[PATCH v2] Documentation: kunit: rewrite writing first test instructions

From: Bagas Sanjaya
Date: Thu Sep 29 2022 - 09:26:56 EST


The wordings of step-by-step instructions on writing the first Kunit test
are instructing readers to write codes without knowing what these are about.
Rewrite these instructions to include the purpose of written code.

While at it, align the code blocks of these contents.

Signed-off-by: Bagas Sanjaya <bagasdotme@xxxxxxxxx>
---
Changes since v1 [1]:

- Fix jumped list numbering on writing the feature

This patch is based on Khalid's full path to .kunitconfig patch [2].

[1]: https://lore.kernel.org/linux-doc/20220929125458.52979-1-bagasdotme@xxxxxxxxx/
[2]: https://lore.kernel.org/linux-doc/20220929085332.4155-1-khalid.masum.92@xxxxxxxxx/

Documentation/dev-tools/kunit/start.rst | 40 ++++++++++++++-----------
1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/Documentation/dev-tools/kunit/start.rst b/Documentation/dev-tools/kunit/start.rst
index 7999874dc4ddb3..c0a5adf6d8d665 100644
--- a/Documentation/dev-tools/kunit/start.rst
+++ b/Documentation/dev-tools/kunit/start.rst
@@ -131,17 +131,19 @@ are built-in. Otherwise the module will need to be loaded.

Writing Your First Test
=======================
-In your kernel repository, let's add some code that we can test.
+In your kernel repository, let's add some code that we can test. For this
+purpose, we are going to add simple addition driver.

-1. Create a file ``drivers/misc/example.h``, which includes:
+1. Write the feature that will be tested. First, write the declaration
+ for ``misc_example_add()`` in ``drivers/misc/example.h``:

-.. code-block:: c
+ .. code-block:: c

int misc_example_add(int left, int right);

-2. Create a file ``drivers/misc/example.c``, which includes:
+ Then implement the function in ``drivers/misc/example.c``:

-.. code-block:: c
+ .. code-block:: c

#include <linux/errno.h>

@@ -152,24 +154,25 @@ In your kernel repository, let's add some code that we can test.
return left + right;
}

-3. Add the following lines to ``drivers/misc/Kconfig``:
+2. Add Kconfig menu entry for the feature to ``drivers/misc/Kconfig``:

-.. code-block:: kconfig
+ .. code-block:: kconfig

config MISC_EXAMPLE
bool "My example"

-4. Add the following lines to ``drivers/misc/Makefile``:
+3. Add the kbuild goal that will build the feature to
+ ``drivers/misc/Makefile``:

-.. code-block:: make
+ .. code-block:: make

obj-$(CONFIG_MISC_EXAMPLE) += example.o

Now we are ready to write the test cases.

-1. Add the below test case in ``drivers/misc/example_test.c``:
+1. Write the test in ``drivers/misc/example_test.c``:

-.. code-block:: c
+ .. code-block:: c

#include <kunit/test.h>
#include "example.h"
@@ -202,31 +205,32 @@ Now we are ready to write the test cases.
};
kunit_test_suite(misc_example_test_suite);

-2. Add the following lines to ``drivers/misc/Kconfig``:
+2. Add following Kconfig entry for the test to ``drivers/misc/Kconfig``:

-.. code-block:: kconfig
+ .. code-block:: kconfig

config MISC_EXAMPLE_TEST
tristate "Test for my example" if !KUNIT_ALL_TESTS
depends on MISC_EXAMPLE && KUNIT=y
default KUNIT_ALL_TESTS

-3. Add the following lines to ``drivers/misc/Makefile``:
+3. Add kbuild goal of the test to ``drivers/misc/Makefile``:

-.. code-block:: make
+ .. code-block:: make

obj-$(CONFIG_MISC_EXAMPLE_TEST) += example_test.o

-4. Add following configuration fragments to ``.kunit/.kunitconfig``:
+4. Add following configuration fragments for the test to
+ ``.kunit/.kunitconfig``:

-.. code-block:: none
+ .. code-block:: none

CONFIG_MISC_EXAMPLE=y
CONFIG_MISC_EXAMPLE_TEST=y

5. Run the test:

-.. code-block:: bash
+ .. code-block:: bash

./tools/testing/kunit/kunit.py run

--
An old man doll... just what I always wanted! - Clara