Module: ThoughtBot::Shoulda::ActiveRecord::Macros

Includes:
MacroHelpers
Included in:
Test::Unit::TestCase
Defined in:
lib/shoulda/active_record/macros.rb

Overview

Macro test helpers for your active record models

These helpers will test most of the validations and associations for your ActiveRecord models.

class UserTest < Test::Unit::TestCase
  should_require_attributes :name, :phone_number
  should_not_allow_values_for :phone_number, "abcd", "1234"
  should_allow_values_for :phone_number, "(123) 456-7890"

  should_protect_attributes :password

  should_have_one :profile
  should_have_many :dogs
  should_have_many :messes, :through => :dogs
  should_belong_to :lover
end

For all of these helpers, the last parameter may be a hash of options.

Instance Method Summary collapse

Methods included from MacroHelpers

#default_error_message

Instance Method Details

#load_all_fixtures ⇒ Object

DEPRECATED: Use fixtures :all instead

Loads all fixture files (test/fixtures/*.yml)



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# File 'lib/shoulda/active_record/macros.rb', line 46

def load_all_fixtures
  warn "[DEPRECATION] load_all_fixtures is deprecated.  Use `fixtures :all` instead."
  fixtures :all
end

#should_allow_values_for(attribute, *good_values) ⇒ Object

Ensures that the attribute can be set to the given values.

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Example:

should_allow_values_for :isbn, "isbn 1 2345 6789 0", "ISBN 1-2345-6789-0"



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# File 'lib/shoulda/active_record/macros.rb', line 204

def should_allow_values_for(attribute, *good_values)
  get_options!(good_values)
  klass = model_class
  good_values.each do |v|
    should "allow #{attribute} to be set to #{v.inspect}" do
      assert_good_value(klass, attribute, v)
    end
  end
end

#should_belong_to(*associations) ⇒ Object

Ensure that the belongs_to relationship exists.

should_belong_to :parent



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# File 'lib/shoulda/active_record/macros.rb', line 528

def should_belong_to(*associations)
  get_options!(associations)
  klass = model_class
  associations.each do |association|
    should "belong_to #{association}" do
      reflection = klass.reflect_on_association(association)
      assert reflection, "#{klass.name} does not have any relationship to #{association}"
      assert_equal :belongs_to, reflection.macro

      unless reflection.options[:polymorphic]
        associated_klass = (reflection.options[:class_name] || association.to_s.camelize).constantize
        fk = reflection.options[:foreign_key] || reflection.primary_key_name
        assert klass.column_names.include?(fk.to_s), "#{klass.name} does not have a #{fk} foreign key."
      end
    end
  end
end

#should_ensure_length_at_least(attribute, min_length, opts = {}) ⇒ Object

Ensures that the length of the attribute is at least a certain length

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :short_message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.too_short') % min_length

Example:

should_ensure_length_at_least :name, 3



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# File 'lib/shoulda/active_record/macros.rb', line 279

def should_ensure_length_at_least(attribute, min_length, opts = {})
  short_message = get_options!([opts], :short_message)
  short_message ||= default_error_message(:too_short, :count => min_length)

  klass = model_class

  if min_length > 0
    min_value = "x" * (min_length - 1)
    should "not allow #{attribute} to be less than #{min_length} chars long" do
      assert_bad_value(klass, attribute, min_value, short_message)
    end
  end
  should "allow #{attribute} to be at least #{min_length} chars long" do
    valid_value = "x" * (min_length)
    assert_good_value(klass, attribute, valid_value, short_message)
  end
end

#should_ensure_length_in_range(attribute, range, opts = {}) ⇒ Object

Ensures that the length of the attribute is in the given range

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :short_message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.too_short') % range.first

  • :long_message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.too_long') % range.last

Example:

should_ensure_length_in_range :password, (6..20)



