diff --git a/features/behat-steps.feature b/features/behat-steps.feature
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+Feature: Test that WP-CLI Behat steps work as expected
+
+  This feature file contains functional tests for all the Behat steps
+  provided by the WP-CLI testing framework. It ensures that each Given,
+  When, and Then step definition works correctly.
+
+  The tests are organized by step type and functionality:
+  - Basic file and directory operations
+  - Command execution and output validation
+  - Variable management and replacement
+  - WordPress installation and configuration
+  - HTTP mocking and network operations
+  - Output format validation (JSON, CSV, YAML, tables)
+
+  Each scenario tests a specific step or combination of steps to verify
+  they produce the expected behavior.
+
+  Scenario: Test "Given an empty directory" step
+    Given an empty directory
+    Then the {RUN_DIR} directory should exist
+
+  Scenario: Test "Given a specific directory" steps
+    Given an empty directory
+    And an empty test-dir directory
+    Then the test-dir directory should exist
+
+    Given a non-existent test-dir directory
+    Then the test-dir directory should not exist
+
+  Scenario: Test "Given an empty cache" step
+    Given an empty cache
+    Then the {SUITE_CACHE_DIR} directory should exist
+
+  Scenario: Test "Given a file" step
+    Given an empty directory
+    And a test.txt file:
+      """
+      Hello World
+      """
+    Then the test.txt file should exist
+    And the test.txt file should contain:
+      """
+      Hello World
+      """
+
+  Scenario: Test "Given a cache file" step
+    Given an empty cache
+    And a test-cache.txt cache file:
+      """
+      Cached content
+      """
+    Then the {SUITE_CACHE_DIR}/test-cache.txt file should exist
+    And the {SUITE_CACHE_DIR}/test-cache.txt file should contain:
+      """
+      Cached content
+      """
+
+  Scenario: Test string replacement in file
+    Given an empty directory
+    And a config.txt file:
+      """
+      foo bar baz
+      """
+    And "foo" replaced with "hello" in the config.txt file
+    Then the config.txt file should contain:
+      """
+      hello bar baz
+      """
+
+  Scenario: Test "When I run" step with basic command
+    When I run `echo "test output"`
+    Then STDOUT should be:
+      """
+      test output
+      """
+    And STDERR should be empty
+    And the return code should be 0
+
+  Scenario: Test "When I try" step with failing command
+    When I try `false`
+    Then the return code should be 1
+
+  Scenario: Test "save STDOUT as" variable
+    When I run `echo "saved value"`
+    Then save STDOUT as {MY_VAR}
+
+    When I run `echo {MY_VAR}`
+    Then STDOUT should be:
+      """
+      saved value
+      """
+
+  Scenario: Test "save STDOUT with pattern" as variable
+    When I run `echo "Version 1.2.3 downloaded"`
+    Then save STDOUT 'Version ([\d\.]+)' as {VERSION}
+
+    When I run `echo {VERSION}`
+    Then STDOUT should be:
+      """
+      1.2.3
+      """
+
+  Scenario: Test "STDOUT should contain" step
+    When I run `echo "hello world"`
+    Then STDOUT should contain:
+      """
+      world
+      """
+
+  Scenario: Test "STDOUT should not contain" step
+    When I run `echo "hello world"`
+    Then STDOUT should not contain:
+      """
+      goodbye
+      """
+
+  Scenario: Test "STDOUT should be a number" step
+    When I run `echo 42`
+    Then STDOUT should be a number
+
+  Scenario: Test "STDOUT should not be a number" step
+    When I run `echo "not a number"`
+    Then STDOUT should not be a number
+
+  Scenario: Test "STDOUT should not be empty" step
+    When I run `echo "something"`
+    Then STDOUT should not be empty
+
+  Scenario: Test "STDERR should be empty" step
+    When I run `echo "test"`
+    Then STDERR should be empty
+
+  Scenario: Test "STDOUT should match" regex
+    When I run `echo "test-123"`
+    Then STDOUT should match /^test-\d+$/
+
+  Scenario: Test "STDOUT should not match" regex
+    When I run `echo "hello"`
+    Then STDOUT should not match /^\d+$/
+
+  Scenario: Test "the return code should be" step
+    When I run `true`
+    Then the return code should be 0
+
+    When I try `false`
+    Then the return code should be 1
+
+  Scenario: Test "the return code should not be" step
+    When I run `true`
+    Then the return code should not be 1
+
+  Scenario: Test "file should exist" step
+    Given an empty directory
+    And a myfile.txt file:
+      """
+      content
