Skip to main content

Mock/Stub/Spy library for Python

Project description

FlexMock provides a mock/stub/spy library for Python.

It is inspired by Ruby’s FlexMock, however full feature parity with the Ruby version is not a goal. Python FlexMock omits a number of things in the Ruby version, mainly various shortcuts for existing functionality, and implements a number of things that Ruby’s FlexMock doesn’t support, such as proxying/spying and matching arguments using their classes in addition to values.

What makes FlexMock unique in the Python testing world is its automatic integration with the test runner, allowing for really terse syntax and avoiding both the action->assertion and record->replay paradigms supported by all the other Python mocking libraries currently available. To be sure, you can still write your assertions in the action->assertion mode using FlexMock, but its powerful syntax allows you to define both the expectation and the assertion at the same time.


  • test runner integration, i.e. automatic expectation checking on tearDown
  • advanced argument matching, including matching types and user-defined classes
  • expectations on number of times called, including at_least/at_most
  • mocks returning custom values, including different values on successive invokations
  • mocks raising custom exceptions
  • simple syntax for generating new mock objects
  • overriding new instances (on new-style objects)
  • parameter shortcuts for even terser syntax
  • proxying/spying using the and_execute expectation modifier
  • mocking a generator using and_yield
  • enforcing expectations ordering



Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for flexmock, version 0.6.8
Filename, size File type Python version Upload date Hashes
Filename, size flexmock-0.6.8.tar.gz (6.7 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page