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# File 'lib/shoulda/active_record/macros.rb', line 229

def should_ensure_length_in_range(attribute, range, opts = {})
  short_message, long_message = get_options!([opts], :short_message, :long_message)
  short_message ||= default_error_message(:too_short, :count => range.first)
  long_message  ||= default_error_message(:too_long, :count => range.last)

  klass = model_class
  min_length = range.first
  max_length = range.last
  same_length = (min_length == max_length)

  if min_length > 0
    should "not allow #{attribute} to be less than #{min_length} chars long" do
      min_value = "x" * (min_length - 1)
      assert_bad_value(klass, attribute, min_value, short_message)
    end
  end

  if min_length > 0
    should "allow #{attribute} to be exactly #{min_length} chars long" do
      min_value = "x" * min_length
      assert_good_value(klass, attribute, min_value, short_message)
    end
  end

  should "not allow #{attribute} to be more than #{max_length} chars long" do
    max_value = "x" * (max_length + 1)
    assert_bad_value(klass, attribute, max_value, long_message)
  end

  unless same_length
    should "allow #{attribute} to be exactly #{max_length} chars long" do
      max_value = "x" * max_length
      assert_good_value(klass, attribute, max_value, long_message)
    end
  end
end

#should_ensure_length_is(attribute, length, opts = {}) ⇒ Object

Ensures that the length of the attribute is exactly a certain length

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.wrong_length') % length

Example:

should_ensure_length_is :ssn, 9



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# File 'lib/shoulda/active_record/macros.rb', line 310

def should_ensure_length_is(attribute, length, opts = {})
  message = get_options!([opts], :message)
  message ||= default_error_message(:wrong_length, :count => length)

  klass = model_class

  should "not allow #{attribute} to be less than #{length} chars long" do
    min_value = "x" * (length - 1)
    assert_bad_value(klass, attribute, min_value, message)
  end

  should "not allow #{attribute} to be greater than #{length} chars long" do
    max_value = "x" * (length + 1)
    assert_bad_value(klass, attribute, max_value, message)
  end

  should "allow #{attribute} to be #{length} chars long" do
    valid_value = "x" * (length)
    assert_good_value(klass, attribute, valid_value, message)
  end
end

#should_ensure_value_in_range(attribute, range, opts = {}) ⇒ Object

Ensure that the attribute is in the range specified

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :low_message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.inclusion')

  • :high_message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.inclusion')

Example:

should_ensure_value_in_range :age, (0..100)



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# File 'lib/shoulda/active_record/macros.rb', line 347

def should_ensure_value_in_range(attribute, range, opts = {})
  low_message, high_message = get_options!([opts], :low_message, :high_message)
  low_message  ||= default_error_message(:inclusion)
  high_message ||= default_error_message(:inclusion)

  klass = model_class
  min   = range.first
  max   = range.last

  should "not allow #{attribute} to be less than #{min}" do
    v = min - 1
    assert_bad_value(klass, attribute, v, low_message)
  end

  should "allow #{attribute} to be #{min}" do
    v = min
    assert_good_value(klass, attribute, v, low_message)
  end

  should "not allow #{attribute} to be more than #{max}" do
    v = max + 1
    assert_bad_value(klass, attribute, v, high_message)
  end

  should "allow #{attribute} to be #{max}" do
    v = max
    assert_good_value(klass, attribute, v, high_message)
  end
end

#should_have_and_belong_to_many(*associations) ⇒ Object

Ensures that the has_and_belongs_to_many relationship exists, and that the join table is in place.

should_have_and_belong_to_many :posts, :cars



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# File 'lib/shoulda/active_record/macros.rb', line 509

def should_have_and_belong_to_many(*associations)
  get_options!(associations)
  klass = model_class

  associations.each do |association|
    should "should have and belong to many #{association}" do
      reflection = klass.reflect_on_association(association)
      assert reflection, "#{klass.name} does not have any relationship to #{association}"
      assert_equal :has_and_belongs_to_many, reflection.macro
      table = reflection.options[:join_table]
      assert ::ActiveRecord::Base.connection.tables.include?(table.to_s), "table #{table} doesn't exist"
    end
  end
end

#should_have_class_methods(*methods) ⇒ Object

Ensure that the given class methods are defined on the model.

should_have_class_methods :find, :destroy



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# File 'lib/shoulda/active_record/macros.rb', line 550

def should_have_class_methods(*methods)
  get_options!(methods)
  klass = model_class
  methods.each do |method|
    should "respond to class method ##{method}" do
      assert_respond_to klass, method, "#{klass.name} does not have class method #{method}"
    end
  end
end

#should_have_db_column(name, opts = {}) ⇒ Object

Ensure that the given column is defined on the models backing SQL table. The options are the same as the instance variables defined on the column definition: :precision, :limit, :default, :null, :primary, :type, :scale, and :sql_type.

should_have_db_column :email, :type => "string", :default => nil,   :precision => nil, :limit    => 255,
                              :null => true,     :primary => false, :scale     => nil, :sql_type => 'varchar(255)'