+      """
+    Then the myfile.txt file should exist
+
+  Scenario: Test "file should not exist" step
+    Given an empty directory
+    Then the missing.txt file should not exist
+
+  Scenario: Test "directory should exist" step
+    Given an empty directory
+    And an empty subdir directory
+    Then the subdir directory should exist
+
+  Scenario: Test "directory should not exist" step
+    Given an empty directory
+    Then the nonexistent directory should not exist
+
+  Scenario: Test "file should contain" step
+    Given an empty directory
+    And a content.txt file:
+      """
+      Line 1
+      Line 2
+      """
+    Then the content.txt file should contain:
+      """
+      Line 1
+      """
+
+  Scenario: Test "file should not contain" step
+    Given an empty directory
+    And a content.txt file:
+      """
+      Some content
+      """
+    Then the content.txt file should not contain:
+      """
+      Missing text
+      """
+
+  Scenario: Test "contents of file should match" regex
+    Given an empty directory
+    And a pattern.txt file:
+      """
+      Version: 1.2.3
+      """
+    Then the contents of the pattern.txt file should match /Version:\s+\d+\.\d+\.\d+/
+
+  Scenario: Test "contents of file should not match" regex
+    Given an empty directory
+    And a text.txt file:
+      """
+      No version here
+      """
+    Then the contents of the text.txt file should not match /Version:\s+\d+/
+
+  Scenario: Test "directory should contain" files
+    Given an empty directory
+    And a file1.txt file:
+      """
+      content1
+      """
+    And a file2.txt file:
+      """
+      content2
+      """
+    Then the {RUN_DIR} directory should contain:
+      """
+      file1.txt
+      """
+    And the {RUN_DIR} directory should contain:
+      """
+      file2.txt
+      """
+
+  Scenario: Test "I run the previous command again" step
+    When I run `echo "test"`
+    Then STDOUT should contain:
+      """
+      test
+      """
+
+    When I run the previous command again
+    Then STDOUT should contain:
+      """
+      test
+      """
+
+  Scenario: Test variable replacement in commands
+    When I run `echo "myvalue"`
+    Then save STDOUT as {TEST_VAR}
+
+    When I run `echo "Value is: {TEST_VAR}"`
+    Then STDOUT should contain:
+      """
+      myvalue
+      """
+
+  Scenario: Test STDOUT strictly be
+    When I run `echo "exact"`
+    Then STDOUT should strictly be:
+      """
+      exact
+      """
+
+  Scenario: Test file strictly contain
+    Given an empty directory
+    And a strict.txt file:
+      """
+      exact content
+      """
+    Then the strict.txt file should strictly contain:
+      """
+      exact content
+      """
+
+  @require-wp
+  Scenario: Test WP installation steps
+    Given a WP installation
+    When I run `wp core version`
+    Then STDOUT should not be empty
+    And the return code should be 0
+
+  @require-wp
+  Scenario: Test WP files and wp-config.php steps
+    Given an empty directory
+    And WP files
+    Then the wp-settings.php file should exist
+
+    Given wp-config.php
+    Then the wp-config.php file should exist
+    And the wp-config.php file should contain:
+      """
+      DB_NAME
+      """
+
+  @require-wp
+  Scenario: Test WP installation in subdirectory
+    Given a WP installation in 'subdir'
+    When I run `wp core version` from 'subdir'
+    Then STDOUT should not be empty
+    And the return code should be 0
+
+
+
+  @require-wp
+  Scenario: Test version string comparison
+    Given a WP installation
+    When I run `wp core version`
+    Then STDOUT should be a version string >= 4.0
+
+  Scenario: Test STDOUT as table containing rows
+    When I run `printf "name\tversion\nfoo\t1.0\nbar\t2.0"`
+    Then STDOUT should be a table containing rows:
+      | name | version |
+      | foo  | 1.0     |
+
+  Scenario: Test JSON output
+    When I run `echo '{"name":"test","value":"example.com"}'`
+    Then STDOUT should be JSON containing:
+      """
+      {"name":"test"}
+      """
+
+  Scenario: Test CSV output
+    When I run `printf "user_login,user_email\nadmin,admin@example.com"`
+    Then STDOUT should contain:
+      """
+      user_login
+      """
+
+  Scenario: Test YAML output
+    When I run `printf "name: test\nversion: 1.0"`
+    Then STDOUT should be YAML containing:
+      """
+      name: test
+      """
+
+  @require-wp
+  Scenario: Test save file as variable
+    Given a WP installation
+    And a composer.json file:
+      """
