and_block_for(options, block)
if String === options[:pending]
reason = options[:pending]
else
options[:pending] = true
reason = RSpec::Core::Pending::NO_REASON_GIVEN
end
# This will fail if no block is provided, which is effectively the
# same as failing the example so it will be marked correctly as
# pending.
callback = Proc.new { pending(reason); instance_exec(&block) }
return options, callback
end
# Defines an example within a group.
# @example
# example do
# end
#
# example "does something" do
# end
#
# example "does something", :with => 'additional metadata' do
# end
#
# example "does something" do |ex|
# # ex is the Example object that evals this block
# end
define_example_method :example
# Defines an example within a group.
# @example
define_example_method :it
# Defines an example within a group.
# This is here primarily for backward compatibility with early versions
# of RSpec which used `context` and `specify` instead of `describe` and
# `it`.
define_example_method :specify
# Shortcut to define an example with `:focus` => true
# @see example
define_example_method :focus, :focused => true, :focus => true
# Shortcut to define an example with `:focus` => true
# @see example
define_example_method :focused, :focused => true, :focus => true
# Shortcut to define an example with `:focus` => true
# @see example
define_example_method :fit, :focused => true, :focus => true
# Shortcut to define an example with :skip => 'Temporarily skipped with xexample'
# @see example
define_example_method :xexample, :skip => 'Temporarily skipped with xexample'
# Shortcut to define an example with :skip => 'Temporarily skipped with xit'
# @see example
define_example_method :xit, :skip => 'Temporarily skipped with xit'
# Shortcut to define an example with :skip => 'Temporarily skipped with xspecify'
# @see example
define_example_method :xspecify, :skip => 'Temporarily skipped with xspecify'
# Shortcut to define an example with :skip => true
# @see example
define_example_method :skip, :skip => true
# Shortcut to define an example with :pending => true
# @see example
define_example_method :pending, :pending => true
# Works like `alias_method :name, :example` with the added benefit of
# assigning default metadata to the generated example.
#
# @note Use with caution. This extends the language used in your
# specs, but does not add any additional documentation. We use this
# in rspec to define methods like `focus` and `xit`, but we also add
# docs for those methods.
def alias_example_to name, extra={}
(class << self; self; end).define_example_method name, extra
end
# @private
# @macro [attach] alias_example_group_to
# @scope class
# @param [String] docstring The example group doc string
# @param [Hash] metadata Additional metadata to attach to the example group
# @yield The example group definition
def alias_example_group_to(name, metadata={})
(class << self; self; end).__send__(:define_method, name) do |*args, &block|
combined_metadata = metadata.dup
combined_metadata.merge!(args.pop) if args.last.is_a? Hash
args << combined_metadata
example_group(*args, &block)
end
RSpec::Core::DSL.expose_example_group_alias(name)
end
# @private
# @macro [attach] define_nested_shared_group_method
#
# @see SharedExampleGroup
def self.define_nested_shared_group_method(new_name, report_label="it should behave like")
define_method(new_name) do |name, *args, &customization_block|
group = example_group("#{report_label} #{name}") do
find_and_eval_shared("examples", name, *args, &customization_block)
end
group.metadata[:shared_group_name] = name
group
end
end
# Generates a nested example group and includes the shared content
# mapped to `name` in the nested group.
define_nested_shared_group_method :it_behaves_like, "behaves like"
