Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-13 Thread David Gow
On Sat, Nov 14, 2020 at 9:38 AM Arpitha Raghunandan <98.a...@gmail.com> wrote:
>
> On 14/11/20 5:44 am, Marco Elver wrote:
> >
> > Arpitha: Do you want to send v7, but with the following modifications
> > from what I proposed? Assuming nobody objects.
> >
> > 1. Remove the num_params counter and don't print the number of params
> > anymore, nor do validation that generators are deterministic.
> > 2. Remove the [].
> > [ I'm happy to send as well, just let me know what you prefer. ]
> >
> > Thanks,
> > -- Marco
> >
>
> If no objections I will send the v7 with the above changes.
> Thanks!

This sounds good to me!

Cheers,
-- David


Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-13 Thread Arpitha Raghunandan
On 14/11/20 5:44 am, Marco Elver wrote:
> On Fri, 13 Nov 2020 at 23:37, David Gow  wrote:
>>
>> On Fri, Nov 13, 2020 at 6:31 PM Marco Elver  wrote:
>>>
>>> On Fri, Nov 13, 2020 at 01:17PM +0800, David Gow wrote:
 On Thu, Nov 12, 2020 at 8:37 PM Marco Elver  wrote:
>>> [...]
>> (It also might be a little tricky with the current implementation to
>> produce the test plan, as the parameters come from a generator, and I
>> don't think there's a way of getting the number of parameters ahead of
>> time. That's a problem with the sub-subtest model, too, though at
>> least there it's a little more isolated from other tests.)
>
> The whole point of generators, as I envisage it, is to also provide the
> ability for varying parameters dependent on e.g. environment,
> configuration, number of CPUs, etc. The current array-based generator is
> the simplest possible use-case.
>
> However, we *can* require generators generate a deterministic number of
> parameters when called multiple times on the same system.

 I think this is a reasonable compromise, though it's not actually
 essential. As I understand the TAP spec, the test plan is actually
 optional (and/or can be at the end of the sequence of tests), though
 kunit_tool currently only supports having it at the beginning (which
 is strongly preferred by the spec anyway). I think we could get away
 with having it at the bottom of the subtest results though, which
 would save having to run the generator twice, when subtest support is
 added to kunit_tool.
>>>
>>> I can't find this in the TAP spec, where should I look? Perhaps we
>>> shouldn't venture too far off the beaten path, given we might not be the
>>> only ones that want to parse this output.
>>>
>>
>> It's in the "Test Lines and the Plan" section:
>> "The plan is optional but if there is a plan before the test points it
>> must be the first non-diagnostic line output by the test file. In
>> certain instances a test file may not know how many test points it
>> will ultimately be running. In this case the plan can be the last
>> non-diagnostic line in the output. The plan cannot appear in the
>> middle of the output, nor can it appear more than once."
> 
> Ah, that's fine then.
> 
>> My only concern with running through the generator multiple times to
>> get the count is that it might be slow and/or more difficult if
>> someone uses a more complicated generator. I can't think of anything
>> specific yet, though, so we can always do it for now and change it
>> later if a problematic case occurs.
> 
> I'm all for simplicity, so if nobody objects, let's just get rid of
> the number of parameters and avoid running it twice.
> 
> To that end, I propose a v7 (below) that takes care of getting number of
> parameters (and also displays descriptions for each parameter where
> available).
>
> Now it is up to you how you want to turn the output from diagnostic
> lines into something TAP compliant, because now we have the number of
> parameters and can turn it into a subsubtest. But I think kunit-tool
> doesn't understand subsubtests yet, so I suggest we take these patches,
> and then somebody can prepare kunit-tool.
>

 This sounds good to me. The only thing I'm not sure about is the
 format of the parameter description: thus far test names be valid C
 identifier names, due to the fact they're named after the test
 function. I don't think there's a fundamental reason parameters (and
 hence, potentially, subsubtests) need to follow that convention as
 well, but it does look a bit odd.  Equally, the square brackets around
 the description shouldn't be necessary according to the TAP spec, but
 do seem to make things a little more readable, particuarly with the
 names in the ext4 inode test. I'm not too worried about either of
 those, though: I'm sure it'll look fine once I've got used to it.
>>>
>>> The parameter description doesn't need to be a C identifier. At least
>>> that's what I could immediately glean from TAP v13 spec (I'm looking
>>> here: https://testanything.org/tap-version-13-specification.html and see
>>> e.g. "ok 1 - Input file opened" ...).
>>>
>>
>> Yeah: it looked a bit weird for everything else to be an identifier
>> (given that KUnit does require it for tests), but these parameter
>> descriptions not to be. It's not a problem, though, so let's go ahead
>> with it.
>>
>>> [...]
>> In any case, I'm happy to leave the final decision here to Arpitha and
>> Marco, so long as we don't actually violate the TAP/KTAP spec and
>> kunit_tool is able to read at least the top-level result. My
>> preference is still to go either with the "# [test_case->name]:
>> [ok|not ok] [index] - param-[index]", or to get rid of the
>> per-parameter results entirely for now (or just print out a diagnostic
>> message on failure). In 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-13 Thread Marco Elver
On Fri, 13 Nov 2020 at 23:37, David Gow  wrote:
>
> On Fri, Nov 13, 2020 at 6:31 PM Marco Elver  wrote:
> >
> > On Fri, Nov 13, 2020 at 01:17PM +0800, David Gow wrote:
> > > On Thu, Nov 12, 2020 at 8:37 PM Marco Elver  wrote:
> > [...]
> > > > > (It also might be a little tricky with the current implementation to
> > > > > produce the test plan, as the parameters come from a generator, and I
> > > > > don't think there's a way of getting the number of parameters ahead of
> > > > > time. That's a problem with the sub-subtest model, too, though at
> > > > > least there it's a little more isolated from other tests.)
> > > >
> > > > The whole point of generators, as I envisage it, is to also provide the
> > > > ability for varying parameters dependent on e.g. environment,
> > > > configuration, number of CPUs, etc. The current array-based generator is
> > > > the simplest possible use-case.
> > > >
> > > > However, we *can* require generators generate a deterministic number of
> > > > parameters when called multiple times on the same system.
> > >
> > > I think this is a reasonable compromise, though it's not actually
> > > essential. As I understand the TAP spec, the test plan is actually
> > > optional (and/or can be at the end of the sequence of tests), though
> > > kunit_tool currently only supports having it at the beginning (which
> > > is strongly preferred by the spec anyway). I think we could get away
> > > with having it at the bottom of the subtest results though, which
> > > would save having to run the generator twice, when subtest support is
> > > added to kunit_tool.
> >
> > I can't find this in the TAP spec, where should I look? Perhaps we
> > shouldn't venture too far off the beaten path, given we might not be the
> > only ones that want to parse this output.
> >
>
> It's in the "Test Lines and the Plan" section:
> "The plan is optional but if there is a plan before the test points it
> must be the first non-diagnostic line output by the test file. In
> certain instances a test file may not know how many test points it
> will ultimately be running. In this case the plan can be the last
> non-diagnostic line in the output. The plan cannot appear in the
> middle of the output, nor can it appear more than once."

Ah, that's fine then.

> My only concern with running through the generator multiple times to
> get the count is that it might be slow and/or more difficult if
> someone uses a more complicated generator. I can't think of anything
> specific yet, though, so we can always do it for now and change it
> later if a problematic case occurs.

I'm all for simplicity, so if nobody objects, let's just get rid of
the number of parameters and avoid running it twice.

> > > > To that end, I propose a v7 (below) that takes care of getting number of
> > > > parameters (and also displays descriptions for each parameter where
> > > > available).
> > > >
> > > > Now it is up to you how you want to turn the output from diagnostic
> > > > lines into something TAP compliant, because now we have the number of
> > > > parameters and can turn it into a subsubtest. But I think kunit-tool
> > > > doesn't understand subsubtests yet, so I suggest we take these patches,
> > > > and then somebody can prepare kunit-tool.
> > > >
> > >
> > > This sounds good to me. The only thing I'm not sure about is the
> > > format of the parameter description: thus far test names be valid C
> > > identifier names, due to the fact they're named after the test
> > > function. I don't think there's a fundamental reason parameters (and
> > > hence, potentially, subsubtests) need to follow that convention as
> > > well, but it does look a bit odd.  Equally, the square brackets around
> > > the description shouldn't be necessary according to the TAP spec, but
> > > do seem to make things a little more readable, particuarly with the
> > > names in the ext4 inode test. I'm not too worried about either of
> > > those, though: I'm sure it'll look fine once I've got used to it.
> >
> > The parameter description doesn't need to be a C identifier. At least
> > that's what I could immediately glean from TAP v13 spec (I'm looking
> > here: https://testanything.org/tap-version-13-specification.html and see
> > e.g. "ok 1 - Input file opened" ...).
> >
>
> Yeah: it looked a bit weird for everything else to be an identifier
> (given that KUnit does require it for tests), but these parameter
> descriptions not to be. It's not a problem, though, so let's go ahead
> with it.
>
> > [...]
> > > > > In any case, I'm happy to leave the final decision here to Arpitha and
> > > > > Marco, so long as we don't actually violate the TAP/KTAP spec and
> > > > > kunit_tool is able to read at least the top-level result. My
> > > > > preference is still to go either with the "# [test_case->name]:
> > > > > [ok|not ok] [index] - param-[index]", or to get rid of the
> > > > > per-parameter results entirely for now (or just print out a diagnostic
> > > > > message on 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-13 Thread David Gow
On Fri, Nov 13, 2020 at 6:31 PM Marco Elver  wrote:
>
> On Fri, Nov 13, 2020 at 01:17PM +0800, David Gow wrote:
> > On Thu, Nov 12, 2020 at 8:37 PM Marco Elver  wrote:
> [...]
> > > > (It also might be a little tricky with the current implementation to
> > > > produce the test plan, as the parameters come from a generator, and I
> > > > don't think there's a way of getting the number of parameters ahead of
> > > > time. That's a problem with the sub-subtest model, too, though at
> > > > least there it's a little more isolated from other tests.)
> > >
> > > The whole point of generators, as I envisage it, is to also provide the
> > > ability for varying parameters dependent on e.g. environment,
> > > configuration, number of CPUs, etc. The current array-based generator is
> > > the simplest possible use-case.
> > >
> > > However, we *can* require generators generate a deterministic number of
> > > parameters when called multiple times on the same system.
> >
> > I think this is a reasonable compromise, though it's not actually
> > essential. As I understand the TAP spec, the test plan is actually
> > optional (and/or can be at the end of the sequence of tests), though
> > kunit_tool currently only supports having it at the beginning (which
> > is strongly preferred by the spec anyway). I think we could get away
> > with having it at the bottom of the subtest results though, which
> > would save having to run the generator twice, when subtest support is
> > added to kunit_tool.
>
> I can't find this in the TAP spec, where should I look? Perhaps we
> shouldn't venture too far off the beaten path, given we might not be the
> only ones that want to parse this output.
>

It's in the "Test Lines and the Plan" section:
"The plan is optional but if there is a plan before the test points it
must be the first non-diagnostic line output by the test file. In
certain instances a test file may not know how many test points it
will ultimately be running. In this case the plan can be the last
non-diagnostic line in the output. The plan cannot appear in the
middle of the output, nor can it appear more than once."

