Re: [KTAP V2 PATCH] ktap_v2: add skip test result

From: Frank Rowand
Date: Sat Mar 11 2023 - 22:52:38 EST


On 3/10/23 16:20, Rae Moar wrote:
> Add the test result "skip" to KTAP version 2 as an alternative way to
> indicate a test was skipped.
>
> The current spec uses the "#SKIP" directive to indicate that a test was
> skipped. However, the "#SKIP" directive is not always evident when quickly
> skimming through KTAP results.
>
> The "skip" result would provide an alternative that could make it clearer
> that a test has not successfully passed because it was skipped.
>
> Before:
>
> KTAP version 1
> 1..1
> KTAP version 1
> 1..2
> ok 1 case_1
> ok 2 case_2 #SKIP
> ok 1 suite
>
> After:
>
> KTAP version 2
> 1..1
> KTAP version 2
> 1..2
> ok 1 case_1
> skip 2 case_2
> ok 1 suite
>
> Here is a link to a version of the KUnit parser that is able to parse
> the skip test result for KTAP version 2. Note this parser is still able
> to parse the "#SKIP" directive.
>
> Link: https://kunit-review.googlesource.com/c/linux/+/5689
>
> Signed-off-by: Rae Moar <rmoar@xxxxxxxxxx>
> --->
> Note: this patch is based on Frank's ktap_spec_version_2 branch.
>
> Documentation/dev-tools/ktap.rst | 27 ++++++++++++++++++---------
> 1 file changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/Documentation/dev-tools/ktap.rst b/Documentation/dev-tools/ktap.rst
> index ff77f4aaa6ef..f48aa00db8f0 100644
> --- a/Documentation/dev-tools/ktap.rst
> +++ b/Documentation/dev-tools/ktap.rst
> @@ -74,7 +74,8 @@ They are required and must have the format:
> <result> <number> [<description>][ # [<directive>] [<diagnostic data>]]
>
> The result can be either "ok", which indicates the test case passed,
> -or "not ok", which indicates that the test case failed.
> +"not ok", which indicates that the test case failed, or "skip", which indicates
> +the test case did not run.
>
> <number> represents the number of the test being performed. The first test must
> have the number 1 and the number then must increase by 1 for each additional
> @@ -91,12 +92,13 @@ A directive is a keyword that indicates a different outcome for a test other
> than passed and failed. The directive is optional, and consists of a single
> keyword preceding the diagnostic data. In the event that a parser encounters
> a directive it doesn't support, it should fall back to the "ok" / "not ok"
> -result.
> +/ "skip" result.
>
> Currently accepted directives are:
>
> -- "SKIP", which indicates a test was skipped (note the result of the test case
> - result line can be either "ok" or "not ok" if the SKIP directive is used)

> +- "SKIP", which indicates a test was skipped (note this is an alternative to
> + the "skip" result type and if the SKIP directive is used, the
> + result can be any type - "ok", "not ok", or "skip")

For the "SKIP" directive, result type of either "ok", or "not ok" reflects the
current real world usage, which is mixed. I agree is makes sense to also
allow the result type of "skip" with the "SKIP directive.

I think it would be good to deprecate the "SKIP" directive, with a scheduled
removal in the V3 specification - that would allow plenty of time for test
parsers to process both V1 and V2 data, before removing processing of V1 data.

If so, the deprecation plan should be documented.

> - "TODO", which indicates that a test is not expected to pass at the moment,
> e.g. because the feature it is testing is known to be broken. While this> directive is inherited from TAP, its use in the kernel is discouraged.
> @@ -110,7 +112,7 @@ Currently accepted directives are:
>
> The diagnostic data is a plain-text field which contains any additional details
> about why this result was produced. This is typically an error message for ERROR
> -or failed tests, or a description of missing dependencies for a SKIP result.
> +or failed tests, or a description of missing dependencies for a skipped test.
>
> The diagnostic data field is optional, and results which have neither a
> directive nor any diagnostic data do not need to include the "#" field
> @@ -130,11 +132,18 @@ The test "test_case_name" failed.
>
> ::
>
> - ok 1 test # SKIP necessary dependency unavailable
> + skip 1 test # necessary dependency unavailable

Maybe add a note that the "skip" result method is preferred over the below
"ok ... # SKIP..." example below.

>
> -The test "test" was SKIPPED with the diagnostic message "necessary dependency
> +The test "test" was skipped with the diagnostic message "necessary dependency
> unavailable".
>
> +::
> +
> + ok 1 test_2 # SKIP this test should not run
> +
> +The test "test_2" was skipped with the diagnostic message "this test
> +should not run".

Maybe add a deprecation note here.

> +
> ::
>
> not ok 1 test # TIMEOUT 30 seconds
> @@ -225,7 +234,7 @@ An example format with multiple levels of nested testing:
> not ok 1 test_1
> ok 2 test_2
> not ok 1 test_3
> - ok 2 test_4 # SKIP
> + skip 2 test_4
> not ok 1 example_test_1
> ok 2 example_test_2
>
> @@ -262,7 +271,7 @@ Example KTAP output
> ok 1 example_test_1
> KTAP version 2
> 1..2
> - ok 1 test_1 # SKIP test_1 skipped
> + skip 1 test_1 # test_1 skipped
> ok 2 test_2
> ok 2 example_test_2
> KTAP version 2
>
> base-commit: 906f02e42adfbd5ae70d328ee71656ecb602aaf5