# Generates a nested example group and includes the shared content
# mapped to `name` in the nested group.
define_nested_shared_group_method :it_should_behave_like
# Works like `alias_method :name, :it_behaves_like` with the added
# benefit of assigning default metadata to the generated example.
#
# @note Use with caution. This extends the language used in your
# specs, but does not add any additional documentation. We use this
# in rspec to define `it_should_behave_like` (for backward
# compatibility), but we also add docs for that method.
def alias_it_behaves_like_to name, *args, &block
(class << self; self; end).define_nested_shared_group_method name, *args, &block
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
def self.include_context(name, *args, &block)
find_and_eval_shared("context", name, *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
def self.include_examples(name, *args, &block)
find_and_eval_shared("examples", name, *args, &block)
end
# @private
def self.find_and_eval_shared(label, name, *args, &customization_block)
raise ArgumentError, "Could not find shared #{label} #{name.inspect}" unless
shared_block = shared_example_groups[name]
module_exec(*args, &shared_block)
module_eval(&customization_block) if customization_block
end
# @private
def self.examples
@examples ||= []
end
# @private
def self.filtered_examples
world.filtered_examples[self]
end
# @private
def self.descendant_filtered_examples
@descendant_filtered_examples ||= filtered_examples + children.inject([]){|l,c| l + c.descendant_filtered_examples}
end
# The [Metadata](Metadata) object associated with this group.
# @see Metadata
def self.metadata
@metadata if defined?(@metadata)
end
# @private
# @return [Metadata] belonging to the parent of a nested {ExampleGroup}
def self.superclass_metadata
@superclass_metadata ||= self.superclass.respond_to?(:metadata) ? self.superclass.metadata : nil
end
# Generates a subclass of this example group which inherits
# everything except the examples themselves.
#
# ## Examples
#
# 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 }
#
# describe "attribute (of something)" do
# # examples in the group get the before hook
# # declared above, and can access `thing`
# end
# end
#
# @see DSL#describe
def self.example_group(*args, &example_group_block)
args << {} unless args.last.is_a?(Hash)
args.last.update(:example_group_block => example_group_block)
child = subclass(self, args, &example_group_block)
children << child
child
end
# An alias of `example_group`. Generally used when grouping
# examples by a thing you are describing (e.g. an object, class or method).
# @see example_group
alias_example_group_to :describe
# An alias of `example_group`. Generally used when grouping examples
# contextually.
# @see example_group
alias_example_group_to :context
# Shortcut to temporarily make an example group pending.
# @see example_group
alias_example_group_to :xdescribe, :skip => "Temporarily skipped with xdescribe"
# Shortcut to temporarily make an example group pending.
# @see example_group
alias_example_group_to :xcontext, :skip => "Temporarily skipped with xcontext"
# Shortcut to define an example group with `:focus` => true
# @see example_group
alias_example_group_to :fdescribe, :focus => true, :focused => true
# Shortcut to define an example group with `:focus` => true
# @see example_group
alias_example_group_to :fcontext, :focus => true, :focused => true
# @private
def self.subclass(parent, args, &example_group_block)
subclass = Class.new(parent)
subclass.set_it_up(*args)
ExampleGroups.assign_const(subclass)
subclass.module_eval(&example_group_block) if example_group_block
# The LetDefinitions module must be included _after_ other modules
# to ensure that it takes precendence 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
def self.children
@children ||= []
end
# @private
def self.descendants
@_descendants ||= [self] + children.inject([]) {|list, c| list + c.descendants}
end
## @private
def self.parent_groups
@parent_groups ||= ancestors.select {|a| a < RSpec::Core::ExampleGroup}
end
# @private
def self.top_level?
@top_level ||= superclass == ExampleGroup
end
# @private
def self.ensure_example_groups_are_configured
unless defined?(@@example_groups_configured)
RSpec.configuration.configure_mock_framework
RSpec.configuration.configure_expectation_framework
@@example_groups_configured = true
end
end
# @private
def self.set_it_up(*args)
# 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
symbol_description = args.shift if args.first.is_a?(Symbol)
args << Metadata.build_hash_from(args)
args.unshift(symbol_description) if symbol_description
@metadata = RSpec::Core::Metadata.new(superclass_metadata).process(*args)
@order = nil
hooks.register_globals(self, RSpec.configuration.hooks)
world.configure_group(self)
end
# @private
def self.before_all_ivars
@before_all_ivars ||= {}
end
# @private
def self.store_before_all_ivars(example_group_instance)
return if example_group_instance.instance_variables.empty?
example_group_instance.instance_variables.each { |ivar|
before_all_ivars[ivar] = example_group_instance.instance_variable_get(ivar)
}
end
# @private
def self.run_before_all_hooks(example_group_instance)
return if descendant_filtered_examples.empty?