My only concern with running through the generator multiple times to
get the count is that it might be slow and/or more difficult if
someone uses a more complicated generator. I can't think of anything
specific yet, though, so we can always do it for now and change it
later if a problematic case occurs.

> > > To that end, I propose a v7 (below) that takes care of getting number of
> > > parameters (and also displays descriptions for each parameter where
> > > available).
> > >
> > > Now it is up to you how you want to turn the output from diagnostic
> > > lines into something TAP compliant, because now we have the number of
> > > parameters and can turn it into a subsubtest. But I think kunit-tool
> > > doesn't understand subsubtests yet, so I suggest we take these patches,
> > > and then somebody can prepare kunit-tool.
> > >
> >
> > This sounds good to me. The only thing I'm not sure about is the
> > format of the parameter description: thus far test names be valid C
> > identifier names, due to the fact they're named after the test
> > function. I don't think there's a fundamental reason parameters (and
> > hence, potentially, subsubtests) need to follow that convention as
> > well, but it does look a bit odd.  Equally, the square brackets around
> > the description shouldn't be necessary according to the TAP spec, but
> > do seem to make things a little more readable, particuarly with the
> > names in the ext4 inode test. I'm not too worried about either of
> > those, though: I'm sure it'll look fine once I've got used to it.
>
> The parameter description doesn't need to be a C identifier. At least
> that's what I could immediately glean from TAP v13 spec (I'm looking
> here: https://testanything.org/tap-version-13-specification.html and see
> e.g. "ok 1 - Input file opened" ...).
>

Yeah: it looked a bit weird for everything else to be an identifier
(given that KUnit does require it for tests), but these parameter
descriptions not to be. It's not a problem, though, so let's go ahead
with it.

> [...]
> > > > In any case, I'm happy to leave the final decision here to Arpitha and
> > > > Marco, so long as we don't actually violate the TAP/KTAP spec and
> > > > kunit_tool is able to read at least the top-level result. My
> > > > preference is still to go either with the "# [test_case->name]:
> > > > [ok|not ok] [index] - param-[index]", or to get rid of the
> > > > per-parameter results entirely for now (or just print out a diagnostic
> > > > message on failure). In any case, it's a decision we can revisit once
> > > > we have support for named parameters, better tooling, or a better idea
> > > > of how people are actually using this.
> > >
> > > Right, so I think we'll be in a better place if we implement: 1)
> > > parameter to description conversion support, 2) counting parameters. So
> > > I decided to see 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-13 Thread Marco Elver
On Fri, Nov 13, 2020 at 01:17PM +0800, David Gow wrote:
> On Thu, Nov 12, 2020 at 8:37 PM Marco Elver  wrote:
[...]
> > > (It also might be a little tricky with the current implementation to
> > > produce the test plan, as the parameters come from a generator, and I
> > > don't think there's a way of getting the number of parameters ahead of
> > > time. That's a problem with the sub-subtest model, too, though at
> > > least there it's a little more isolated from other tests.)
> >
> > The whole point of generators, as I envisage it, is to also provide the
> > ability for varying parameters dependent on e.g. environment,
> > configuration, number of CPUs, etc. The current array-based generator is
> > the simplest possible use-case.
> >
> > However, we *can* require generators generate a deterministic number of
> > parameters when called multiple times on the same system.
> 
> I think this is a reasonable compromise, though it's not actually
> essential. As I understand the TAP spec, the test plan is actually
> optional (and/or can be at the end of the sequence of tests), though
> kunit_tool currently only supports having it at the beginning (which
> is strongly preferred by the spec anyway). I think we could get away
> with having it at the bottom of the subtest results though, which
> would save having to run the generator twice, when subtest support is
> added to kunit_tool.

I can't find this in the TAP spec, where should I look? Perhaps we
shouldn't venture too far off the beaten path, given we might not be the
only ones that want to parse this output.

> > To that end, I propose a v7 (below) that takes care of getting number of
> > parameters (and also displays descriptions for each parameter where
> > available).
> >
> > Now it is up to you how you want to turn the output from diagnostic
> > lines into something TAP compliant, because now we have the number of
> > parameters and can turn it into a subsubtest. But I think kunit-tool
> > doesn't understand subsubtests yet, so I suggest we take these patches,
> > and then somebody can prepare kunit-tool.
> >
> 
> This sounds good to me. The only thing I'm not sure about is the
> format of the parameter description: thus far test names be valid C
> identifier names, due to the fact they're named after the test
> function. I don't think there's a fundamental reason parameters (and
> hence, potentially, subsubtests) need to follow that convention as
> well, but it does look a bit odd.  Equally, the square brackets around
> the description shouldn't be necessary according to the TAP spec, but
> do seem to make things a little more readable, particuarly with the
> names in the ext4 inode test. I'm not too worried about either of
> those, though: I'm sure it'll look fine once I've got used to it.

The parameter description doesn't need to be a C identifier. At least
that's what I could immediately glean from TAP v13 spec (I'm looking
here: https://testanything.org/tap-version-13-specification.html and see
e.g. "ok 1 - Input file opened" ...).

[...]
> > > In any case, I'm happy to leave the final decision here to Arpitha and
> > > Marco, so long as we don't actually violate the TAP/KTAP spec and
> > > kunit_tool is able to read at least the top-level result. My
> > > preference is still to go either with the "# [test_case->name]:
> > > [ok|not ok] [index] - param-[index]", or to get rid of the
> > > per-parameter results entirely for now (or just print out a diagnostic
> > > message on failure). In any case, it's a decision we can revisit once
> > > we have support for named parameters, better tooling, or a better idea
> > > of how people are actually using this.
> >
> > Right, so I think we'll be in a better place if we implement: 1)
> > parameter to description conversion support, 2) counting parameters. So
> > I decided to see what it looks like, and it wasn't too bad. I just don't
> > know how you want to fix kunit-tool to make these non-diagnostic lines
> > and not complain, but as I said, it'd be good to not block these
> > patches.
> 
> Yup, I tried this v7, and it looks good to me. The kunit_tool work
> will probably be a touch more involved, so I definitely don't want to
> hold up supporting this on that.
> 
> My only thoughts on the v7 patch are:
> - I don't think we actually need the parameter count yet (or perhaps
> ever if we go with subtests as planned), so I be okay with getting rid
> of that.

As noted above, perhaps we should keep it for compatibility with other
parsers and CI systems we don't have much control over. It'd be a shame
if 99% of KUnit output can be parsed by some partially compliant parser,
yet this would break it.

> - It'd be a possibility to get rid of the square brackets from the
> output, and if we still want them, make them part of the test itself:
> if this were TAP formatted, those brackets would be part of the
> subsubtest name.

I don't mind. It's just that we can't prescribe a format, and as
seen below the descriptions 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-12 Thread David Gow
On Thu, Nov 12, 2020 at 8:37 PM Marco Elver  wrote:
>
> On Thu, Nov 12, 2020 at 04:18PM +0800, David Gow wrote:
> > On Thu, Nov 12, 2020 at 12:55 AM Bird, Tim  wrote:
> [...]
> > > > kunit_tool has a bug when parsing the comments / diagnostic lines,
> > > > which requires a ": " to be present. This is a bug, which is being
> > > > fixed[1], so while it's _nice_ to not trigger it, it's not really an
> > > > important long-term goal of the format. In any case, this kunit_tool
> > > > issue only affects the comment lines: if the per-parameter result line
> > > > is an actual result, rather than just a diagnostic, this shouldn't be
> > > > a problem.
> > > >
> > > > In any case, I still prefer my proposed option for now -- noting that
> > > > these per-parameter results are not actually supposed to be parsed --
> > > > with then the possibility of expanding them to actual nested results
> > > > later should we wish. But if the idea of having TAP-like lines in
> > > > diagnostics seems too dangerous (e.g. because people will try to parse
> > > > them anyway), then I think the options we have are to stick to the
> > > > output format given in the current version of this patch (which
> > > > doesn't resemble a TAP result), make each parameterised version its
> > > > own test (without a "container test", which would require a bit of
> > > > extra work while computing test plans), or to hold this whole feature
> > > > back until we can support arbitrary test hierarchies in KUnit.
> > > It seems like you're missing a 4th option, which is just tack the 
> > > parameter
> > > name on, without using a colon, and have these testcases treated
> > > as unique within the context of the super-test.  Is there some reason
> > > these can't be expressed as individual testcases in the parent test?
> > >
> >
> > No: there's no fundamental reason why we couldn't do that, though
> > there are some things which make it suboptiomal, IMHO.
> >
> > Firstly, there could be a lot of parameters, and that by not grouping
> > them together it could make dealing with the results a little
> > unwieldy. The other side of that is that it'll result in tests being
> > split up and renamed as they're ported to use this, whereas if the
> > whole test shows up once (with subtests or without), the old test name
> > can still be there, with a single PASS/FAIL for the whole test.
>
> Agree, it's suboptimal and having the parameterized not be absorbed by
> the whole suite would be strongly preferred.
>
> > (It also might be a little tricky with the current implementation to
> > produce the test plan, as the parameters come from a generator, and I
> > don't think there's a way of getting the number of parameters ahead of
> > time. That's a problem with the sub-subtest model, too, though at
> > least there it's a little more isolated from other tests.)
>
> The whole point of generators, as I envisage it, is to also provide the
> ability for varying parameters dependent on e.g. environment,
> configuration, number of CPUs, etc. The current array-based generator is
> the simplest possible use-case.
>
> However, we *can* require generators generate a deterministic number of
> parameters when called multiple times on the same system.

I think this is a reasonable compromise, though it's not actually
essential. As I understand the TAP spec, the test plan is actually
optional (and/or can be at the end of the sequence of tests), though
kunit_tool currently only supports having it at the beginning (which
is strongly preferred by the spec anyway). I think we could get away
with having it at the bottom of the subtest results though, which
would save having to run the generator twice, when subtest support is
added to kunit_tool.

