Dirty Tests And How To Clean Them

Are your tests a maintenance nightmare? Learn to apply clean code principles and transform them into a valuable, readable asset.

#1about 5 minutes

Why test code is often treated differently

Test code is often neglected because developers don't expect to revisit it and frequently copy-paste existing tests, duplicating code smells.

#2about 1 minute

The developer's job is writing maintainable code

The primary goal of a developer is to write code that works repeatedly, and clean code principles reduce maintenance time.

#3about 7 minutes

Defining clean code as communication with others

Clean code is simple, direct, and written like prose because it is primarily a form of communication between programmers.

#4about 6 minutes

Key attributes of clean and effective tests

Clean tests clearly show their intent, are focused on a single scenario, and use abstraction to separate domain logic from framework details.

#5about 4 minutes

Identifying common code smells in test suites

Common anti-patterns in tests include God classes, unhelpful comments, poor naming, and the use of magic numbers without context.

#6about 5 minutes

Refactoring duplicated code with a common setup

The first refactoring step involves moving duplicated variable initializations from individual tests into a common setup method.

#7about 4 minutes

Improving names and extracting helper methods

Further refactoring involves creating more descriptive test names, extracting repeated API call logic into a helper method, and using production constants to build robust URLs.

#8about 4 minutes

Using the builder pattern for test data setup

The Builder pattern simplifies the creation of complex data objects for tests by handling default values and making unique parameters more visible.

#9about 2 minutes

Separating concerns with an API call wrapper

Create an abstraction layer like an API call wrapper to separate low-level HTTP and JSON logic from the high-level domain language of the tests.

#10about 5 minutes

Signaling intent with descriptive constant names

Use named constants like `ANY_NUMBER` versus specific values to signal to the reader which test inputs are arbitrary and which are significant for the scenario.

#11about 3 minutes

Discussing hierarchical test classes and organization

Hierarchical test classes can be useful, but it is often better to favor composition over inheritance to avoid creating brittle test structures that are hard to change.

#12about 8 minutes

Career advice on starting in testing and consulting

Starting a career in testing provides a valuable mindset shift for building quality software, and self-employment offers flexibility but requires stepping out of one's comfort zone.