[PATCH v9 04/18] kunit: test: add kunit_stream a std::stream like logger
Brendan Higgins
brendanhiggins at google.com
Mon Jul 22 18:10:04 UTC 2019
On Thu, Jul 18, 2019 at 5:08 PM Brendan Higgins
<brendanhiggins at google.com> wrote:
>
> On Thu, Jul 18, 2019 at 12:22:33PM -0700, Brendan Higgins wrote:
> > On Thu, Jul 18, 2019 at 10:50 AM Stephen Boyd <sboyd at kernel.org> wrote:
> > >
> > > Quoting Brendan Higgins (2019-07-16 11:52:01)
> > > > On Tue, Jul 16, 2019 at 10:50 AM Stephen Boyd <sboyd at kernel.org> wrote:
> [...]
> > > Do you have a link to those earlier patches?
> >
> > This is the first patchset:
> >
> > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1788057.html
> >
> > In particular you can see the code for matching functions here:
> >
> > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1788073.html
> >
> > And parameter matching code here:
> >
> > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1788072.html
> >
> > https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1788086.html
> >
> > My apologies in advance, but the code at this early stage had not
> > adopted the kunit_* prefix and was still using the test_* and mock_*
> > prefix. (Hence, struct kunit_stream was known as struct test_stream).
> [...]
> > > The crux of my complaint is that the string stream API is too loosely
> > > defined to be usable. It allows tests to build up a string of
> > > unstructured information, but with certain calling constraints so we
> > > have to tread carefully. If there was more structure to the data that's
> > > being recorded then the test case runner could operate on the data
> > > without having to do string/stream operations, allocations, etc. This
> > > would make the assertion logic much more concrete and specific to kunit,
> > > instead of this small kunit wrapper that's been placed on top of string
> > > stream.
> >
> > Yeah, I can see the point of wanting something that provides more
> > structure than the raw `struct kunit_stream` interface. In fact, it is
> > something I had already started working on, when I had determined it
> > would be a large effort to capture all the variations. I was further
> > put off from the idea when I had been asked to convert the KUnit
> > intermediate format from what I was using to TAP, because, as it is,
> > the current data printed out by KUnit doesn't contain all the data I
> > would like to put in it in a way that best takes advantage of the TAP
> > specification. One problematic area in particular: TAP already
> > provides a way to present a lot of the data I would like to export,
> > but it involves JSON serialization which was an idea that some of the
> > other reviewers understandably weren't too keen on. TAP also wants to
> > report data some time after it is available, which is generally not a
> > good idea for test debug information; you want to make it available as
> > soon as you can or you risk crashing with the data still inside.
> >
> > Hence, I decided we could probably spend a good long while debating
> > how I present the information. So the idea of having a loose
> > definition seemed attractive to me in its own right since it would
> > likely conform to whatever we ended up deciding in the long run. Also,
> > all the better that it was what I already had and no one seemed to
> > mind too much.
> >
> > The only constant I expect is that `struct kunit` will likely need to
> > take an abstract object with a `commit` method, or a `format` method
> > or whatever so it could control when data was going to be printed out
> > to the user. We will probably also use a string builder in there
> > somewhere.
> >
> > > TL;DR: If we can get rid of the string stream API I'd view that as an
> > > improvement because building arbitrary strings in the kernel is complex,
> > > error prone and has calling context concerns.
> >
> > True. No argument there.
> >
> > > Is the intention that other code besides unit tests will use this string
> > > stream API to build up strings? Any targets in mind? This would be a
> > > good way to get the API merged upstream given that its 2019 and we
> > > haven't had such an API in the kernel so far.
> >
> > Someone, (was it you?) asked about code sharing with a string builder
> > thingy that was used for creating structured human readable files, but
> > that seemed like a pretty massive undertaking.
> >
> > Aside from that, no. I would kind of prefered that nobody used it for
> > anything else because I the issues you described.
> >
> > Nevertheless, I think the debate over the usefulness of the
> > string_stream and kunit_stream are separate topics. Even if we made
> > kunit_stream more structured, I am pretty sure I would want to use
> > string_stream or some variation for constructing the message.
> >
> > > An "object oriented" (strong quotes!) approach where kunit_fail_msg is
> > > the innermost struct in some assertion specific structure might work
> > > nicely and allow the test runner to call a generic 'format' function to
> > > print out the message based on the type of assertion/expectation it is.
> > > It probably would mean less code size too because the strings that are
> > > common will be in the common printing function instead of created twice,
> > > in the macros/code and then copied to the heap for the string stream.
