[PATCH v3 1/1] Documentation: dev-tools: clarify KTAP specification wording

[frowand . list]

From: Frank Rowand <frank.rowand@xxxxxxxx>

Add the spec version to the title line.

Explain likely source of "Unknown lines".

"Unknown lines" in nested tests are optionally indented.

Add "Unknown lines" items to differences between TAP & KTAP list

Reviewed-by: Tim Bird <Tim.Bird@xxxxxxxx>
Reviewed-by: David Gow <davidgow@xxxxxxxxxx>
Signed-off-by: Frank Rowand <frank.rowand@xxxxxxxx>
---

Changes since version 2
  - Add missing quote after word: incorrect
  - Add Reviewed-by tags

Changes since version 1
  - Explain likely source of "Unknown lines"
  - "Unknown line" in nested tests are optionally indented
  - Add "Unknown lines" items to differences between TAP & KTAP list

 Documentation/dev-tools/ktap.rst | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/Documentation/dev-tools/ktap.rst b/Documentation/dev-tools/ktap.rst
index 878530cb9c27..dfb3f10a8b2d 100644
--- a/Documentation/dev-tools/ktap.rst
+++ b/Documentation/dev-tools/ktap.rst
@@ -1,8 +1,8 @@
 .. SPDX-License-Identifier: GPL-2.0
 
-========================================
-The Kernel Test Anything Protocol (KTAP)
-========================================
+===================================================
+The Kernel Test Anything Protocol (KTAP), version 1
+===================================================
 
 TAP, or the Test Anything Protocol is a format for specifying test results used
 by a number of projects. It's website and specification are found at this `link
@@ -174,6 +174,13 @@ There may be lines within KTAP output that do not follow the format of one of
 the four formats for lines described above. This is allowed, however, they will
 not influence the status of the tests.
 
+This is an important difference from TAP.  Kernel tests may print messages
+to the system console or a log file.  Both of these destinations may contain
+messages either from unrelated kernel or userspace activity, or kernel
+messages from non-test code that is invoked by the test.  The kernel code
+invoked by the test likely is not aware that a test is in progress and
+thus can not print the message as a diagnostic message.
+
 Nested tests
 ------------
 
@@ -186,10 +193,13 @@ starting with another KTAP version line and test plan, and end with the overall
 result. If one of the subtests fail, for example, the parent test should also
 fail.
 
-Additionally, all result lines in a subtest should be indented. One level of
+Additionally, all lines in a subtest should be indented. One level of
 indentation is two spaces: "  ". The indentation should begin at the version
 line and should end before the parent test's result line.
 
+"Unknown lines" are not considered to be lines in a subtest and thus are
+allowed to be either indented or not indented.
+
 An example of a test with two nested subtests:
 
 .. code-block::
@@ -225,9 +235,11 @@ Major differences between TAP and KTAP
 --------------------------------------
 
 Note the major differences between the TAP and KTAP specification:
-- yaml and json are not recommended in diagnostic messages
-- TODO directive not recognized
+- yaml and json are not recommended in KTAP diagnostic messages
+- TODO directive not recognized in KTAP
 - KTAP allows for an arbitrary number of tests to be nested
+- TAP includes "Unknown lines" in the category of "Anything else"
+- TAP says "Unknown lines" are "incorrect"; KTAP allows "Unknown lines"
 
 The TAP14 specification does permit nested tests, but instead of using another
 nested version line, uses a line of the form
-- 
Frank Rowand <frank.rowand@xxxxxxxx>