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# File 'lib/shoulda/active_record/macros.rb', line 598

def should_have_db_column(name, opts = {})
  klass = model_class
  test_name = "have column named :#{name}"
  test_name += " with options " + opts.inspect unless opts.empty?
  should test_name do
    column = klass.columns.detect {|c| c.name == name.to_s }
    assert column, "#{klass.name} does not have column #{name}"
    opts.each do |k, v|
      assert_equal column.instance_variable_get("@#{k}").to_s, v.to_s, ":#{name} column on table for #{klass} does not match option :#{k}"
    end
  end
end

#should_have_db_columns(*columns) ⇒ Object

Ensure that the given columns are defined on the models backing SQL table.

should_have_db_columns :id, :email, :name, :created_at



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# File 'lib/shoulda/active_record/macros.rb', line 578

def should_have_db_columns(*columns)
  column_type = get_options!(columns, :type)
  klass = model_class
  columns.each do |name|
    test_name = "have column #{name}"
    test_name += " of type #{column_type}" if column_type
    should test_name do
      column = klass.columns.detect {|c| c.name == name.to_s }
      assert column, "#{klass.name} does not have column #{name}"
    end
  end
end

#should_have_indices(*columns) ⇒ Object Also known as: should_have_index

Ensures that there are DB indices on the given columns or tuples of columns. Also aliased to should_have_index for readability

should_have_indices :email, :name, [:commentable_type, :commentable_id]
should_have_index :age



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# File 'lib/shoulda/active_record/macros.rb', line 617

def should_have_indices(*columns)
  table = model_class.table_name
  indices = ::ActiveRecord::Base.connection.indexes(table).map(&:columns)

  columns.each do |column|
    should "have index on #{table} for #{column.inspect}" do
      columns = [column].flatten.map(&:to_s)
      assert_contains(indices, columns)
    end
  end
end

#should_have_instance_methods(*methods) ⇒ Object

Ensure that the given instance methods are defined on the model.

should_have_instance_methods :email, :name, :name=



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# File 'lib/shoulda/active_record/macros.rb', line 564

def should_have_instance_methods(*methods)
  get_options!(methods)
  klass = model_class
  methods.each do |method|
    should "respond to instance method ##{method}" do
      assert_respond_to klass.new, method, "#{klass.name} does not have instance method #{method}"
    end
  end
end

#should_have_many(*associations) ⇒ Object

Ensures that the has_many relationship exists. Will also test that the associated table has the required columns. Works with polymorphic associations.

Options:

  • :through - association name for has_many :through

  • :dependent - tests that the association makes use of the dependent option.

Example:

should_have_many :friends
should_have_many :enemies, :through => :friends
should_have_many :enemies, :dependent => :destroy



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# File 'lib/shoulda/active_record/macros.rb', line 415

def should_have_many(*associations)
  through, dependent = get_options!(associations, :through, :dependent)
  klass = model_class
  associations.each do |association|
    name = "have many #{association}"
    name += " through #{through}" if through
    name += " dependent => #{dependent}" if dependent
    should name do
      reflection = klass.reflect_on_association(association)
      assert reflection, "#{klass.name} does not have any relationship to #{association}"
      assert_equal :has_many, reflection.macro

      if through
        through_reflection = klass.reflect_on_association(through)
        assert through_reflection, "#{klass.name} does not have any relationship to #{through}"
        assert_equal(through, reflection.options[:through])
      end

      if dependent
        assert_equal dependent.to_s,
                     reflection.options[:dependent].to_s,
                     "#{association} should have #{dependent} dependency"
      end

      # Check for the existence of the foreign key on the other table
      unless reflection.options[:through]
        if reflection.options[:foreign_key]
          fk = reflection.options[:foreign_key]
        elsif reflection.options[:as]
          fk = reflection.options[:as].to_s.foreign_key
        else
          fk = reflection.primary_key_name
        end

        associated_klass_name = (reflection.options[:class_name] || association.to_s.classify)
        associated_klass = associated_klass_name.constantize

        assert associated_klass.column_names.include?(fk.to_s),
               "#{associated_klass.name} does not have a #{fk} foreign key."
      end
    end
  end
end

#should_have_named_scope(scope_call, *args) ⇒ Object

Ensures that the model has a method named scope_name that returns a NamedScope object with the proxy options set to the options you supply. scope_name can be either a symbol, or a method call which will be evaled against the model. The eval’d method call has access to all the same instance variables that a should statement would.