> To that end, I propose a v7 (below) that takes care of getting number of
> parameters (and also displays descriptions for each parameter where
> available).
>
> Now it is up to you how you want to turn the output from diagnostic
> lines into something TAP compliant, because now we have the number of
> parameters and can turn it into a subsubtest. But I think kunit-tool
> doesn't understand subsubtests yet, so I suggest we take these patches,
> and then somebody can prepare kunit-tool.
>

This sounds good to me. The only thing I'm not sure about is the
format of the parameter description: thus far test names be valid C
identifier names, due to the fact they're named after the test
function. I don't think there's a fundamental reason parameters (and
hence, potentially, subsubtests) need to follow that convention as
well, but it does look a bit odd.  Equally, the square brackets around
the description shouldn't be necessary according to the TAP spec, but
do seem to make things a little more readable, particuarly with the
names in the ext4 inode test. I'm not too worried about either of
those, though: I'm sure it'll look fine once I've got used to it.



> Or did I miss something else?
>
> > > > Personally, I'd rather not hold this feature 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-12 Thread Marco Elver
On Thu, Nov 12, 2020 at 04:18PM +0800, David Gow wrote:
> On Thu, Nov 12, 2020 at 12:55 AM Bird, Tim  wrote:
[...]
> > > kunit_tool has a bug when parsing the comments / diagnostic lines,
> > > which requires a ": " to be present. This is a bug, which is being
> > > fixed[1], so while it's _nice_ to not trigger it, it's not really an
> > > important long-term goal of the format. In any case, this kunit_tool
> > > issue only affects the comment lines: if the per-parameter result line
> > > is an actual result, rather than just a diagnostic, this shouldn't be
> > > a problem.
> > >
> > > In any case, I still prefer my proposed option for now -- noting that
> > > these per-parameter results are not actually supposed to be parsed --
> > > with then the possibility of expanding them to actual nested results
> > > later should we wish. But if the idea of having TAP-like lines in
> > > diagnostics seems too dangerous (e.g. because people will try to parse
> > > them anyway), then I think the options we have are to stick to the
> > > output format given in the current version of this patch (which
> > > doesn't resemble a TAP result), make each parameterised version its
> > > own test (without a "container test", which would require a bit of
> > > extra work while computing test plans), or to hold this whole feature
> > > back until we can support arbitrary test hierarchies in KUnit.
> > It seems like you're missing a 4th option, which is just tack the parameter
> > name on, without using a colon, and have these testcases treated
> > as unique within the context of the super-test.  Is there some reason
> > these can't be expressed as individual testcases in the parent test?
> >
> 
> No: there's no fundamental reason why we couldn't do that, though
> there are some things which make it suboptiomal, IMHO.
>
> Firstly, there could be a lot of parameters, and that by not grouping
> them together it could make dealing with the results a little
> unwieldy. The other side of that is that it'll result in tests being
> split up and renamed as they're ported to use this, whereas if the
> whole test shows up once (with subtests or without), the old test name
> can still be there, with a single PASS/FAIL for the whole test.

Agree, it's suboptimal and having the parameterized not be absorbed by
the whole suite would be strongly preferred.

> (It also might be a little tricky with the current implementation to
> produce the test plan, as the parameters come from a generator, and I
> don't think there's a way of getting the number of parameters ahead of
> time. That's a problem with the sub-subtest model, too, though at
> least there it's a little more isolated from other tests.)

The whole point of generators, as I envisage it, is to also provide the
ability for varying parameters dependent on e.g. environment,
configuration, number of CPUs, etc. The current array-based generator is
the simplest possible use-case.

However, we *can* require generators generate a deterministic number of
parameters when called multiple times on the same system.

To that end, I propose a v7 (below) that takes care of getting number of
parameters (and also displays descriptions for each parameter where
available).

Now it is up to you how you want to turn the output from diagnostic
lines into something TAP compliant, because now we have the number of
parameters and can turn it into a subsubtest. But I think kunit-tool
doesn't understand subsubtests yet, so I suggest we take these patches,
and then somebody can prepare kunit-tool.

Or did I miss something else?

> > > Personally, I'd rather not hold this feature back, and prefer to have
> > > a single combined result available, so would just stick with v6 if
> > > so...
> > >
> > > Does that make sense?
> >
> > I understand what you are saying, but this seems like a step backwards.
> > We already know that having just numbers to represent a test case is not
> > very human friendly. The same will go for these parameter case numbers.
> > I admit to not following this kunit test parameterization effort, so I don't
> > know the background of how the numbers relate to the parameters.
> > But there must be some actual semantic meaning to each of the parameter
> > cases.  Not conveying that meaning as part of the test case name seems like
> > a missed opportunity.
> 
> Yeah: I'm not a big fan of just numbering the parameters either: the
> plan is to eventually support naming these. Basically, the goal is to
> be able to run the same test code repeatedly with different inputs
> (which may be programmatically generated): depending on the testcase /
> parameter generator in question, the numbers may mean something
> specific, but it's not necessarily the case. Certainly in most cases,
> the order of these parameters is unlikely to matter, so having the
> number be part of the test name isn't ideal there: it's unlikely to
> have semantic meaning, and worst-case could be unstable due to code
> changes.

We can 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-12 Thread David Gow
On Thu, Nov 12, 2020 at 12:55 AM Bird, Tim  wrote:
>
>
>
> > -Original Message-
> > From: David Gow 
> >
> > On Wed, Nov 11, 2020 at 1:02 AM Bird, Tim  wrote:
> > >
> > > > -Original Message-
> > > > From: David Gow 
> > > >
> > > > On Mon, Nov 9, 2020 at 2:49 PM Arpitha Raghunandan <98.a...@gmail.com> 
> > > > wrote:
> > > > >
> > > > > On 07/11/20 3:36 pm, Marco Elver wrote:
> > > > > > On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> > > > > >> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan 
> > > > > >> <98.a...@gmail.com> wrote:
> > > > > >>>
> > > > > >>> Implementation of support for parameterized testing in KUnit.
> > > > > >>> This approach requires the creation of a test case using the
> > > > > >>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> > > > > >>> This generator function should return the next parameter given the
> > > > > >>> previous parameter in parameterized tests. It also provides
> > > > > >>> a macro to generate common-case generators.
> > > > > >>>
> > > > > >>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> > > > > >>> Co-developed-by: Marco Elver 
> > > > > >>> Signed-off-by: Marco Elver 
> > > > > >>> ---
> > > > > >>
> > > > > >> This looks good to me! A couple of minor thoughts about the output
> > > > > >> format below, but I'm quite happy to have this as-is regardless.
> > > > > >>
> > > > > >> Reviewed-by: David Gow 
> > > > > >>
> > > > > >> Cheers,
> > > > > >> -- David
> > > > > >>
> > > > > >>> Changes v5->v6:
> > > > > >>> - Fix alignment to maintain consistency
> > > > > >>> Changes v4->v5:
> > > > > >>> - Update kernel-doc comments.
> > > > > >>> - Use const void* for generator return and prev value types.
> > > > > >>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> > > > > >>> - Rework parameterized test case execution strategy: each 
> > > > > >>> parameter is executed
> > > > > >>>   as if it was its own test case, with its own test 
> > > > > >>> initialization and cleanup
> > > > > >>>   (init and exit are called, etc.). However, we cannot add new 
> > > > > >>> test cases per TAP
> > > > > >>>   protocol once we have already started execution. Instead, log 
> > > > > >>> the result of
> > > > > >>>   each parameter run as a diagnostic comment.
> > > > > >>> Changes v3->v4:
> > > > > >>> - Rename kunit variables
> > > > > >>> - Rename generator function helper macro
> > > > > >>> - Add documentation for generator approach
> > > > > >>> - Display test case name in case of failure along with param index
> > > > > >>> Changes v2->v3:
> > > > > >>> - Modifictaion of generator macro and method
> > > > > >>> Changes v1->v2:
> > > > > >>> - Use of a generator method to access test case parameters
> > > > > >>>
> > > > > >>>  include/kunit/test.h | 36 ++
> > > > > >>>  lib/kunit/test.c | 46 
> > > > > >>> +++-
> > > > > >>>  2 files changed, 69 insertions(+), 13 deletions(-)
> > > > > >>>
> > > > > >>> diff --git a/include/kunit/test.h b/include/kunit/test.h
> > > > > >>> index db1b0ae666c4..16616d3974f9 100644
> > > > > >>> --- a/include/kunit/test.h
> > > > > >>> +++ b/include/kunit/test.h
> > > > > >>> @@ -107,6 +107,7 @@ struct kunit;
> > > > > > [...]
> > > > > >>> -   kunit_suite_for_each_test_case(suite, test_case)
> > > > > >>> -   kunit_run_case_catch_errors(suite, test_case);
> > > > > >>> +   kunit_suite_for_each_test_case(suite, test_case) {
> > > > > >>> +   struct kunit test = { .param_value = NULL, 
> > > > > >>> .param_index = 0 };
> > > > > >>> +   bool test_success = true;
> > > > > >>> +
> > > > > >>> +   if (test_case->generate_params)
> > > > > >>> +   test.param_value = 
> > > > > >>> test_case->generate_params(NULL);
> > > > > >>> +
> > > > > >>> +   do {
> > > > > >>> +   kunit_run_case_catch_errors(suite, 
> > > > > >>> test_case, );
> > > > > >>> +   test_success &= test_case->success;
> > > > > >>> +
> > > > > >>> +   if (test_case->generate_params) {
> > > > > >>> +   kunit_log(KERN_INFO, ,
> > > > > >>> + KUNIT_SUBTEST_INDENT
> > > > > >>> + "# %s: param-%d %s",
> > > > > >>
> > > > > >> Would it make sense to have this imitate the TAP format a bit more?
> > > > > >> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> > > > > >> something like "[test_case->name]:param-[index]" or similar.
> > > > > >> If we keep it commented out and don't indent it further, it won't
> > > > > >> formally be a nested test (though if we wanted to support those 
> > > > > >> later,
> > > > > >> it'd be easy to add), but I think it would be nicer to be 
> > > > > >> consistent
> > > > > >> here.
> > > > > >
> > > > > > The previous attempt [1] at something similar 