begin
set_ivars(example_group_instance, superclass.before_all_ivars)
AllHookMemoizedHash::Before.isolate_for_all_hook(example_group_instance) do
hooks.run(:before, :all, example_group_instance)
end
ensure
store_before_all_ivars(example_group_instance)
end
end
# @private
def self.run_after_all_hooks(example_group_instance)
return if descendant_filtered_examples.empty?
set_ivars(example_group_instance, before_all_ivars)
AllHookMemoizedHash::After.isolate_for_all_hook(example_group_instance) do
hooks.run(:after, :all, example_group_instance)
end
end
# Runs all the examples in this group
def self.run(reporter)
if RSpec.wants_to_quit
RSpec.clear_remaining_example_groups if top_level?
return
end
reporter.example_group_started(self)
begin
run_before_all_hooks(new)
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) }
rescue Exception => ex
RSpec.wants_to_quit = true if fail_fast?
for_filtered_examples(reporter) {|example| example.fail_with_exception(reporter, ex) }
ensure
run_after_all_hooks(new)
before_all_ivars.clear
reporter.example_group_finished(self)
end
end
# @private
def self.ordering_strategy
order = metadata.fetch(:order, :global)
registry = RSpec.configuration.ordering_registry
registry.fetch(order) do
warn <<-WARNING.gsub(/^ +\|/, '')
|WARNING: Ignoring unknown ordering specified using `:order => #{order.inspect}` metadata.
| Falling back to configured global ordering.
| Unrecognized ordering specified at: #{metadata[:example_group][:location]}
WARNING
registry.fetch(:global)
end
end
# @private
def self.run_examples(reporter)
ordering_strategy.order(filtered_examples).map do |example|
next if RSpec.wants_to_quit
instance = new
set_ivars(instance, before_all_ivars)
succeeded = example.run(instance, reporter)
RSpec.wants_to_quit = true if fail_fast? && !succeeded
succeeded
end.all?
end
# @private
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
# @private
def self.fail_fast?
RSpec.configuration.fail_fast?
end
# @private
def self.any_apply?(filters)
metadata.any_apply?(filters)
end
# @private
def self.all_apply?(filters)
metadata.all_apply?(filters)
end
# @private
def self.declaration_line_numbers
@declaration_line_numbers ||= [metadata[:example_group][:line_number]] +
examples.collect {|e| e.metadata[:line_number]} +
children.inject([]) {|l,c| l + c.declaration_line_numbers}
end
# @private
def self.top_level_description
parent_groups.last.description
end
# @private
def self.set_ivars(instance, ivars)
ivars.each {|name, value| instance.instance_variable_set(name, value)}
end
# 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
#
#
def described_class
self.class.described_class
end
# @private
# instance_evals the block, capturing and reporting an exception if
# raised
def instance_exec_with_rescue(example, context = nil, &hook)
begin
instance_exec(example, &hook)
rescue Exception => e
if RSpec.current_example
RSpec.current_example.set_exception(e, context)
else
raise
end
end
end
end
end
# Namespace for the example group subclasses generated by top-level `describe`.
module ExampleGroups
def self.assign_const(group)
base_name = base_name_for(group)
const_scope = constant_scope_for(group)
name = disambiguate(base_name, const_scope)
const_scope.const_set(name, group)
end
def self.constant_scope_for(group)
const_scope = group.superclass
const_scope = self if const_scope == Core::ExampleGroup
const_scope
end
def self.base_name_for(group)
return "Anonymous" if group.description.empty?
# convert to CamelCase
name = ' ' + group.description
name.gsub!(/[^0-9a-zA-Z]+([0-9a-zA-Z])/) { $1.upcase }
name.lstrip! # Remove leading whitespace
name.gsub!(/\W/, '') # JRuby, RBX and others don't like non-ascii in const names
# Ruby requires first const letter to be A-Z. Use `Nested`
# as necessary to enforce that.
name.gsub!(/\A([^A-Z]|\z)/, 'Nested\1')
name
end
def self.disambiguate(name, const_scope)
return name unless const_scope.const_defined?(name)
# Add a trailing number if needed to disambiguate from an existing constant.
name << "_2"
name.next! while const_scope.const_defined?(name)
name
end
end
end