Options: Any of the options that the named scope would pass on to find.

Example:

should_have_named_scope :visible, :conditions => {:visible => true}

Passes for

named_scope :visible, :conditions => {:visible => true}

Or for

def self.visible
  scoped(:conditions => {:visible => true})
end

You can test lambdas or methods that return ActiveRecord#scoped calls:

should_have_named_scope 'recent(5)', :limit => 5
should_have_named_scope 'recent(1)', :limit => 1

Passes for

named_scope :recent, lambda {|c| {:limit => c}}

Or for

def self.recent(c)
  scoped(:limit => c)
end



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# File 'lib/shoulda/active_record/macros.rb', line 691

def should_have_named_scope(scope_call, *args)
  klass = model_class
  scope_opts = args.extract_options!
  scope_call = scope_call.to_s

  context scope_call do
    setup do
      @scope = eval("#{klass}.#{scope_call}")
    end

    should "return a scope object" do
      assert_equal ::ActiveRecord::NamedScope::Scope, @scope.class
    end

    unless scope_opts.empty?
      should "scope itself to #{scope_opts.inspect}" do
        assert_equal scope_opts, @scope.proxy_options
      end
    end
  end
end

#should_have_one(*associations) ⇒ Object

Ensure that the has_one relationship exists. Will also test that the associated table has the required columns. Works with polymorphic associations.

Options:

  • :dependent - tests that the association makes use of the dependent option.

Example:

should_have_one :god # unless hindu



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# File 'lib/shoulda/active_record/macros.rb', line 469

def should_have_one(*associations)
  dependent = get_options!(associations, :dependent)
  klass = model_class
  associations.each do |association|
    name = "have one #{association}"
    name += " dependent => #{dependent}" if dependent
    should name do
      reflection = klass.reflect_on_association(association)
      assert reflection, "#{klass.name} does not have any relationship to #{association}"
      assert_equal :has_one, reflection.macro

      associated_klass = (reflection.options[:class_name] || association.to_s.camelize).constantize

      if reflection.options[:foreign_key]
        fk = reflection.options[:foreign_key]
      elsif reflection.options[:as]
        fk = reflection.options[:as].to_s.foreign_key
        fk_type = fk.gsub(/_id$/, '_type')
        assert associated_klass.column_names.include?(fk_type),
               "#{associated_klass.name} does not have a #{fk_type} column."
      else
        fk = klass.name.foreign_key
      end
      assert associated_klass.column_names.include?(fk.to_s),
             "#{associated_klass.name} does not have a #{fk} foreign key."

      if dependent
        assert_equal dependent.to_s,
                     reflection.options[:dependent].to_s,
                     "#{association} should have #{dependent} dependency"
      end
    end
  end
end

#should_have_readonly_attributes(*attributes) ⇒ Object

Ensures that the attribute cannot be changed once the record has been created.

should_have_readonly_attributes :password, :admin_flag



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# File 'lib/shoulda/active_record/macros.rb', line 154

def should_have_readonly_attributes(*attributes)
  get_options!(attributes)
  klass = model_class

  attributes.each do |attribute|
    attribute = attribute.to_sym
    should "make #{attribute} read-only" do
      readonly = klass.readonly_attributes || []

      assert readonly.include?(attribute.to_s),
             (readonly.empty? ?
               "#{klass} attribute #{attribute} is not read-only" :
               "#{klass} is making #{readonly.to_a.to_sentence} read-only, but not #{attribute}.")
    end
  end
end

#should_not_allow_values_for(attribute, *bad_values) ⇒ Object

Ensures that the attribute cannot be set to the given values

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.invalid')

Example:

should_not_allow_values_for :isbn, "bad 1", "bad 2"



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# File 'lib/shoulda/active_record/macros.rb', line 184

def should_not_allow_values_for(attribute, *bad_values)
  message = get_options!(bad_values, :message)
  message ||= default_error_message(:invalid)
  klass = model_class
  bad_values.each do |v|
    should "not allow #{attribute} to be set to #{v.inspect}" do
      assert_bad_value(klass, attribute, v, message)
    end
  end
end

#should_only_allow_numeric_values_for(*attributes) ⇒ Object

Ensure that the attribute is numeric

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.not_a_number')