RE: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-11 Thread Bird, Tim


> -Original Message-
> From: David Gow 
> 
> On Wed, Nov 11, 2020 at 1:02 AM Bird, Tim  wrote:
> >
> > > -Original Message-
> > > From: David Gow 
> > >
> > > On Mon, Nov 9, 2020 at 2:49 PM Arpitha Raghunandan <98.a...@gmail.com> 
> > > wrote:
> > > >
> > > > On 07/11/20 3:36 pm, Marco Elver wrote:
> > > > > On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> > > > >> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan 
> > > > >> <98.a...@gmail.com> wrote:
> > > > >>>
> > > > >>> Implementation of support for parameterized testing in KUnit.
> > > > >>> This approach requires the creation of a test case using the
> > > > >>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> > > > >>> This generator function should return the next parameter given the
> > > > >>> previous parameter in parameterized tests. It also provides
> > > > >>> a macro to generate common-case generators.
> > > > >>>
> > > > >>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> > > > >>> Co-developed-by: Marco Elver 
> > > > >>> Signed-off-by: Marco Elver 
> > > > >>> ---
> > > > >>
> > > > >> This looks good to me! A couple of minor thoughts about the output
> > > > >> format below, but I'm quite happy to have this as-is regardless.
> > > > >>
> > > > >> Reviewed-by: David Gow 
> > > > >>
> > > > >> Cheers,
> > > > >> -- David
> > > > >>
> > > > >>> Changes v5->v6:
> > > > >>> - Fix alignment to maintain consistency
> > > > >>> Changes v4->v5:
> > > > >>> - Update kernel-doc comments.
> > > > >>> - Use const void* for generator return and prev value types.
> > > > >>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> > > > >>> - Rework parameterized test case execution strategy: each parameter 
> > > > >>> is executed
> > > > >>>   as if it was its own test case, with its own test initialization 
> > > > >>> and cleanup
> > > > >>>   (init and exit are called, etc.). However, we cannot add new test 
> > > > >>> cases per TAP
> > > > >>>   protocol once we have already started execution. Instead, log the 
> > > > >>> result of
> > > > >>>   each parameter run as a diagnostic comment.
> > > > >>> Changes v3->v4:
> > > > >>> - Rename kunit variables
> > > > >>> - Rename generator function helper macro
> > > > >>> - Add documentation for generator approach
> > > > >>> - Display test case name in case of failure along with param index
> > > > >>> Changes v2->v3:
> > > > >>> - Modifictaion of generator macro and method
> > > > >>> Changes v1->v2:
> > > > >>> - Use of a generator method to access test case parameters
> > > > >>>
> > > > >>>  include/kunit/test.h | 36 ++
> > > > >>>  lib/kunit/test.c | 46 
> > > > >>> +++-
> > > > >>>  2 files changed, 69 insertions(+), 13 deletions(-)
> > > > >>>
> > > > >>> diff --git a/include/kunit/test.h b/include/kunit/test.h
> > > > >>> index db1b0ae666c4..16616d3974f9 100644
> > > > >>> --- a/include/kunit/test.h
> > > > >>> +++ b/include/kunit/test.h
> > > > >>> @@ -107,6 +107,7 @@ struct kunit;
> > > > > [...]
> > > > >>> -   kunit_suite_for_each_test_case(suite, test_case)
> > > > >>> -   kunit_run_case_catch_errors(suite, test_case);
> > > > >>> +   kunit_suite_for_each_test_case(suite, test_case) {
> > > > >>> +   struct kunit test = { .param_value = NULL, 
> > > > >>> .param_index = 0 };
> > > > >>> +   bool test_success = true;
> > > > >>> +
> > > > >>> +   if (test_case->generate_params)
> > > > >>> +   test.param_value = 
> > > > >>> test_case->generate_params(NULL);
> > > > >>> +
> > > > >>> +   do {
> > > > >>> +   kunit_run_case_catch_errors(suite, 
> > > > >>> test_case, );
> > > > >>> +   test_success &= test_case->success;
> > > > >>> +
> > > > >>> +   if (test_case->generate_params) {
> > > > >>> +   kunit_log(KERN_INFO, ,
> > > > >>> + KUNIT_SUBTEST_INDENT
> > > > >>> + "# %s: param-%d %s",
> > > > >>
> > > > >> Would it make sense to have this imitate the TAP format a bit more?
> > > > >> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> > > > >> something like "[test_case->name]:param-[index]" or similar.
> > > > >> If we keep it commented out and don't indent it further, it won't
> > > > >> formally be a nested test (though if we wanted to support those 
> > > > >> later,
> > > > >> it'd be easy to add), but I think it would be nicer to be consistent
> > > > >> here.
> > > > >
> > > > > The previous attempt [1] at something similar failed because it seems
> > > > > we'd need to teach kunit-tool new tricks [2], too.
> > > > > [1] 
> > > > > https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> > > > > [2] 
> > > > > https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread David Gow
On Wed, Nov 11, 2020 at 1:02 AM Bird, Tim  wrote:
>
>
>
> > -Original Message-
> > From: David Gow 
> >
> > On Mon, Nov 9, 2020 at 2:49 PM Arpitha Raghunandan <98.a...@gmail.com> 
> > wrote:
> > >
> > > On 07/11/20 3:36 pm, Marco Elver wrote:
> > > > On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> > > >> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> 
> > > >> wrote:
> > > >>>
> > > >>> Implementation of support for parameterized testing in KUnit.
> > > >>> This approach requires the creation of a test case using the
> > > >>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> > > >>> This generator function should return the next parameter given the
> > > >>> previous parameter in parameterized tests. It also provides
> > > >>> a macro to generate common-case generators.
> > > >>>
> > > >>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> > > >>> Co-developed-by: Marco Elver 
> > > >>> Signed-off-by: Marco Elver 
> > > >>> ---
> > > >>
> > > >> This looks good to me! A couple of minor thoughts about the output
> > > >> format below, but I'm quite happy to have this as-is regardless.
> > > >>
> > > >> Reviewed-by: David Gow 
> > > >>
> > > >> Cheers,
> > > >> -- David
> > > >>
> > > >>> Changes v5->v6:
> > > >>> - Fix alignment to maintain consistency
> > > >>> Changes v4->v5:
> > > >>> - Update kernel-doc comments.
> > > >>> - Use const void* for generator return and prev value types.
> > > >>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> > > >>> - Rework parameterized test case execution strategy: each parameter 
> > > >>> is executed
> > > >>>   as if it was its own test case, with its own test initialization 
> > > >>> and cleanup
> > > >>>   (init and exit are called, etc.). However, we cannot add new test 
> > > >>> cases per TAP
> > > >>>   protocol once we have already started execution. Instead, log the 
> > > >>> result of
> > > >>>   each parameter run as a diagnostic comment.
> > > >>> Changes v3->v4:
> > > >>> - Rename kunit variables
> > > >>> - Rename generator function helper macro
> > > >>> - Add documentation for generator approach
> > > >>> - Display test case name in case of failure along with param index
> > > >>> Changes v2->v3:
> > > >>> - Modifictaion of generator macro and method
> > > >>> Changes v1->v2:
> > > >>> - Use of a generator method to access test case parameters
> > > >>>
> > > >>>  include/kunit/test.h | 36 ++
> > > >>>  lib/kunit/test.c | 46 
> > > >>> +++-
> > > >>>  2 files changed, 69 insertions(+), 13 deletions(-)
> > > >>>
> > > >>> diff --git a/include/kunit/test.h b/include/kunit/test.h
> > > >>> index db1b0ae666c4..16616d3974f9 100644
> > > >>> --- a/include/kunit/test.h
> > > >>> +++ b/include/kunit/test.h
> > > >>> @@ -107,6 +107,7 @@ struct kunit;
> > > > [...]
> > > >>> -   kunit_suite_for_each_test_case(suite, test_case)
> > > >>> -   kunit_run_case_catch_errors(suite, test_case);
> > > >>> +   kunit_suite_for_each_test_case(suite, test_case) {
> > > >>> +   struct kunit test = { .param_value = NULL, 
> > > >>> .param_index = 0 };
> > > >>> +   bool test_success = true;
> > > >>> +
> > > >>> +   if (test_case->generate_params)
> > > >>> +   test.param_value = 
> > > >>> test_case->generate_params(NULL);
> > > >>> +
> > > >>> +   do {
> > > >>> +   kunit_run_case_catch_errors(suite, test_case, 
> > > >>> );
> > > >>> +   test_success &= test_case->success;
> > > >>> +
> > > >>> +   if (test_case->generate_params) {
> > > >>> +   kunit_log(KERN_INFO, ,
> > > >>> + KUNIT_SUBTEST_INDENT
> > > >>> + "# %s: param-%d %s",
> > > >>
> > > >> Would it make sense to have this imitate the TAP format a bit more?
> > > >> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> > > >> something like "[test_case->name]:param-[index]" or similar.
> > > >> If we keep it commented out and don't indent it further, it won't
> > > >> formally be a nested test (though if we wanted to support those later,
> > > >> it'd be easy to add), but I think it would be nicer to be consistent
> > > >> here.
> > > >
> > > > The previous attempt [1] at something similar failed because it seems
> > > > we'd need to teach kunit-tool new tricks [2], too.
> > > > [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> > > > [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> > > >
> > > > So if we go with a different format, we might need a patch before this
> > > > one to make kunit-tool compatible with that type of diagnostic.
> > > >
> > > > Currently I think we have the following proposals for a format:
> > > >
> > > > 1. The current "# 

