doc/dev/developer_guide/testing_integration_tests: Document the random selection...

Document about the '$' operator which is the random selection operator.

Fixes: https://tracker.ceph.com/issues/55198
Signed-off-by: Milind Changire <mchangir@redhat.com>

diff --git a/doc/dev/developer_guide/testing_integration_tests/tests-integration-testing-teuthology-intro.rst b/doc/dev/developer_guide/testing_integration_tests/tests-integration-testing-teuthology-intro.rst
index 3cbe51241cc984d1557aa16d3c98f5d7448b00d1..7c6916138dd35957df0a8104dae1d0ba3795f0d2 100644 (file)
--- a/doc/dev/developer_guide/testing_integration_tests/tests-integration-testing-teuthology-intro.rst
+++ b/doc/dev/developer_guide/testing_integration_tests/tests-integration-testing-teuthology-intro.rst
@@ -308,16 +308,16 @@ directory tree within the ``suites/`` subdirectory of the `ceph/qa sub-directory
 The set of all tests defined by a given subdirectory of ``suites/`` is
 called an "integration test suite", or a "teuthology suite".
 
-Combination of yaml facets is controlled by special files (``%`` and
-``+``) that are placed within the directory tree and can be thought of as
-operators.  The ``%`` file is the "convolution" operator and ``+``
-signifies concatenation.
+Combination of YAML facets is controlled by special files (``%``, ``+`` and ``$``)
+that are placed within the directory tree and can be thought of as
+operators.  The ``%`` file is the "convolution" operator, ``+`` signifies
+concatenation and ``$`` is the "random selection" operator.
 
-Convolution operator
-^^^^^^^^^^^^^^^^^^^^
+Convolution operator - ``%``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 The convolution operator, implemented as a (typically empty) file called ``%``,
-tells teuthology to construct a test matrix from yaml facets found in
+tells teuthology to construct a test matrix from YAML facets found in
 subdirectories below the directory containing the operator.
 
 For example, the `ceph-deploy suite
@@ -412,8 +412,8 @@ tests will still preserve the correct numerator (subset of subsets).
 You can disable nested subsets using the ``--no-nested-subset`` argument to
 ``teuthology-suite``.
 
-Concatenation operator
-^^^^^^^^^^^^^^^^^^^^^^
+Concatenation operator - ``+``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 For even greater flexibility in sharing yaml files between suites, the
 special file plus (``+``) can be used to concatenate files within a
@@ -552,6 +552,15 @@ rest of the cluster (``5-finish-upgrade.yaml``).
 The last stage is requiring the updated release (``ceph require-osd-release quincy``,
 ``ceph osd set-require-min-compat-client quincy``) and running the ``final-workload``.
 
+Random Selection Operator - ``$``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The presence of a file named ``$`` provides a hint to teuthology to randomly
+include one of the YAML fragments in the test. Such a scenario is typically
+seen when we need to choose one of the flavors of the features/options to be
+tested randomly.
+
+
 Position Independent Linking
 ----------------------------