Add comprehensive Behat testing guide to handbook

[Copilot]

Created comprehensive Behat tests documentation guide:

• Create new guide file guides/behat-tests.md with comprehensive Behat testing documentation
  • Introduction section: What are Behat tests, why they matter, getting started
  • Writing your first test: Basic structure, common steps, running tests
  • Advanced usage section: Effective tests, variables, structured output, error testing, custom steps
  • Best practices: Do's and don'ts for writing maintainable tests
  • Scaffolding and troubleshooting sections
  • Additional resources and examples
• Update guides.md to include link to new Behat tests guide
• Update index.md to include link to new Behat tests guide
• Update bin/handbook-manifest.json to register the new guide
• Update contributions/pull-requests.md to link to the new comprehensive guide
• Update guides/external-resources.md to add the Delicious Brains article
• Address review feedback: Add SQLite option and improve database setup documentation
  • Recommend SQLite as the easiest option (no database setup required)
  • Remove manual MySQL database creation steps
  • Emphasize using composer prepare-tests for MySQL setup
  • Update troubleshooting section to mention SQLite first
• Document automatic SQLite fallback behavior
  • Note that composer behat automatically detects database availability
  • Falls back to SQLite if no running database is found
  • Makes getting started even easier with zero configuration

The guide now clearly explains that contributors can simply run composer behat without any database setup, as it will automatically use SQLite when needed.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Create a dedicated doc for how to write Behat tests</issue_title>
<issue_description>WP-CLI integration test documentation exists in two places:

• https://make.wordpress.org/cli/handbook/pull-requests/#running-and-writing-tests
• https://github.com/wp-cli/scaffold-package-command#wp-scaffold-package-tests

It would be more user-friendly to have an uberdoc for Behat tests. We could have two sections:

1. Introduction - Getting started, and writing your first test
2. Advanced usage - Now that you've written a test, here's how you write steps, etc.

Once this document exists, we can have both existing places link directly to it.

Related https://deliciousbrains.com/writing-functional-tests-wp-cli-packages/</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Create a dedicated doc for how to write Behat tests #3

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[Copilot]

Pull request overview

This PR creates a comprehensive Behat testing guide for WP-CLI contributors, consolidating documentation that was previously scattered across multiple locations. The new guide provides clear, structured documentation for writing functional tests, including SQLite as a recommended easy setup option.

Changes:

• Added new comprehensive Behat testing guide at guides/behat-tests.md covering introduction, writing tests, advanced usage, best practices, and troubleshooting
• Updated handbook navigation files (index.md, guides.md) and manifest to include the new guide
• Modified contributions/pull-requests.md to reference the comprehensive guide instead of duplicating content
• Added the Delicious Brains article to external resources

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
guides/behat-tests.md	New comprehensive guide covering all aspects of Behat testing for WP-CLI, including setup with SQLite/MySQL, writing tests, advanced features, and troubleshooting
index.md	Added link to new Behat testing guide in the guides section
guides.md	Added link to new Behat testing guide
contributions/pull-requests.md	Streamlined functional tests section to reference the comprehensive guide, removing duplicated content
guides/external-resources.md	Added Delicious Brains article on writing functional tests
bin/handbook-manifest.json	Registered the new behat-tests guide page

Comments suppressed due to low confidence (1)

contributions/pull-requests.md:138

• The code block is tagged with 'yml' language identifier, but Behat feature files use Gherkin syntax, not YAML. While the syntax highlighting might work, it would be more accurate to use 'gherkin' or 'cucumber' as the language identifier for better semantic accuracy.

```yml
Feature: Manage WordPress options

  Scenario: Read an individual option
    Given a WP install

	When I run `wp option get home`
	Then STDOUT should be:
      """
	  https://example.com
	  """

</details>



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[Copilot]

The statement that feature files are "YAML-formatted" is incorrect. Behat feature files use Gherkin syntax, not YAML. While both use indentation and have a structured format, Gherkin is its own domain-specific language. This should be corrected to avoid confusion.

Suggested change

	Every WP-CLI repository with commands has a `features/` directory containing one or more YAML-formatted `*.feature` files.
	Every WP-CLI repository with commands has a `features/` directory containing one or more `*.feature` files written in Gherkin syntax.

[Copilot]

There is trailing whitespace at the end of this line that should be removed.

Suggested change

	* [Delicious Brains: Writing Functional Tests for WP-CLI Packages](https://deliciousbrains.com/writing-functional-tests-wp-cli-packages/)
	* [Delicious Brains: Writing Functional Tests for WP-CLI Packages](https://deliciousbrains.com/writing-functional-tests-wp-cli-packages/)

[Copilot]

This section only mentions MySQL/MariaDB database setup, but the new comprehensive guide recommends SQLite as the easiest option. Consider adding a note here that SQLite can be used as an alternative by setting WP_CLI_TEST_DBTYPE=sqlite, which requires no database setup. This would be consistent with the new guide and provide a simpler path for contributors.