RE: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread Bird, Tim


> -Original Message-
> From: David Gow 
> 
> On Mon, Nov 9, 2020 at 2:49 PM Arpitha Raghunandan <98.a...@gmail.com> wrote:
> >
> > On 07/11/20 3:36 pm, Marco Elver wrote:
> > > On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> > >> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> 
> > >> wrote:
> > >>>
> > >>> Implementation of support for parameterized testing in KUnit.
> > >>> This approach requires the creation of a test case using the
> > >>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> > >>> This generator function should return the next parameter given the
> > >>> previous parameter in parameterized tests. It also provides
> > >>> a macro to generate common-case generators.
> > >>>
> > >>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> > >>> Co-developed-by: Marco Elver 
> > >>> Signed-off-by: Marco Elver 
> > >>> ---
> > >>
> > >> This looks good to me! A couple of minor thoughts about the output
> > >> format below, but I'm quite happy to have this as-is regardless.
> > >>
> > >> Reviewed-by: David Gow 
> > >>
> > >> Cheers,
> > >> -- David
> > >>
> > >>> Changes v5->v6:
> > >>> - Fix alignment to maintain consistency
> > >>> Changes v4->v5:
> > >>> - Update kernel-doc comments.
> > >>> - Use const void* for generator return and prev value types.
> > >>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> > >>> - Rework parameterized test case execution strategy: each parameter is 
> > >>> executed
> > >>>   as if it was its own test case, with its own test initialization and 
> > >>> cleanup
> > >>>   (init and exit are called, etc.). However, we cannot add new test 
> > >>> cases per TAP
> > >>>   protocol once we have already started execution. Instead, log the 
> > >>> result of
> > >>>   each parameter run as a diagnostic comment.
> > >>> Changes v3->v4:
> > >>> - Rename kunit variables
> > >>> - Rename generator function helper macro
> > >>> - Add documentation for generator approach
> > >>> - Display test case name in case of failure along with param index
> > >>> Changes v2->v3:
> > >>> - Modifictaion of generator macro and method
> > >>> Changes v1->v2:
> > >>> - Use of a generator method to access test case parameters
> > >>>
> > >>>  include/kunit/test.h | 36 ++
> > >>>  lib/kunit/test.c | 46 +++-
> > >>>  2 files changed, 69 insertions(+), 13 deletions(-)
> > >>>
> > >>> diff --git a/include/kunit/test.h b/include/kunit/test.h
> > >>> index db1b0ae666c4..16616d3974f9 100644
> > >>> --- a/include/kunit/test.h
> > >>> +++ b/include/kunit/test.h
> > >>> @@ -107,6 +107,7 @@ struct kunit;
> > > [...]
> > >>> -   kunit_suite_for_each_test_case(suite, test_case)
> > >>> -   kunit_run_case_catch_errors(suite, test_case);
> > >>> +   kunit_suite_for_each_test_case(suite, test_case) {
> > >>> +   struct kunit test = { .param_value = NULL, .param_index 
> > >>> = 0 };
> > >>> +   bool test_success = true;
> > >>> +
> > >>> +   if (test_case->generate_params)
> > >>> +   test.param_value = 
> > >>> test_case->generate_params(NULL);
> > >>> +
> > >>> +   do {
> > >>> +   kunit_run_case_catch_errors(suite, test_case, 
> > >>> );
> > >>> +   test_success &= test_case->success;
> > >>> +
> > >>> +   if (test_case->generate_params) {
> > >>> +   kunit_log(KERN_INFO, ,
> > >>> + KUNIT_SUBTEST_INDENT
> > >>> + "# %s: param-%d %s",
> > >>
> > >> Would it make sense to have this imitate the TAP format a bit more?
> > >> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> > >> something like "[test_case->name]:param-[index]" or similar.
> > >> If we keep it commented out and don't indent it further, it won't
> > >> formally be a nested test (though if we wanted to support those later,
> > >> it'd be easy to add), but I think it would be nicer to be consistent
> > >> here.
> > >
> > > The previous attempt [1] at something similar failed because it seems
> > > we'd need to teach kunit-tool new tricks [2], too.
> > > [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> > > [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> > >
> > > So if we go with a different format, we might need a patch before this
> > > one to make kunit-tool compatible with that type of diagnostic.
> > >
> > > Currently I think we have the following proposals for a format:
> > >
> > > 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
> > > this works well, because no changes to kunit-tool are required, and it
> > > also picks up the diagnostic context for the case and displays that on
> > > test failure.
> > >
> > > 2. Your proposed "# [ok|not ok] - 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread Arpitha Raghunandan
On 10/11/20 10:11 pm, Marco Elver wrote:
> On Tue, 10 Nov 2020 at 17:32, Arpitha Raghunandan <98.a...@gmail.com> wrote:
>>
>> On 10/11/20 4:05 pm, Marco Elver wrote:
>>> On Tue, 10 Nov 2020 at 08:21, David Gow  wrote:
>>> [...]
>>
>> The previous attempt [1] at something similar failed because it seems
>> we'd need to teach kunit-tool new tricks [2], too.
>> [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
>> [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
>>
>> So if we go with a different format, we might need a patch before this
>> one to make kunit-tool compatible with that type of diagnostic.
>>
>> Currently I think we have the following proposals for a format:
>>
>> 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
>> this works well, because no changes to kunit-tool are required, and it
>> also picks up the diagnostic context for the case and displays that on
>> test failure.
>>
>> 2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
>> As-is, this needs a patch for kunit-tool as well. I just checked, and
>> if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
>> (note the space after ':') it works without changing kunit-tool. ;-)
>>
>> 3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
>> which I had played with earlier but kunit-tool is definitely not yet
>> happy with.
>>
>> So my current preference is (2) with the extra space (no change to
>> kunit-tool required). WDYT?
>>

 Hmm… that failure in kunit_tool is definitely a bug: we shouldn't care
 what comes after the comment character except if it's an explicit
 subtest declaration or a crash. I'll try to put a patch together to
 fix it, but I'd rather not delay this just for that.

 In any thought about this a bit more, It turns out that the proposed
 KTAP spec[1] discourages the use of ':', except as part of a subtest
 declaration, or perhaps an as-yet-unspecified fully-qualified test
 name. The latter is what I was going for, but if it's actively
 breaking kunit_tool, we might want to hold off on it.

 If we were to try to treat these as subtests in accordance with that
 spec, the way we'd want to use one of these options:
 A) "[ok|not ok] [index] - param-[index]" -- This doesn't mention the
 test case name, but otherwise treats things exactly the same way we
 treat existing subtests.

 B) "[ok|not ok] [index] - [test_case->name]" -- This doesn't name the
 "subtest", just gives repeated results with the same name.

 C) "[ok|not ok] [index] - [test_case->name][separator]param-[index]"
 -- This is equivalent to my suggestion with a separator of ":", or 2
 above with a separator of ": ". The in-progress spec doesn't yet
 specify how these fully-qualified names would work, other than that
 they'd use a colon somewhere, and if we comment it out, ": " is
 required.

>
> Which format do we finally go with?
>

 I'm actually going to make another wild suggestion for this, which is
 a combination of (1) and (A):
 "# [test_case->name]: [ok|not ok] [index] - param-[index]"

 This gives us a KTAP-compliant result line, except prepended with "#
 [test_case->name]: ", which makes it formally a diagnostic line,
 rather than an actual subtest. Putting the test name at the start
 matches what kunit_tool is expecting at the moment. If we then want to
 turn it into a proper subtest, we can just get rid of that prefix (and
 add the appropriate counts elsewhere).

 Does that sound good?
>>>
>>> Sounds reasonable to me!  The repetition of [index] seems unnecessary
>>> for now, but I think if we at some point have a way to get a string
>>> representation of a param, we can substitute param-[index] with a
>>> string that represents the param.
>>>
>>
>> So, with this the inode-test.c will have the following output, right?
>>
>> TAP version 14
>> 1..7
>> # Subtest: ext4_inode_test
>> 1..1
>> # inode_test_xtimestamp_decoding: ok 0 - param-0
> 
> So the params should certainly be 0-indexed, but I think TAP starts
> counting at 1, so maybe this should be:
> 
> # inode_test_xtimestamp_decoding: ok 1 - param-0
> 
> and so on... ?
> 
> Right now it doesn't matter, but it will if we make these subsubtests
> as David suggested.
> 

Okay yes, I will make the first index (following [ok|not ok]) start with 1
and let the params remain 0-indexed.
Thanks!

>> # inode_test_xtimestamp_decoding: ok 1 - param-1
>> # inode_test_xtimestamp_decoding: ok 2 - param-2
>> # inode_test_xtimestamp_decoding: ok 3 - param-3
>> # inode_test_xtimestamp_decoding: ok 4 - param-4
>> # inode_test_xtimestamp_decoding: ok 5 - param-5
>> # inode_test_xtimestamp_decoding: 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread Marco Elver
On Tue, 10 Nov 2020 at 17:32, Arpitha Raghunandan <98.a...@gmail.com> wrote:
>
> On 10/11/20 4:05 pm, Marco Elver wrote:
> > On Tue, 10 Nov 2020 at 08:21, David Gow  wrote:
> > [...]
> 
>  The previous attempt [1] at something similar failed because it seems
>  we'd need to teach kunit-tool new tricks [2], too.
>  [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
>  [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> 
>  So if we go with a different format, we might need a patch before this
>  one to make kunit-tool compatible with that type of diagnostic.
> 
>  Currently I think we have the following proposals for a format:
> 
>  1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
>  this works well, because no changes to kunit-tool are required, and it
>  also picks up the diagnostic context for the case and displays that on
>  test failure.
> 
>  2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
>  As-is, this needs a patch for kunit-tool as well. I just checked, and
>  if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
>  (note the space after ':') it works without changing kunit-tool. ;-)
> 
>  3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
>  which I had played with earlier but kunit-tool is definitely not yet
>  happy with.
> 
>  So my current preference is (2) with the extra space (no change to
>  kunit-tool required). WDYT?
> 
> >>
> >> Hmm… that failure in kunit_tool is definitely a bug: we shouldn't care
> >> what comes after the comment character except if it's an explicit
> >> subtest declaration or a crash. I'll try to put a patch together to
> >> fix it, but I'd rather not delay this just for that.
> >>
> >> In any thought about this a bit more, It turns out that the proposed
> >> KTAP spec[1] discourages the use of ':', except as part of a subtest
> >> declaration, or perhaps an as-yet-unspecified fully-qualified test
> >> name. The latter is what I was going for, but if it's actively
> >> breaking kunit_tool, we might want to hold off on it.
> >>
> >> If we were to try to treat these as subtests in accordance with that
> >> spec, the way we'd want to use one of these options:
> >> A) "[ok|not ok] [index] - param-[index]" -- This doesn't mention the
> >> test case name, but otherwise treats things exactly the same way we
> >> treat existing subtests.
> >>
> >> B) "[ok|not ok] [index] - [test_case->name]" -- This doesn't name the
> >> "subtest", just gives repeated results with the same name.
> >>
> >> C) "[ok|not ok] [index] - [test_case->name][separator]param-[index]"
> >> -- This is equivalent to my suggestion with a separator of ":", or 2
> >> above with a separator of ": ". The in-progress spec doesn't yet
> >> specify how these fully-qualified names would work, other than that
> >> they'd use a colon somewhere, and if we comment it out, ": " is
> >> required.
> >>
> >>>
> >>> Which format do we finally go with?
> >>>
> >>
> >> I'm actually going to make another wild suggestion for this, which is
> >> a combination of (1) and (A):
> >> "# [test_case->name]: [ok|not ok] [index] - param-[index]"
> >>
> >> This gives us a KTAP-compliant result line, except prepended with "#
> >> [test_case->name]: ", which makes it formally a diagnostic line,
> >> rather than an actual subtest. Putting the test name at the start
> >> matches what kunit_tool is expecting at the moment. If we then want to
> >> turn it into a proper subtest, we can just get rid of that prefix (and
> >> add the appropriate counts elsewhere).
> >>
> >> Does that sound good?
> >
> > Sounds reasonable to me!  The repetition of [index] seems unnecessary
> > for now, but I think if we at some point have a way to get a string
> > representation of a param, we can substitute param-[index] with a
> > string that represents the param.
> >
>
> So, with this the inode-test.c will have the following output, right?
>
> TAP version 14
> 1..7
> # Subtest: ext4_inode_test
> 1..1
> # inode_test_xtimestamp_decoding: ok 0 - param-0

So the params should certainly be 0-indexed, but I think TAP starts
counting at 1, so maybe this should be:

# inode_test_xtimestamp_decoding: ok 1 - param-0

and so on... ?

