Quick vs Lettuce comparison of testing frameworks
What are the differences between Quick and Lettuce?

Quick

https://github.com/quick/quick

Lettuce

https://pypi.org/project/lettuce/
Programming language

Swift

Python

Category

Acceptance Testing, Unit Testing

Unit Testing, Acceptance Testing

General info

Quick is a Swift (and Objective-C) testing framework.

Quick is a behavior-driven development framework for Swift and Objective-C that is inspired by RSpec, Specta, and Ginkgo. Quick comes bundled with Nimble a matcher framework for your tests.

Lettuce is a BDD testing tool for Python

Lettuce is a testing tool for Python which is inspired by Ruby's Cucumber that supports Gherkin. It can execute plain-text functional descriptions as automated tests for Python projects just like Cucumber does for Ruby
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

Yes

Yes, it is an xUnit style test framework

No

However It can generate xml results for behaviour tests xUnit style
Client-side
Allows testing code execution on the client, such as a web browser

Yes

Developers can test front-end behaviour and components by defining front-end feature specifications

Yes

By integrating Lettuce with Selenium’s Python bindings, you have a robust framework for testing Django applications. It can test front-end behaviour
Server-side
Allows testing the bahovior of a server-side code

Yes

Developers can test back-end behaviour and components by defining back-end feature specifications

Yes

Lettuce can test various server and database behaviours and interactions
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Quick contains fixture methods setup() and teardown() for setting up and destroying test environments

N/A

Group fixtures
Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.

Yes

Yes, example groups (logical groupings of examples/tests) can share setup and teardown code

N/A

Generators
Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.

N/A

Yes

By using a third party library
Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

Unknown

Mocks
Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)

Yes

Yes, developers can create mock objects with Quick using the Cuckoo library

By adding the lettuce-tools library one has access to the Mock module to implement a configurable http REST mock.
Grouping
Allows organizing tests in groups

Yes

In Quick test suites are named Specs, and every test suite you create starts off with a class inheriting from QuickSpec includes a main method, spec() which contains all the test cases.

Yes

It allows grouping of tests
Other
Other useful information about the testing framework