[PATCH 10/11] doc: improve unit test guide readability

Stephen Hemminger
2026-01-14T22:57:07Z

Improve the unit test documentation
- Converting passive voice to active voice
- Using imperative mood for instructions
- Simplifying wordy constructions
- Removing unnecessary include statements from code example
- Fixing minor grammar and punctuation issues

No technical content changes.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
doc/guides/contributing/unit_test.rst | 113 ++++++++++++--------------
1 file changed, 52 insertions(+), 61 deletions(-)

diff --git a/doc/guides/contributing/unit_test.rst b/doc/guides/contributing/unit_test.rst
index c0f0d2988f..5b22393e6f 100644
--- a/doc/guides/contributing/unit_test.rst
+++ b/doc/guides/contributing/unit_test.rst
@@ -9,7 +9,7 @@ tests to the in-tree DPDK test suites.

The DPDK test suite model is loosely based on the xUnit model,
where tests are grouped into test suites, and suites are run by runners.
-For a basic overview, see the basic Wikipedia article on `xUnit
+For a basic overview, see the Wikipedia article on `xUnit
<https://en.wikipedia.org/wiki/XUnit>`_.

@@ -18,13 +18,13 @@ Background

The in-tree testing infrastructure for DPDK consists of
multiple applications and support tools.
-The primary tools are the `dpdk-test` application,
+The primary tools are the `dpdk-test` application
and the ``meson test`` infrastructure.
-These two are the primary ways through which
-a user will interact with the DPDK testing infrastructure.
+These two are the primary ways
+users interact with the DPDK testing infrastructure.

-There exists a bit of confusion with the test suite and test case separation
-with respect to `dpdk-test` and ``meson test``.
+Some confusion exists regarding test suite and test case separation
+between `dpdk-test` and ``meson test``.
Both have a concept of test suite and test case.
In both, the concept is similar.
A test suite is a group of test cases,
@@ -36,14 +36,14 @@ to denote a Meson test suite / case.
Running a test
--------------

-DPDK tests are run via the main test runner, the `dpdk-test` app.
+DPDK tests run via the main test runner, the `dpdk-test` app.
The `dpdk-test` app is a command-line interface that facilitates
running various tests or test suites.

There are three modes of operation.
-The first mode is as an interactive command shell
+The first mode is an interactive command shell
that allows launching specific test suites.
-This is the default operating mode of `dpdk-test` and can be done by::
+This is the default operating mode of `dpdk-test` and can be invoked by::

$ ./build/app/test/dpdk-test --dpdk-options-here
EAL: Detected 4 lcore(s)
@@ -58,12 +58,12 @@ This is the default operating mode of `dpdk-test` and can be done by::
APP: HPET is not enabled, using TSC as default timer
RTE>>

-At the prompt, simply type the name of the test suite you wish to run
+At the prompt, type the name of the test suite you wish to run
and it will execute.

-The second form is useful for a scripting environment,
+The second form is useful for a scripting environment
and is used by the DPDK Meson build system.
-This mode is invoked by
+Invoke this mode by
assigning a specific test suite name to the environment variable ``DPDK_TEST``
before invoking the `dpdk-test` command, such as::

@@ -84,7 +84,7 @@ before invoking the `dpdk-test` command, such as::
RTE>>$

The above shows running a specific test case.
-On success, the return code will be '0',
+On success, the return code will be '0';
otherwise it will be set to some error value (such as '255', or a negative value).

The third form is an alternative
@@ -110,20 +110,20 @@ The unit test app can accept test suite names via command line arguments::
The primary benefit here is specifying multiple test names,
which is not possible with the ``DPDK_TEST`` environment variable.

-Additionally, it is possible to specify additional test parameters
+Additionally, specify additional test parameters
via the ``DPDK_TEST_PARAMS`` argument,
in case some tests need additional configuration.
-This isn't currently used in the Meson test suites.
+This is not currently used in the Meson test suites.