Right now it doesn't matter, but it will if we make these subsubtests
as David suggested.

> # inode_test_xtimestamp_decoding: ok 1 - param-1
> # inode_test_xtimestamp_decoding: ok 2 - param-2
> # inode_test_xtimestamp_decoding: ok 3 - param-3
> # inode_test_xtimestamp_decoding: ok 4 - param-4
> # inode_test_xtimestamp_decoding: ok 5 - param-5
> # inode_test_xtimestamp_decoding: ok 6 - param-6
> # inode_test_xtimestamp_decoding: ok 7 - param-7
> # inode_test_xtimestamp_decoding: ok 8 - param-8
> # inode_test_xtimestamp_decoding: ok 9 - param-9
> # 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread Arpitha Raghunandan
On 10/11/20 4:05 pm, Marco Elver wrote:
> On Tue, 10 Nov 2020 at 08:21, David Gow  wrote:
> [...]

 The previous attempt [1] at something similar failed because it seems
 we'd need to teach kunit-tool new tricks [2], too.
 [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
 [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com

 So if we go with a different format, we might need a patch before this
 one to make kunit-tool compatible with that type of diagnostic.

 Currently I think we have the following proposals for a format:

 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
 this works well, because no changes to kunit-tool are required, and it
 also picks up the diagnostic context for the case and displays that on
 test failure.

 2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
 As-is, this needs a patch for kunit-tool as well. I just checked, and
 if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
 (note the space after ':') it works without changing kunit-tool. ;-)

 3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
 which I had played with earlier but kunit-tool is definitely not yet
 happy with.

 So my current preference is (2) with the extra space (no change to
 kunit-tool required). WDYT?

>>
>> Hmm… that failure in kunit_tool is definitely a bug: we shouldn't care
>> what comes after the comment character except if it's an explicit
>> subtest declaration or a crash. I'll try to put a patch together to
>> fix it, but I'd rather not delay this just for that.
>>
>> In any thought about this a bit more, It turns out that the proposed
>> KTAP spec[1] discourages the use of ':', except as part of a subtest
>> declaration, or perhaps an as-yet-unspecified fully-qualified test
>> name. The latter is what I was going for, but if it's actively
>> breaking kunit_tool, we might want to hold off on it.
>>
>> If we were to try to treat these as subtests in accordance with that
>> spec, the way we'd want to use one of these options:
>> A) "[ok|not ok] [index] - param-[index]" -- This doesn't mention the
>> test case name, but otherwise treats things exactly the same way we
>> treat existing subtests.
>>
>> B) "[ok|not ok] [index] - [test_case->name]" -- This doesn't name the
>> "subtest", just gives repeated results with the same name.
>>
>> C) "[ok|not ok] [index] - [test_case->name][separator]param-[index]"
>> -- This is equivalent to my suggestion with a separator of ":", or 2
>> above with a separator of ": ". The in-progress spec doesn't yet
>> specify how these fully-qualified names would work, other than that
>> they'd use a colon somewhere, and if we comment it out, ": " is
>> required.
>>
>>>
>>> Which format do we finally go with?
>>>
>>
>> I'm actually going to make another wild suggestion for this, which is
>> a combination of (1) and (A):
>> "# [test_case->name]: [ok|not ok] [index] - param-[index]"
>>
>> This gives us a KTAP-compliant result line, except prepended with "#
>> [test_case->name]: ", which makes it formally a diagnostic line,
>> rather than an actual subtest. Putting the test name at the start
>> matches what kunit_tool is expecting at the moment. If we then want to
>> turn it into a proper subtest, we can just get rid of that prefix (and
>> add the appropriate counts elsewhere).
>>
>> Does that sound good?
> 
> Sounds reasonable to me!  The repetition of [index] seems unnecessary
> for now, but I think if we at some point have a way to get a string
> representation of a param, we can substitute param-[index] with a
> string that represents the param.
> 

So, with this the inode-test.c will have the following output, right?

TAP version 14
1..7
# Subtest: ext4_inode_test
1..1
# inode_test_xtimestamp_decoding: ok 0 - param-0
# inode_test_xtimestamp_decoding: ok 1 - param-1
# inode_test_xtimestamp_decoding: ok 2 - param-2
# inode_test_xtimestamp_decoding: ok 3 - param-3
# inode_test_xtimestamp_decoding: ok 4 - param-4
# inode_test_xtimestamp_decoding: ok 5 - param-5
# inode_test_xtimestamp_decoding: ok 6 - param-6
# inode_test_xtimestamp_decoding: ok 7 - param-7
# inode_test_xtimestamp_decoding: ok 8 - param-8
# inode_test_xtimestamp_decoding: ok 9 - param-9
# inode_test_xtimestamp_decoding: ok 10 - param-10
# inode_test_xtimestamp_decoding: ok 11 - param-11
# inode_test_xtimestamp_decoding: ok 12 - param-12
# inode_test_xtimestamp_decoding: ok 13 - param-13
# inode_test_xtimestamp_decoding: ok 14 - param-14
# inode_test_xtimestamp_decoding: ok 15 - param-15
ok 1 - inode_test_xtimestamp_decoding
ok 1 - ext4_inode_test

I will send another patch with this change.
Thanks!

> Note that once we want to make it a real subtest, we'd need to run the
> generator twice, once to get the number of 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-10 Thread Marco Elver
On Tue, 10 Nov 2020 at 08:21, David Gow  wrote:
[...]
> > >
> > > The previous attempt [1] at something similar failed because it seems
> > > we'd need to teach kunit-tool new tricks [2], too.
> > > [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> > > [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> > >
> > > So if we go with a different format, we might need a patch before this
> > > one to make kunit-tool compatible with that type of diagnostic.
> > >
> > > Currently I think we have the following proposals for a format:
> > >
> > > 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
> > > this works well, because no changes to kunit-tool are required, and it
> > > also picks up the diagnostic context for the case and displays that on
> > > test failure.
> > >
> > > 2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
> > > As-is, this needs a patch for kunit-tool as well. I just checked, and
> > > if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
> > > (note the space after ':') it works without changing kunit-tool. ;-)
> > >
> > > 3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
> > > which I had played with earlier but kunit-tool is definitely not yet
> > > happy with.
> > >
> > > So my current preference is (2) with the extra space (no change to
> > > kunit-tool required). WDYT?
> > >
>
> Hmm… that failure in kunit_tool is definitely a bug: we shouldn't care
> what comes after the comment character except if it's an explicit
> subtest declaration or a crash. I'll try to put a patch together to
> fix it, but I'd rather not delay this just for that.
>
> In any thought about this a bit more, It turns out that the proposed
> KTAP spec[1] discourages the use of ':', except as part of a subtest
> declaration, or perhaps an as-yet-unspecified fully-qualified test
> name. The latter is what I was going for, but if it's actively
> breaking kunit_tool, we might want to hold off on it.
>
> If we were to try to treat these as subtests in accordance with that
> spec, the way we'd want to use one of these options:
> A) "[ok|not ok] [index] - param-[index]" -- This doesn't mention the
> test case name, but otherwise treats things exactly the same way we
> treat existing subtests.
>
> B) "[ok|not ok] [index] - [test_case->name]" -- This doesn't name the
> "subtest", just gives repeated results with the same name.
>
> C) "[ok|not ok] [index] - [test_case->name][separator]param-[index]"
> -- This is equivalent to my suggestion with a separator of ":", or 2
> above with a separator of ": ". The in-progress spec doesn't yet
> specify how these fully-qualified names would work, other than that
> they'd use a colon somewhere, and if we comment it out, ": " is
> required.
>
> >
> > Which format do we finally go with?
> >
>
> I'm actually going to make another wild suggestion for this, which is
> a combination of (1) and (A):
> "# [test_case->name]: [ok|not ok] [index] - param-[index]"
>
> This gives us a KTAP-compliant result line, except prepended with "#
> [test_case->name]: ", which makes it formally a diagnostic line,
> rather than an actual subtest. Putting the test name at the start
> matches what kunit_tool is expecting at the moment. If we then want to
> turn it into a proper subtest, we can just get rid of that prefix (and
> add the appropriate counts elsewhere).
>
> Does that sound good?

Sounds reasonable to me!  The repetition of [index] seems unnecessary
for now, but I think if we at some point have a way to get a string
representation of a param, we can substitute param-[index] with a
string that represents the param.

Note that once we want to make it a real subtest, we'd need to run the
generator twice, once to get the number of params and then to run the
tests. If we require that param generators are deterministic in the
number of params generated, this is not a problem.