+      {"name": "test"}
+      """
+    And save the {RUN_DIR}/composer.json file as {COMPOSER}
+    When I run `echo '{COMPOSER}'`
+    Then STDOUT should contain:
+      """
+      test
+      """
+
+  Scenario: Test HTTP request mocking
+    Given that HTTP requests to https://example.com/test will respond with:
+      """
+      HTTP/1.1 200
+      Content-Type: text/plain
+
+      Mock response
+      """
+    Then the wp-cli.yml file should exist
+    And the mock-requests.php file should exist
+
+  @require-wp
+  Scenario: Test background process launch
+    Given a WP installation
+    When I launch in the background `wp eval 'sleep(2); echo "done";'`
+    # Background process should not block, continuing immediately
+
+  @require-wp
+  Scenario: Test custom wp-content directory
+    Given a WP installation
+    And a custom wp-content directory
+    Then the my-content directory should exist
+    And the my-plugins directory should exist
+    And the my-mu-plugins directory should exist
+    And the wp-config.php file should contain:
+      """
+      WP_CONTENT_DIR
+      """
+
+  @require-wp
+  Scenario: Test WP multisite subdirectory installation
+    Given a WP multisite subdirectory installation
+    When I run `wp core is-installed --network`
+    Then the return code should be 0
+
+  @require-wp
+  Scenario: Test WP multisite subdomain installation
+    Given a WP multisite subdomain installation
+    When I run `wp core is-installed --network`
+    Then the return code should be 0
+
+  @require-wp
+  Scenario: Test misconfigured WP_CONTENT_DIR
+    Given a WP installation
+    And a misconfigured WP_CONTENT_DIR constant directory
+    Then the wp-config.php file should contain:
+      """
+      define( 'WP_CONTENT_DIR', '' );
+      """
+
+  @require-download
+  Scenario: Test download step
+    Given an empty cache
+    And download:
+      | path                       | url                                    |
+      | {SUITE_CACHE_DIR}/test.txt | https://www.iana.org/robots.txt        |
+    Then the {SUITE_CACHE_DIR}/test.txt file should exist
+
+  @require-wp @require-composer
+  Scenario: Test WP installation with Composer
+    Given a WP installation with Composer
+    Then the composer.json file should exist
+    And the vendor directory should exist
+    When I run `wp core version`
+    Then STDOUT should not be empty
+
+  @require-wp @require-composer
+  Scenario: Test WP installation with Composer and custom vendor directory
+    Given a WP installation with Composer and a custom vendor directory 'custom-vendor'
+    Then the composer.json file should exist
+    And the custom-vendor directory should exist
+
+  @require-wp @require-composer
+  Scenario: Test dependency on current wp-cli
+    Given a WP installation with Composer
+    And a dependency on current wp-cli
+    Then the composer.json file should contain:
+      """
+      wp-cli/wp-cli
+      """
+
+
+
+  Scenario: Test STDOUT should be empty
+    When I run `echo -n ""`
+    Then STDOUT should be empty
+
+  Scenario: Test running command from subdirectory
+    Given an empty directory
+    And an empty testdir directory
+    When I run `pwd` from 'testdir'
+    Then STDOUT should contain:
+      """
+      testdir
+      """
+
+  Scenario: Test STDOUT strictly contain
+    When I run `echo "exact"`
+    Then STDOUT should strictly contain:
+      """
+      exact
+      """
+
+  Scenario: Test STDERR output
+    When I try `bash -c 'echo "error message" >&2'`
+    Then STDERR should contain:
+      """
+      error message
+      """
+    And STDERR should not be empty
+
+  Scenario: Test file path with nested directory
+    Given an empty directory
+    And a nested/path/file.txt file:
+      """
+      content
+      """
+    Then the nested/path/file.txt file should contain:
+      """
+      content
+      """
+
+  Scenario: Test multiple files in directory
+    Given an empty directory
+    And a file-a.txt file:
+      """
+      A
+      """
+    And a file-b.txt file:
+      """
+      B
+      """
+    And a file-c.txt file:
+      """
+      C
+      """
+    Then the {RUN_DIR} directory should contain:
+      """
+      file-a.txt
+      """
+    And the {RUN_DIR} directory should contain:
+      """
+      file-b.txt
+      """
+    And the {RUN_DIR} directory should contain:
+      """
+      file-c.txt
+      """
+
+  Scenario: Test special characters in file content
+    Given an empty directory
+    And a special.txt file:
+      """
+      Line with "quotes"
