How to use the command behat (with examples)

Behat is a PHP framework for Behavior-Driven Development (BDD). It allows developers to write human-readable scenarios in plain text format, which are then executed by Behat. This helps in enhancing collaboration between developers, testers, and stakeholders, as everyone can understand the behavior of the application.

Use case 1: Initialize a new Behat project

Code:

behat --init

Motivation: Initializing a new Behat project is the first step to getting started with BDD. This command creates the necessary directories, configuration files, and example features to begin writing tests.

Explanation: The --init option tells Behat to initialize a new project. When this command is executed, Behat creates a “features” directory with an example feature file, a “bootstrap” directory with a “FeatureContext” file, and a “behat.yml” configuration file.

Example Output:

 + features/ - place your *.feature files here
 + features/bootstrap/ - place your context classes here
 + behat.yml - place your configuration settings here

Use case 2: Run all tests

Code:

behat

Motivation: Running all tests allows developers to ensure that the entire suite of tests passes without any issues. This is especially important when making changes to the application or before deploying it to production.

Explanation: Executing behat without any additional options tells Behat to run all tests defined in the project. Behat looks for all files with the “.feature” extension in the “features” directory and executes them accordingly.

Example Output:

10 scenarios (10 passed)
37 steps (37 passed)
0m0.562s

Use case 3: Run all tests from the specified suite

Code:

behat --suite=suite_name

Motivation: In complex projects, there might be multiple test suites targeting different parts of the application. Running tests from a specific suite allows developers to focus on specific areas and ensure their functionality.

Explanation: The --suite option tells Behat to run tests from a specific suite. The suite_name in the command should match the name of the suite defined in the “behat.yml” configuration file.

Example Output:

5 scenarios (5 passed)
20 steps (20 passed)
0m0.217s

Use case 4: Run tests with a specific output formatter

Code:

behat --format pretty|progress

Motivation: Behat provides a range of output formatters to display test results in different ways. Choosing a specific output formatter allows developers to customize the test result display based on their preferences or requirements.

Explanation: The --format option followed by the formatter name (either “pretty” or “progress”) tells Behat to use that specific output formatter. The “pretty” formatter provides a more human-readable output format, while the “progress” formatter shows a concise view of the test progress.

Example Output (with “–format pretty”):

10 scenarios (10 passed)
37 steps (37 passed)
0m0.562s

Example Output (with “–format progress”):

10/10 [============================] 100% 0m0.562s

Use case 5: Run tests and output results to a file

Code:

behat --out path/to/file

Motivation: Saving test results to a file allows developers to keep track of test execution history, generate reports, or share them with other team members or stakeholders.

Explanation: The --out option followed by the path to a file tells Behat to write the test results to that file. The path can be either absolute or relative to the current directory.

Example Output (in the specified file):

10 scenarios (10 passed)
37 steps (37 passed)
0m0.562s

Use case 6: Display a list of definitions in your test suites

Code:

behat --definitions

Motivation: Knowing the available step definitions in test suites allows developers to ensure that the desired steps are properly defined and can be used in feature files.

Explanation: The --definitions option tells Behat to display a list of available step definitions. These step definitions are defined in the context classes located in the “features/bootstrap” directory.

Example Output:

Available step definitions:
 - I open the homepage
 - I click on "Login" button
 - ...

Conclusion:

Behat is a powerful PHP framework for Behavior-Driven Development. By using the various options and commands provided by Behat, developers can initialize a new project, run tests, customize output format, save results to files, and view available step definitions. These capabilities make Behat a valuable tool for developing and testing applications using BDD principles.