Running test cases via Meson
----------------------------

-In order to allow developers to quickly execute all the standard internal tests
+To allow developers to quickly execute all the standard internal tests
without needing to remember or look up each test suite name,
the build system includes a standard way of executing the Meson test suites.
After building via ``ninja``, the ``meson test`` command
-with no arguments will execute the Meson test suites.
+with no arguments executes the Meson test suites.

There are a number of pre-configured Meson test suites.
The first is the **fast** test suite, which is the largest group of test cases.
@@ -133,9 +133,9 @@ These test suites can take longer to run and do performance evaluations.
The third is the **driver** test suite,
which is mostly for special hardware related testing (such as `cryptodev`).
The fourth, and currently the last, suite is the **debug** suite.
-These tests mostly are used to dump system information.
+These tests mostly dump system information.

-The Meson test suites can be selected by adding the ``--suite`` option
+Select the Meson test suites by adding the ``--suite`` option
to the ``meson test`` command.
Ex: ``meson test --suite fast-tests``::

@@ -159,19 +159,19 @@ via the command line by adding the test names as an argument::
1/1 DPDK:fast-tests / version_autotest OK 0.17s
...

-Note that these test cases must be known to Meson
+Note that Meson must know these test cases
for the ``meson test`` command to run them.
-Simply adding a new test to the `dpdk-test` application isn't enough.
+Simply adding a new test to the `dpdk-test` application is not enough.
See the section `Adding a suite or test case to Meson`_ for more details.

Adding tests to dpdk-test application
-------------------------------------

-Unit tests should be added to the system
-whenever we introduce new functionality to DPDK,
-as well as whenever a bug is resolved.
-This helps the DPDK project to catch regressions as they are introduced.
+Add unit tests to the system
+whenever introducing new functionality to DPDK
+or resolving a bug.
+This helps the DPDK project catch regressions as they occur.

The DPDK test application supports two layers of tests:
#. *test cases* which are individual tests
@@ -185,12 +185,12 @@ There are two important functions for interacting with the test harness:
``REGISTER_<MESON_SUITE>_TEST(command_name, function_to_execute)``
Registers a test command with the name `command_name`
and which runs the function `function_to_execute` when `command_name` is invoked.
- The test is automatically added to the Meson test suite `<MESON_SUITE>` by this macro.
- Examples would be ``REGISTER_DRIVER_TEST``, or ``REGISTER_PERF_TEST``.
+ This macro automatically adds the test to the Meson test suite `<MESON_SUITE>`.
+ Examples: ``REGISTER_DRIVER_TEST``, or ``REGISTER_PERF_TEST``.
**NOTE:** The ``REGISTER_FAST_TEST`` macro is slightly different,
in that it takes two additional parameters,
- specifying whether the test can be run using ``--no-huge``,
- and whether the test can be run using Address Sanitization (ASAN)
+ specifying whether the test can run using ``--no-huge``,
+ and whether the test can run using Address Sanitization (ASAN).

``unit_test_suite_runner(struct unit_test_suite *)``
Returns a runner for a full test suite object,
@@ -203,28 +203,19 @@ that runs at the beginning and end of the test suite execution.
Each unit test has a similar function for test case setup and tear down.

Each test suite may use a nested list of sub-testsuites,
-which are iterated by the ``unit_test_suite_runner``.
+which the ``unit_test_suite_runner`` iterates.
This support allows for better granularity when designing test suites.
-The sub-testsuites list can also be used in parallel with the vector of test cases,
-in this case the test cases will be run,
-and then each sub-testsuite is executed.
+The sub-testsuites list can also be used in parallel with the vector of test cases;
+in this case, the test cases run first,
+then each sub-testsuite executes.
To see an example of a test suite using sub-testsuites,
see *app/test/test_cryptodev.c*.

-Test cases are added to the ``.unit_test_cases`` element
-of the appropriate unit test suite structure.
-An example of both a test suite and a case:
+Example of a test suite with a single test case:

.. code-block:: c
:linenos:

- #include <time.h>
-
- #include <rte_common.h>
- #include <rte_cycles.h>
- #include <rte_hexdump.h>
- #include <rte_random.h>
-
#include "test.h"

static int testsuite_setup(void) { return TEST_SUCCESS; }
@@ -256,7 +247,7 @@ An example of both a test suite and a case:
The above code block is a small example
that can be used to create a complete test suite with test case.

