Why Testo?

Testo (pronounced [test-oh], meaning "dough" in many languages) is an extensible testing framework for PHP. Built for scenarios requiring complete customization of the testing process: SDKs, framework tools, complex integrations.

Unlike other testing frameworks, Testo provides everything at once: familiar and convenient PHP syntax, unprecedented extensibility and customizability, and a simple yet powerful architecture based on a minimal core and middleware system.

You can mold it into any testing infrastructure you need.

History

Testo was born from the need for an extensible testing framework that could adapt to the complex requirements of modern PHP projects. In brief:

• Previously, to wrap test execution with custom logic, we relied on overriding the TestCase::runTest() method, which, although marked with @internal annotation, had existed for many years without semantic changes. It was a perfect extension point.
• However, in versions 10.5.46, 11, and 12, this method became private.
• Appeals to maintainers don't work. Even these ones.
• PEST also faced this problem. What did they do? Simply overrode some PHPUnit classes in their own namespace. But this is a fragile solution, so PEST additionally set conflicts in composer.json to prevent breaking PHPUnit updates.

Testo Philosophy

Developer's Full Control

From Testo's perspective, tests are the developer's property, not the framework's. All metadata and operational data needed by the framework are stored and processed separately.

Therefore:

• Test classes don't need to extend TestCase
• Test cases don't run themselves and don't even know their name in the test environment
• You can use the constructor however you want
• Tests can even be ordinary functions!

#[Test]
function simpleTest(): void
{
    Assert::true(true);
}

Extensibility

Testo is built on a simple idea: a small core with a set of DTOs and contracts, and all functionality is built on top of middleware and event system.

The core simply builds several pipelines from middleware, and then do whatever you want. Every framework feature is middleware or event handlers:

• Attributes in general
• Data providers
• Inline testing
• Assertion system (Assert, Expect)
• CLI rendering and TeamCity

Well-Designed API

Instead of a bloated Assert facade with ~2300 lines (as in PHPUnit), Testo provides:

• Assert — for assertions (checked here and now)
• Expect — for expectations (checked after test completion)
• Pipe assertions — grouping by types for cleaner code:

// Strings
Assert::string($string)->contains("str");

// Files
Assert::file("foo.txt")->notExists();

// Exceptions
Expect::exception(Failure::class)
    ->fromMethod(Service::class, 'process')
    ->withMessage("foo bar");

Testo comes with a PhpStorm/IntelliJ IDEA plugin that provides all the familiar functionality including test running, navigation, and debugging.

Who Is Testo For?

Testo is built for those who:

• Develop frameworks and need deep test integration.
• Create SDKs with specific testing requirements.
• Build complex systems where PHPUnit doesn't provide the needed flexibility.
• Want full control over testing infrastructure.
• Prefer PHP syntax over JS.

What's Next?

Testo is in active development and moving toward version 1.0.0. We're open to ideas and suggestions from the community.

Join the development on GitHub.

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We believe developers should have full control over their testing environment, and Testo delivers exactly that.