+      Line with 'apostrophes'
+      Line with $variable
+      """
+    Then the special.txt file should contain:
+      """
+      quotes
+      """
+
+  Scenario: Test version comparison operators
+    When I run `echo "5.6.2"`
+    Then STDOUT should be a version string > 5.6.1
+    And STDOUT should be a version string >= 5.6.2
+    And STDOUT should be a version string < 5.6.3
+    And STDOUT should be a version string <= 5.6.2
+    And STDOUT should be a version string == 5.6.2
+    And STDOUT should be a version string != 5.6.3
+
+  @require-wp
+  Scenario: Test JSON array containing
+    Given a WP installation
+    When I run `wp eval 'echo json_encode(["apple", "banana", "cherry"]);'`
+    Then STDOUT should be a JSON array containing:
+      """
+      ["apple", "banana"]
+      """
+
+  @require-wp
+  Scenario: Test email sending detection
+    Given a WP installation
+    And a send-email.php file:
+      """
+      <?php
+      wp_mail('test@example.com', 'Test', 'Body');
+      """
+    When I run `wp eval-file send-email.php`
+    Then an email should be sent
+
+  Scenario: Test STDOUT end with table
+    When I run `printf "Some output\nuser_login\nadmin\nuser2"`
+    Then STDOUT should end with a table containing rows:
+      | user_login |
+      | admin      |
+
+  Scenario: Test combining multiple string replacements
+    Given an empty directory
+    And a template.txt file:
+      """
+      Hello FIRST_NAME LAST_NAME
+      """
+    And "FIRST_NAME" replaced with "John" in the template.txt file
+    And "LAST_NAME" replaced with "Doe" in the template.txt file
+    Then the template.txt file should contain:
+      """
+      Hello John Doe
+      """
+
+  Scenario: Test nested directory creation
+    Given an empty directory
+    And a deep/nested/path/file.txt file:
+      """
+      Deep content
+      """
+    Then the deep/nested/path/file.txt file should exist
+
+  Scenario: Test absolute vs relative paths
+    Given an empty directory
+    And a relative.txt file:
+      """
+      Relative
+      """
+    Then the relative.txt file should exist
+    And the {RUN_DIR}/relative.txt file should exist
+
+
+
+
+
+  Scenario: Test variable naming conventions
+    When I run `echo "value1"`
+    Then save STDOUT as {VAR_NAME}
+
+    When I run `echo {VAR_NAME}`
+    Then STDOUT should be:
+      """
+      value1
+      """
+
+  Scenario: Test variable with underscore prefix
+    When I run `echo "value2"`
+    Then save STDOUT as {_UNDERSCORE_VAR}
+
+    When I run `echo {_UNDERSCORE_VAR}`
+    Then STDOUT should contain:
+      """
+      value2
+      """
+
+  Scenario: Test variable with numbers
+    When I run `echo "value3"`
+    Then save STDOUT as {VAR123}
+
+    When I run `echo {VAR123}`
+    Then STDOUT should contain:
+      """
+      value3
+      """
+
+  Scenario: Test built-in variables
+    Given an empty directory
+    When I run `pwd`
+    Then STDOUT should contain:
+      """
+      {RUN_DIR}
+      """
+
+  Scenario: Test CACHE_DIR variable
+    Given an empty cache
+    When I run `echo {SUITE_CACHE_DIR}`
+    Then STDOUT should not be empty
+
+  Scenario: Test multiline STDOUT capture
+    When I run `printf "line1\nline2\nline3"`
+    Then STDOUT should contain:
+      """
+      line1
+      """
+    And STDOUT should contain:
+      """
+      line2
+      """
+    And STDOUT should contain:
+      """
+      line3
+      """
+
+  Scenario: Test STDERR capture
+    When I try `bash -c 'echo "stdout"; echo "stderr" >&2'`
+    Then STDOUT should contain:
+      """
+      stdout
+      """
+    And STDERR should contain:
+      """
+      stderr
+      """
+
+  Scenario: Test file with multiline content
+    Given an empty directory
+    And a multiline.txt file:
+      """
+      First line
+      Second line
+      Third line
+      """
+    Then the multiline.txt file should contain:
+      """
+      First line
+      """
+    And the multiline.txt file should contain:
+      """
+      Second line
+      """
+    And the multiline.txt file should contain:
+      """
+      Third line
+      """
+
+  Scenario: Test return code not be assertion
+    When I run `true`
+    Then the return code should not be 1
+    And the return code should not be 2
+
+  Scenario: Test CSV containing with headers
+    When I run `printf "user_login,user_email\nadmin,admin@example.com\nuser2,user2@example.com"`
+    Then STDOUT should be CSV containing:
+      | user_login | user_email        |
+      | admin      | admin@example.com |