Thanks,
-- Marco


Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-09 Thread David Gow
On Mon, Nov 9, 2020 at 2:49 PM Arpitha Raghunandan <98.a...@gmail.com> wrote:
>
> On 07/11/20 3:36 pm, Marco Elver wrote:
> > On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> >> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> 
> >> wrote:
> >>>
> >>> Implementation of support for parameterized testing in KUnit.
> >>> This approach requires the creation of a test case using the
> >>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> >>> This generator function should return the next parameter given the
> >>> previous parameter in parameterized tests. It also provides
> >>> a macro to generate common-case generators.
> >>>
> >>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> >>> Co-developed-by: Marco Elver 
> >>> Signed-off-by: Marco Elver 
> >>> ---
> >>
> >> This looks good to me! A couple of minor thoughts about the output
> >> format below, but I'm quite happy to have this as-is regardless.
> >>
> >> Reviewed-by: David Gow 
> >>
> >> Cheers,
> >> -- David
> >>
> >>> Changes v5->v6:
> >>> - Fix alignment to maintain consistency
> >>> Changes v4->v5:
> >>> - Update kernel-doc comments.
> >>> - Use const void* for generator return and prev value types.
> >>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> >>> - Rework parameterized test case execution strategy: each parameter is 
> >>> executed
> >>>   as if it was its own test case, with its own test initialization and 
> >>> cleanup
> >>>   (init and exit are called, etc.). However, we cannot add new test cases 
> >>> per TAP
> >>>   protocol once we have already started execution. Instead, log the 
> >>> result of
> >>>   each parameter run as a diagnostic comment.
> >>> Changes v3->v4:
> >>> - Rename kunit variables
> >>> - Rename generator function helper macro
> >>> - Add documentation for generator approach
> >>> - Display test case name in case of failure along with param index
> >>> Changes v2->v3:
> >>> - Modifictaion of generator macro and method
> >>> Changes v1->v2:
> >>> - Use of a generator method to access test case parameters
> >>>
> >>>  include/kunit/test.h | 36 ++
> >>>  lib/kunit/test.c | 46 +++-
> >>>  2 files changed, 69 insertions(+), 13 deletions(-)
> >>>
> >>> diff --git a/include/kunit/test.h b/include/kunit/test.h
> >>> index db1b0ae666c4..16616d3974f9 100644
> >>> --- a/include/kunit/test.h
> >>> +++ b/include/kunit/test.h
> >>> @@ -107,6 +107,7 @@ struct kunit;
> > [...]
> >>> -   kunit_suite_for_each_test_case(suite, test_case)
> >>> -   kunit_run_case_catch_errors(suite, test_case);
> >>> +   kunit_suite_for_each_test_case(suite, test_case) {
> >>> +   struct kunit test = { .param_value = NULL, .param_index = 
> >>> 0 };
> >>> +   bool test_success = true;
> >>> +
> >>> +   if (test_case->generate_params)
> >>> +   test.param_value = 
> >>> test_case->generate_params(NULL);
> >>> +
> >>> +   do {
> >>> +   kunit_run_case_catch_errors(suite, test_case, 
> >>> );
> >>> +   test_success &= test_case->success;
> >>> +
> >>> +   if (test_case->generate_params) {
> >>> +   kunit_log(KERN_INFO, ,
> >>> + KUNIT_SUBTEST_INDENT
> >>> + "# %s: param-%d %s",
> >>
> >> Would it make sense to have this imitate the TAP format a bit more?
> >> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> >> something like "[test_case->name]:param-[index]" or similar.
> >> If we keep it commented out and don't indent it further, it won't
> >> formally be a nested test (though if we wanted to support those later,
> >> it'd be easy to add), but I think it would be nicer to be consistent
> >> here.
> >
> > The previous attempt [1] at something similar failed because it seems
> > we'd need to teach kunit-tool new tricks [2], too.
> > [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> > [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> >
> > So if we go with a different format, we might need a patch before this
> > one to make kunit-tool compatible with that type of diagnostic.
> >
> > Currently I think we have the following proposals for a format:
> >
> > 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
> > this works well, because no changes to kunit-tool are required, and it
> > also picks up the diagnostic context for the case and displays that on
> > test failure.
> >
> > 2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
> > As-is, this needs a patch for kunit-tool as well. I just checked, and
> > if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
> > (note the space after ':') it works without changing kunit-tool. ;-)
> >
> > 3. Something like "# [ok|not 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-08 Thread Arpitha Raghunandan
On 07/11/20 3:36 pm, Marco Elver wrote:
> On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
>> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> wrote:
>>>
>>> Implementation of support for parameterized testing in KUnit.
>>> This approach requires the creation of a test case using the
>>> KUNIT_CASE_PARAM macro that accepts a generator function as input.
>>> This generator function should return the next parameter given the
>>> previous parameter in parameterized tests. It also provides
>>> a macro to generate common-case generators.
>>>
>>> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
>>> Co-developed-by: Marco Elver 
>>> Signed-off-by: Marco Elver 
>>> ---
>>
>> This looks good to me! A couple of minor thoughts about the output
>> format below, but I'm quite happy to have this as-is regardless.
>>
>> Reviewed-by: David Gow 
>>
>> Cheers,
>> -- David
>>
>>> Changes v5->v6:
>>> - Fix alignment to maintain consistency
>>> Changes v4->v5:
>>> - Update kernel-doc comments.
>>> - Use const void* for generator return and prev value types.
>>> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
>>> - Rework parameterized test case execution strategy: each parameter is 
>>> executed
>>>   as if it was its own test case, with its own test initialization and 
>>> cleanup
>>>   (init and exit are called, etc.). However, we cannot add new test cases 
>>> per TAP
>>>   protocol once we have already started execution. Instead, log the result 
>>> of
>>>   each parameter run as a diagnostic comment.
>>> Changes v3->v4:
>>> - Rename kunit variables
>>> - Rename generator function helper macro
>>> - Add documentation for generator approach
>>> - Display test case name in case of failure along with param index
>>> Changes v2->v3:
>>> - Modifictaion of generator macro and method
>>> Changes v1->v2:
>>> - Use of a generator method to access test case parameters
>>>
>>>  include/kunit/test.h | 36 ++
>>>  lib/kunit/test.c | 46 +++-
>>>  2 files changed, 69 insertions(+), 13 deletions(-)
>>>
>>> diff --git a/include/kunit/test.h b/include/kunit/test.h
>>> index db1b0ae666c4..16616d3974f9 100644
>>> --- a/include/kunit/test.h
>>> +++ b/include/kunit/test.h
>>> @@ -107,6 +107,7 @@ struct kunit;
> [...]
>>> -   kunit_suite_for_each_test_case(suite, test_case)
>>> -   kunit_run_case_catch_errors(suite, test_case);
>>> +   kunit_suite_for_each_test_case(suite, test_case) {
>>> +   struct kunit test = { .param_value = NULL, .param_index = 0 
>>> };
>>> +   bool test_success = true;
>>> +
>>> +   if (test_case->generate_params)
>>> +   test.param_value = test_case->generate_params(NULL);
>>> +
>>> +   do {
>>> +   kunit_run_case_catch_errors(suite, test_case, 
>>> );
>>> +   test_success &= test_case->success;
>>> +
>>> +   if (test_case->generate_params) {
>>> +   kunit_log(KERN_INFO, ,
>>> + KUNIT_SUBTEST_INDENT
>>> + "# %s: param-%d %s",
>>
>> Would it make sense to have this imitate the TAP format a bit more?
>> So, have "# [ok|not ok] - [name]" as the format? [name] could be
>> something like "[test_case->name]:param-[index]" or similar.
>> If we keep it commented out and don't indent it further, it won't
>> formally be a nested test (though if we wanted to support those later,
>> it'd be easy to add), but I think it would be nicer to be consistent
>> here.
> 
> The previous attempt [1] at something similar failed because it seems
> we'd need to teach kunit-tool new tricks [2], too.
> [1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
> [2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com
> 
> So if we go with a different format, we might need a patch before this
> one to make kunit-tool compatible with that type of diagnostic.
> 
> Currently I think we have the following proposals for a format:
> 
> 1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
> this works well, because no changes to kunit-tool are required, and it
> also picks up the diagnostic context for the case and displays that on
> test failure.
> 
> 2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
> As-is, this needs a patch for kunit-tool as well. I just checked, and
> if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
> (note the space after ':') it works without changing kunit-tool. ;-)
> 
> 3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
> which I had played with earlier but kunit-tool is definitely not yet
> happy with.
> 
> So my current preference is (2) with the extra space (no change to
> kunit-tool required). WDYT?
> 

Which format do we finally go with?

>> My other suggestion -- albeit one 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-07 Thread Marco Elver
On Sat, 7 Nov 2020 at 05:58, David Gow  wrote:
> On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> wrote:
> >
> > Implementation of support for parameterized testing in KUnit.
> > This approach requires the creation of a test case using the
> > KUNIT_CASE_PARAM macro that accepts a generator function as input.
> > This generator function should return the next parameter given the
> > previous parameter in parameterized tests. It also provides
> > a macro to generate common-case generators.
> >
> > Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> > Co-developed-by: Marco Elver 
> > Signed-off-by: Marco Elver 
> > ---
>
> This looks good to me! A couple of minor thoughts about the output
> format below, but I'm quite happy to have this as-is regardless.
>
> Reviewed-by: David Gow 
>
> Cheers,
> -- David
>
> > Changes v5->v6:
> > - Fix alignment to maintain consistency
> > Changes v4->v5:
> > - Update kernel-doc comments.
> > - Use const void* for generator return and prev value types.
> > - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> > - Rework parameterized test case execution strategy: each parameter is 
> > executed
> >   as if it was its own test case, with its own test initialization and 
> > cleanup
> >   (init and exit are called, etc.). However, we cannot add new test cases 
> > per TAP
> >   protocol once we have already started execution. Instead, log the result 
> > of
> >   each parameter run as a diagnostic comment.
> > Changes v3->v4:
> > - Rename kunit variables
> > - Rename generator function helper macro
> > - Add documentation for generator approach
> > - Display test case name in case of failure along with param index
> > Changes v2->v3:
> > - Modifictaion of generator macro and method
> > Changes v1->v2:
> > - Use of a generator method to access test case parameters
> >
> >  include/kunit/test.h | 36 ++
> >  lib/kunit/test.c | 46 +++-
> >  2 files changed, 69 insertions(+), 13 deletions(-)
> >
> > diff --git a/include/kunit/test.h b/include/kunit/test.h
> > index db1b0ae666c4..16616d3974f9 100644
> > --- a/include/kunit/test.h
> > +++ b/include/kunit/test.h
> > @@ -107,6 +107,7 @@ struct kunit;
[...]
> > -   kunit_suite_for_each_test_case(suite, test_case)
> > -   kunit_run_case_catch_errors(suite, test_case);
> > +   kunit_suite_for_each_test_case(suite, test_case) {
> > +   struct kunit test = { .param_value = NULL, .param_index = 0 
> > };
> > +   bool test_success = true;
> > +
> > +   if (test_case->generate_params)
> > +   test.param_value = test_case->generate_params(NULL);
> > +
> > +   do {
> > +   kunit_run_case_catch_errors(suite, test_case, 
> > );
> > +   test_success &= test_case->success;
> > +
> > +   if (test_case->generate_params) {
> > +   kunit_log(KERN_INFO, ,
> > + KUNIT_SUBTEST_INDENT
> > + "# %s: param-%d %s",
>
> Would it make sense to have this imitate the TAP format a bit more?
> So, have "# [ok|not ok] - [name]" as the format? [name] could be
> something like "[test_case->name]:param-[index]" or similar.
> If we keep it commented out and don't indent it further, it won't
> formally be a nested test (though if we wanted to support those later,
> it'd be easy to add), but I think it would be nicer to be consistent
> here.

The previous attempt [1] at something similar failed because it seems
we'd need to teach kunit-tool new tricks [2], too.
[1] https://lkml.kernel.org/r/20201105195503.ga2399...@elver.google.com
[2] https://lkml.kernel.org/r/20201106123433.ga3563...@elver.google.com

So if we go with a different format, we might need a patch before this
one to make kunit-tool compatible with that type of diagnostic.