Example:

should_only_allow_numeric_values_for :age



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# File 'lib/shoulda/active_record/macros.rb', line 390

def should_only_allow_numeric_values_for(*attributes)
  message = get_options!(attributes, :message)
  message ||= default_error_message(:not_a_number)
  klass = model_class
  attributes.each do |attribute|
    attribute = attribute.to_sym
    should "only allow numeric values for #{attribute}" do
      assert_bad_value(klass, attribute, "abcd", message)
    end
  end
end

#should_protect_attributes(*attributes) ⇒ Object

Ensures that the attribute cannot be set on mass update.

should_protect_attributes :password, :admin_flag



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# File 'lib/shoulda/active_record/macros.rb', line 131

def should_protect_attributes(*attributes)
  get_options!(attributes)
  klass = model_class

  attributes.each do |attribute|
    attribute = attribute.to_sym
    should "protect #{attribute} from mass updates" do
      protected = klass.protected_attributes || []
      accessible = klass.accessible_attributes || []

      assert protected.include?(attribute.to_s) ||
        (!accessible.empty? && !accessible.include?(attribute.to_s)),
             (accessible.empty? ?
               "#{klass} is protecting #{protected.to_a.to_sentence}, but not #{attribute}." :
               "#{klass} has made #{attribute} accessible")
    end
  end
end

#should_require_acceptance_of(*attributes) ⇒ Object

Ensures that the model cannot be saved if one of the attributes listed is not accepted.

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.accepted')

Example:

should_require_acceptance_of :eula



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# File 'lib/shoulda/active_record/macros.rb', line 644

def should_require_acceptance_of(*attributes)
  message = get_options!(attributes, :message)
  message ||= default_error_message(:accepted)
  klass = model_class

  attributes.each do |attribute|
    should "require #{attribute} to be accepted" do
      assert_bad_value(klass, attribute, false, message)
    end
  end
end

#should_require_attributes(*attributes) ⇒ Object

Ensures that the model cannot be saved if one of the attributes listed is not present.

If an instance variable has been created in the setup named after the model being tested, then this method will use that. Otherwise, it will create a new instance to test against.

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.blank')

Example:

should_require_attributes :name, :phone_number



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# File 'lib/shoulda/active_record/macros.rb', line 64

def should_require_attributes(*attributes)
  message = get_options!(attributes, :message)
  message ||= default_error_message(:blank)
  klass = model_class

  attributes.each do |attribute|
    should "require #{attribute} to be set" do
      assert_bad_value(klass, attribute, nil, message)
    end
  end
end

#should_require_unique_attributes(*attributes) ⇒ Object

Ensures that the model cannot be saved if one of the attributes listed is not unique. Requires an existing record

Options:

  • :message - value the test expects to find in errors.on(:attribute). Regexp or string. Default = I18n.translate('activerecord.errors.messages.taken')

  • :scoped_to - field(s) to scope the uniqueness to.

Examples:

should_require_unique_attributes :keyword, :username
should_require_unique_attributes :name, :message => "O NOES! SOMEONE STOELED YER NAME!"
should_require_unique_attributes :email, :scoped_to => :name
should_require_unique_attributes :address, :scoped_to => [:first_name, :last_name]



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# File 'lib/shoulda/active_record/macros.rb', line 90

def should_require_unique_attributes(*attributes)
  message, scope = get_options!(attributes, :message, :scoped_to)
  scope = [*scope].compact
  message ||= default_error_message(:taken)

  klass = model_class
  attributes.each do |attribute|
    attribute = attribute.to_sym
    should "require unique value for #{attribute}#{" scoped to #{scope.join(', ')}" unless scope.blank?}" do
      assert existing = klass.find(:first), "Can't find first #{klass}"
      object = klass.new
      existing_value = existing.send(attribute)

      if !scope.blank?
        scope.each do |s|
          assert_respond_to object, :"#{s}=", "#{klass.name} doesn't seem to have a #{s} attribute."
          object.send("#{s}=", existing.send(s))
        end
      end
      assert_bad_value(object, attribute, existing_value, message)

      # Now test that the object is valid when changing the scoped attribute
      # TODO:  There is a chance that we could change the scoped field
      # to a value that's already taken.  An alternative implementation
      # could actually find all values for scope and create a unique
      # one.
      if !scope.blank?
        scope.each do |s|
          # Assume the scope is a foreign key if the field is nil
          object.send("#{s}=", existing.send(s).nil? ? 1 : existing.send(s).next)
          assert_good_value(object, attribute, existing_value, message)
        end
      end
    end
  end
end