In-depth tutorials and comparisons for testing tools and frameworks — Playwright, Cypress, Selenium, Robot Framework, and more.
Test Automation
Spock's built-in mocking eliminates the need for Mockito or PowerMock in most Groovy/Java projects. The API is concise, the error messages are clear, and the interactions integrate directly with the then block's assertion syntax. The Three Types Spock provides three mock variants with distinct purposes:
Test Automation
Hedgehog is a modern property-based testing library for Haskell that addresses QuickCheck's main pain point: shrinking. Where QuickCheck requires manual shrink implementations, Hedgehog shrinks automatically because shrinking is built into the generator itself. The Key Difference from QuickCheck In QuickCheck, generation and shrinking are separate. You write an
Test Automation
Gradle's test task orchestrates JVM test execution with fine-grained control over filtering, parallelism, JVM configuration, and reporting. Understanding how to configure it properly saves significant time in both development and CI. Basic Test Configuration The test task is automatically applied with the java plugin: // build.gradle plugins { id
Test Automation
Geb is a browser automation library for Groovy that combines WebDriver's power with a jQuery-inspired content DSL and Groovy's concise syntax. It integrates naturally with Spock for behavior-driven browser tests. What Geb Provides Geb wraps Selenium WebDriver but adds: * A CSS/jQuery-like content DSL for finding
Test Automation
Replaying production traffic is conceptually simple: capture requests, store them, send them again to a different target. In practice, it is full of hard problems — authentication tokens expire, session state is tied to specific users, database operations are not idempotent, and request timing and ordering matters. This post covers the
Test Automation
Concurrent systems fail in ways that test suites almost never catch. A race condition that corrupts data might require a specific interleaving of 12 operations across 4 threads — a sequence that a random test might hit once in a billion runs, but that a model checker can find in seconds
Test Automation
Distributed systems fail in ways that are nearly impossible to reproduce with conventional tests. Race conditions, partial failures, network partitions, and subtle ordering bugs hide in the gaps between nodes, surfacing only under specific interleavings that happen to occur in production at 3 AM. TLA+ is a formal specification language
Test Automation
Since its launch in 2016, Google's OSS-Fuzz program has found over 10,000 vulnerabilities and bugs in more than 1,000 open source projects. It runs fuzzing continuously, 24 hours a day, across billions of CPU-core-hours of compute. When it finds a crash, it automatically files an issue,
Test Automation
The most realistic test data you will ever have is the traffic that hits your production service right now. Real users make requests with edge-case inputs, unusual character sets, unexpected header combinations, and query patterns that no test author would ever think to write. GoReplay (gor) is an open-source tool
Test Automation
Twitter's engineering team faced a problem that scales with complexity: every time they deployed a new version of a service, they needed to verify it produced the same responses as the old version across the enormous variety of real-world requests that hit their platform. Writing test cases manually
Test Automation
Dark launch is the practice of running a new version of a service in production — receiving real requests, doing real work — while still serving responses from the current version. Users see nothing different. Your new service processes every request, you measure its behavior, and only when you are confident does
Test Automation
Java has a reputation for safety — garbage collection eliminates entire classes of memory bugs, strong typing prevents many type errors, and the JVM sandboxes execution. But Java applications can still have serious bugs: path traversal vulnerabilities in file handling, deserialization exploits, XML/JSON parsing crashes, SQL injection through improperly sanitized