Currently I think we have the following proposals for a format:

1. The current "# [test_case->name]: param-[index] [ok|not ok]" --
this works well, because no changes to kunit-tool are required, and it
also picks up the diagnostic context for the case and displays that on
test failure.

2. Your proposed "# [ok|not ok] - [test_case->name]:param-[index]".
As-is, this needs a patch for kunit-tool as well. I just checked, and
if we change it to "# [ok|not ok] - [test_case->name]: param-[index]"
(note the space after ':') it works without changing kunit-tool. ;-)

3. Something like "# [ok|not ok] param-[index] - [test_case->name]",
which I had played with earlier but kunit-tool is definitely not yet
happy with.

So my current preference is (2) with the extra space (no change to
kunit-tool required). WDYT?

> My other suggestion -- albeit one outside the scope of this initial
> version -- would be to allow the "param-%d" name to be overridden
> somehow by a test. For example, the ext4 inode test 

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-06 Thread David Gow
On Sat, Nov 7, 2020 at 3:22 AM Arpitha Raghunandan <98.a...@gmail.com> wrote:
>
> Implementation of support for parameterized testing in KUnit.
> This approach requires the creation of a test case using the
> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> This generator function should return the next parameter given the
> previous parameter in parameterized tests. It also provides
> a macro to generate common-case generators.
>
> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> Co-developed-by: Marco Elver 
> Signed-off-by: Marco Elver 
> ---

This looks good to me! A couple of minor thoughts about the output
format below, but I'm quite happy to have this as-is regardless.

Reviewed-by: David Gow 

Cheers,
-- David

> Changes v5->v6:
> - Fix alignment to maintain consistency
> Changes v4->v5:
> - Update kernel-doc comments.
> - Use const void* for generator return and prev value types.
> - Add kernel-doc comment for KUNIT_ARRAY_PARAM.
> - Rework parameterized test case execution strategy: each parameter is 
> executed
>   as if it was its own test case, with its own test initialization and cleanup
>   (init and exit are called, etc.). However, we cannot add new test cases per 
> TAP
>   protocol once we have already started execution. Instead, log the result of
>   each parameter run as a diagnostic comment.
> Changes v3->v4:
> - Rename kunit variables
> - Rename generator function helper macro
> - Add documentation for generator approach
> - Display test case name in case of failure along with param index
> Changes v2->v3:
> - Modifictaion of generator macro and method
> Changes v1->v2:
> - Use of a generator method to access test case parameters
>
>  include/kunit/test.h | 36 ++
>  lib/kunit/test.c | 46 +++-
>  2 files changed, 69 insertions(+), 13 deletions(-)
>
> diff --git a/include/kunit/test.h b/include/kunit/test.h
> index db1b0ae666c4..16616d3974f9 100644
> --- a/include/kunit/test.h
> +++ b/include/kunit/test.h
> @@ -107,6 +107,7 @@ struct kunit;
>   *
>   * @run_case: the function representing the actual test case.
>   * @name: the name of the test case.
> + * @generate_params: the generator function for parameterized tests.
>   *
>   * A test case is a function with the signature,
>   * ``void (*)(struct kunit *)``
> @@ -141,6 +142,7 @@ struct kunit;
>  struct kunit_case {
> void (*run_case)(struct kunit *test);
> const char *name;
> +   const void* (*generate_params)(const void *prev);
>
> /* private: internal use only. */
> bool success;
> @@ -163,6 +165,22 @@ static inline char *kunit_status_to_string(bool status)
>   */
>  #define KUNIT_CASE(test_name) { .run_case = test_name, .name = #test_name }
>
> +/**
> + * KUNIT_CASE_PARAM - A helper for creation a parameterized  
> kunit_case
> + *
> + * @test_name: a reference to a test case function.
> + * @gen_params: a reference to a parameter generator function.
> + *
> + * The generator function ``const void* gen_params(const void *prev)`` is 
> used
> + * to lazily generate a series of arbitrarily typed values that fit into a
> + * void*. The argument @prev is the previously returned value, which should 
> be
> + * used to derive the next value; @prev is set to NULL on the initial 
> generator
> + * call.  When no more values are available, the generator must return NULL.
> + */
> +#define KUNIT_CASE_PARAM(test_name, gen_params)\
> +   { .run_case = test_name, .name = #test_name,\
> + .generate_params = gen_params }
> +
>  /**
>   * struct kunit_suite - describes a related collection of  kunit_case
>   *
> @@ -208,6 +226,10 @@ struct kunit {
> const char *name; /* Read only after initialization! */
> char *log; /* Points at case log after initialization */
> struct kunit_try_catch try_catch;
> +   /* param_value is the current parameter value for a test case. */
> +   const void *param_value;
> +   /* param_index stores the index of the parameter in parameterized 
> tests. */
> +   int param_index;
> /*
>  * success starts as true, and may only be set to false during a
>  * test case; thus, it is safe to update this across multiple
> @@ -1742,4 +1764,18 @@ do {   
>  \
> fmt,  
>  \
> ##__VA_ARGS__)
>
> +/**
> + * KUNIT_ARRAY_PARAM() - Define test parameter generator from an array.
> + * @name:  prefix for the test parameter generator function.
> + * @array: array of test parameters.
> + *
> + * Define function @name_gen_params which uses @array to generate parameters.
> + */
> +#define KUNIT_ARRAY_PARAM(name, array)   
>   \
> +   

Re: [PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-06 Thread Marco Elver
On Fri, 6 Nov 2020 at 20:22, Arpitha Raghunandan <98.a...@gmail.com> wrote:
> Implementation of support for parameterized testing in KUnit.
> This approach requires the creation of a test case using the
> KUNIT_CASE_PARAM macro that accepts a generator function as input.
> This generator function should return the next parameter given the
> previous parameter in parameterized tests. It also provides
> a macro to generate common-case generators.
>
> Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
> Co-developed-by: Marco Elver 
> Signed-off-by: Marco Elver 
> ---
[...]
>
>  include/kunit/test.h | 36 ++
>  lib/kunit/test.c | 46 +++-
>  2 files changed, 69 insertions(+), 13 deletions(-)

Looks good, thank you!

Others: Please take another look.

Thanks,
-- Marco


[PATCH v6 1/2] kunit: Support for Parameterized Testing

2020-11-06 Thread Arpitha Raghunandan
Implementation of support for parameterized testing in KUnit.
This approach requires the creation of a test case using the
KUNIT_CASE_PARAM macro that accepts a generator function as input.
This generator function should return the next parameter given the
previous parameter in parameterized tests. It also provides
a macro to generate common-case generators.

Signed-off-by: Arpitha Raghunandan <98.a...@gmail.com>
Co-developed-by: Marco Elver 
Signed-off-by: Marco Elver 
---
Changes v5->v6:
- Fix alignment to maintain consistency
Changes v4->v5:
- Update kernel-doc comments.
- Use const void* for generator return and prev value types.
- Add kernel-doc comment for KUNIT_ARRAY_PARAM.
- Rework parameterized test case execution strategy: each parameter is executed
  as if it was its own test case, with its own test initialization and cleanup
  (init and exit are called, etc.). However, we cannot add new test cases per 
TAP
  protocol once we have already started execution. Instead, log the result of
  each parameter run as a diagnostic comment.
Changes v3->v4:
- Rename kunit variables
- Rename generator function helper macro
- Add documentation for generator approach
- Display test case name in case of failure along with param index
Changes v2->v3:
- Modifictaion of generator macro and method
Changes v1->v2:
- Use of a generator method to access test case parameters

 include/kunit/test.h | 36 ++
 lib/kunit/test.c | 46 +++-
 2 files changed, 69 insertions(+), 13 deletions(-)

diff --git a/include/kunit/test.h b/include/kunit/test.h
index db1b0ae666c4..16616d3974f9 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -107,6 +107,7 @@ struct kunit;
  *
  * @run_case: the function representing the actual test case.
  * @name: the name of the test case.
+ * @generate_params: the generator function for parameterized tests.
  *
  * A test case is a function with the signature,
  * ``void (*)(struct kunit *)``
@@ -141,6 +142,7 @@ struct kunit;
 struct kunit_case {
void (*run_case)(struct kunit *test);
const char *name;
+   const void* (*generate_params)(const void *prev);
 
/* private: internal use only. */
bool success;
@@ -163,6 +165,22 @@ static inline char *kunit_status_to_string(bool status)
  */
 #define KUNIT_CASE(test_name) { .run_case = test_name, .name = #test_name }
 
+/**
+ * KUNIT_CASE_PARAM - A helper for creation a parameterized  kunit_case
+ *
+ * @test_name: a reference to a test case function.
+ * @gen_params: a reference to a parameter generator function.
+ *
+ * The generator function ``const void* gen_params(const void *prev)`` is used
+ * to lazily generate a series of arbitrarily typed values that fit into a
+ * void*. The argument @prev is the previously returned value, which should be
+ * used to derive the next value; @prev is set to NULL on the initial generator
+ * call.  When no more values are available, the generator must return NULL.
+ */
+#define KUNIT_CASE_PARAM(test_name, gen_params)\
+   { .run_case = test_name, .name = #test_name,\
+ .generate_params = gen_params }
+
 /**
  * struct kunit_suite - describes a related collection of  kunit_case
  *
@@ -208,6 +226,10 @@ struct kunit {
const char *name; /* Read only after initialization! */
char *log; /* Points at case log after initialization */
struct kunit_try_catch try_catch;
+   /* param_value is the current parameter value for a test case. */
+   const void *param_value;
+   /* param_index stores the index of the parameter in parameterized 
tests. */
+   int param_index;
/*
 * success starts as true, and may only be set to false during a
 * test case; thus, it is safe to update this across multiple
@@ -1742,4 +1764,18 @@ do { 
   \
fmt,   \
##__VA_ARGS__)
 
+/**
+ * KUNIT_ARRAY_PARAM() - Define test parameter generator from an array.
+ * @name:  prefix for the test parameter generator function.
+ * @array: array of test parameters.
+ *
+ * Define function @name_gen_params which uses @array to generate parameters.
+ */
+#define KUNIT_ARRAY_PARAM(name, array) 
\
+   static const void *name##_gen_params(const void *prev)  
\
+   {   
\
+   typeof((array)[0]) * __next = prev ? ((typeof(__next)) prev) + 
1 : (array); \
+   return __next - (array) < ARRAY_SIZE((array)) ? __next : NULL;  
\
+   }
+
 #endif /* _KUNIT_TEST_H */
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index