-Sub-testsuites can be added to the ``.unit_test_suites`` element
+Add sub-testsuites to the ``.unit_test_suites`` element
of the unit test suite structure, for example:

.. code-block:: c
@@ -335,13 +326,13 @@ The first way to indicate a generic error is
by returning a test result failure, using the ``TEST_FAILED`` error code.
This is the most basic way of indicating that an error
has occurred in a test routine.
-It isn't very informative to the user, so it should really be used in cases
+It is not very informative to the user, so use it in cases
where the test has catastrophically failed.

The preferred method of indicating an error is
via the ``RTE_TEST_ASSERT`` family of macros,
-which will immediately return ``TEST_FAILED`` error condition,
-but will also log details about the failure.
+which immediately return ``TEST_FAILED`` error condition,
+but also log details about the failure.
The basic form is:

.. code-block:: c
@@ -350,16 +341,16 @@ The basic form is:

In the above macro, *cond* is the condition to evaluate to **true**.
Any generic condition can go here.
-The *msg* parameter will be a message to display if *cond* evaluates to **false**.
+The *msg* parameter is a message to display if *cond* evaluates to **false**.
Some specialized macros already exist.
See `lib/librte_eal/include/rte_test.h` for a list of defined test assertions.

Sometimes it is important to indicate that a test needs to be skipped,
-either because the environment isn't able to support running the test,
-or because some requisite functionality isn't available.
+either because the environment cannot support running the test,
+or because some requisite functionality is unavailable.
The test suite supports returning a result of ``TEST_SKIPPED``
during test case setup, or during test case execution
-to indicate that the preconditions of the test aren't available.
+to indicate that the preconditions of the test are not available.
Example::

$ meson test -C build --suite fast-tests
@@ -386,10 +377,10 @@ Example::
$ meson test -C build --suite fast-tests
$ ninja coverage-html -C build

-The above will generate an HTML report
+The above generates an HTML report
in the `build/meson-logs/coveragereport/` directory
that can be explored for detailed code covered information.
-This can be used to assist in test development.
+Use this to assist in test development.

Adding a suite or test case to Meson
@@ -400,10 +391,10 @@ to register the test in dpdk-test, as described above.
For example,
defining the test command using ``REGISTER_PERF_TEST`` automatically
adds the test to the perf-test meson suite.
-Once added, the new test will be run
+Once added, the new test runs
as part of the appropriate class (fast, perf, driver, etc.).

-A user or developer can confirm that a test is known to Meson
+Confirm that a test is known to Meson
by using the ``--list`` option::

$ meson test -C build --list
@@ -411,12 +402,12 @@ by using the ``--list`` option::
DPDK:fast-tests / bitops_autotest
...

-Some of these test suites are run during continuous integration tests,
+Some of these test suites run during continuous integration tests,
making regression checking automatic for new patches submitted to the project.

.. note::

- The use of the old ``REGISTER_TEST_COMMAND`` macro
+ The old ``REGISTER_TEST_COMMAND`` macro
to add a command without adding it to a meson test suite is deprecated.
All new tests must be added to a test suite
using the appropriate ``REGISTER_<SUITE>_TEST`` macro.
@@ -424,8 +415,8 @@ making regression checking automatic for new patches submitted to the project.
Running cryptodev tests
-----------------------

-When running cryptodev tests, the user must create any required virtual device
-via EAL arguments, as this is not automatically done by the test::
+When running cryptodev tests, create any required virtual device
+via EAL arguments, as this is not done automatically by the test::

$ ./build/app/test/dpdk-test --vdev crypto_aesni_mb
$ meson test -C build --suite driver-tests \
@@ -433,6 +424,6 @@ via EAL arguments, as this is not automatically done by the test::

.. note::

- The ``cryptodev_scheduler_autotest`` is the only exception to this.
- This vdev will be created automatically by the test app,
+ The ``cryptodev_scheduler_autotest`` is the only exception.
+ This vdev is created automatically by the test app,
as it requires a more complex setup than other vdevs.
--
2.51.0