module Spectator::Mock

Overview

Module providing macros for defining new mocks from existing types and injecting mock features into concrete types.

Defined in:

spectator/mocks/mock.cr

Macro Summary

Macro Detail

macro define_subtype(base, mocked_type, type_name, name = nil, **value_methods, &block) #

Defines a type that inherits from another, existing type. The newly defined subtype will have mocking functionality.

Methods from the inherited type will be overridden to support stubs. base is the keyword for the type being defined - class or struct. mocked_type is the original type to inherit from. type_name is the name of the new type to define. An optional name of the mock can be provided. Any key-value pairs provided with value_methods are used as initial stubs for the mocked type.

A block can be provided to define additional methods and stubs. The block is evaluated in the context of the derived type.

Mock.define_subtype(:class, SomeType, meth1: 42, meth2: "foobar") do
  stub abstract def meth3 : Symbol

  # Default implementation with a dynamic value.
  stub def meth4
    Time.utc
  end
end

[View source]
macro inject(base, type_name, name = nil, **value_methods, &block) #

Injects mock functionality into an existing type.

Generally this method of mocking should be avoiding. It modifies types being tested, the mock functionality won't exist outside of tests. This option should only be used when sub-types are not possible (e.g. concrete struct).

Methods in the type will be overridden to support stubs. The original method functionality will still be accessible, but pass through mock code first. base is the keyword for the type being defined - class or struct. type_name is the name of the type to inject mock functionality into. This must be full, resolvable path to the type. An optional name of the mock can be provided. Any key-value pairs provided with value_methods are used as initial stubs for the mocked type.

A block can be provided to define additional methods and stubs. The block is evaluated in the context of the derived type.

Mock.inject(:struct, SomeType, meth1: 42, meth2: "foobar") do
  stub abstract def meth3 : Symbol

  # Default implementation with a dynamic value.
  stub def meth4
    Time.utc
  end
end

[View source]