> > >
> > > struct kunit_assert {
> > > const char *line;
> > > const char *file;
> > > const char *func;
> > > void (*format)(struct kunit_assert *assert);
> > > };
> > >
> > > struct kunit_comparison_assert {
> > > enum operator operator;
> > > const char *left;
> > > const char *right;
> > > struct kunit_assert assert;
> > > };
> > >
> > > struct kunit_bool_assert {
> > > const char *truth;
> > > const char *statement;
> > > struct kunit_assert assert;
> > > };
> > >
> > > void kunit_format_comparison(struct kunit_assert *assert)
> > > {
> > > struct kunit_comparison_assert *comp = container_of(assert, ...)
> > >
> > > kunit_printk(...)
> > > }
>
> I started poking around with your suggestion while we are waiting. A
> couple early observations:
>
> 1) It is actually easier to do than I previously thought and will probably
> help with getting more of the planned TAP output stuff working.
>
> That being said, this is still a pretty substantial undertaking and
> will likely take *at least* a week to implement and properly review.
> Assuming everything goes extremely well (no unexpected issues on my
> end, very responsive reviewers, etc).
>
> 2) It *will* eliminate the need for kunit_stream.
>
> 3) ...but, it *will not* eliminate the need for string_stream.
>
> Based on my early observations, I do think it is worth doing, but I
> don't think it is worth trying to make it in this patchset (unless I
> have already missed the window, or it is going to be open for a while):
> I do think it will make things much cleaner, but I don't think it will
> achieve your desired goal of getting rid of an unstructured
> {kunit|string}_stream style interface; it just adds a layer on top of it
> that makes it harder to misuse.
>
> I attached a patch of what I have so far at the end of this email so you
> can see what I am talking about. And of course, if you agree with my
> assessment, so we can start working on it as a future patch.
>
> A couple things in regard to the patch I attached:
>
> 1) I wrote it pretty quickly so there are almost definitely mistakes.
> You should consider it RFC. I did verify it compiles though.
>
> 2) Also, I did use kunit_stream in writing it: all occurences should be
> pretty easy to replace with string_stream; nevertheless, the reason
> for this is just to make it easier to play with the current APIs. I
> wanted to have something working before I went through a big tedious
> refactoring. So sorry if it causes any confusion.
>
> 3) I also based the patch on all the KUnit patches I have queued up
> (includes things like mocking and such) since I want to see how this
> serialization thing will work with mocks and matchers and things like
> that.
>
> > I started working on something similarish, but by the time I ended up
> > coming up with a parent object whose definition was loose enough to
> > satisfy all the properties required by the child classes it ended up
> > basically being the same as what I have now just with a more complex
> > hierarchy of message manipulation logic.
> >
> > On the other hand, I didn't have the idea of doing the parent object
> > quite the way you did and that would clean up a lot of the duplicated
> > first line logic.
> >
> > I would like to give it a try, but I am afraid I am going to get
> > sucked down a really deep rabbit hole.
> >
> > > Maybe other people have opinions here on if you should do it now or
> > > later. Future coding is not a great argument because it's hard to
> > > predict the future. On the other hand, this patchset is in good shape to
> >
> > Yeah, that's kind of why I am afraid to go down this road when I have
> > something that works now and I know works with the mocking stuff I
> > want to do.
> >
> > I would like to try your suggestion, but I want to try to make it work
> > with my mocking patches before I commit to it because otherwise I am
> > just going to have to back it out in a follow up patchset.
> >
> > > merge and I'd like to use it to write unit tests for code I maintain so
> > > I don't want to see this stall out. Sorry if I'm opening the can of
> > > worms you're talking about.
> >
> > Don't be sorry. I agree with you that the kunit_stream stuff is not very pretty.
> >
> > Shuah, have we missed the merge window for 5.3?
> >
> > I saw you only sent one PR out so far for this release, and there
> > wasn't much in it; I imagine you are going to send at least one more?
> >
> > I figure, if we still got time to try out your suggestion, Stephen, no
> > harm in trying.
> >
> > Also if we missed it, then I have another couple months to play around with it.
> >
> > What do you think?
I talked to Shuah off thread, she would like us to resolve this
discussion before accepting the patchset.
She also said that this is probably going to have to wait until v5.4.
Nevertheless, Stephen, would you mind taking a look at the patch I
posted below? I would like to get your thoughts on the sum of all the
changes I am going to have to make before I try to integrate them into
the existing patches.
Sorry for being lazy, but I suspect you won't like the first pass of
how I am doing it, and I think it will probably be easier for you to
give early feedback on it as its own change anyway.
> I attached the patch mentioned above below. Let me know what you think!
>
> Cheers!
>
> From 53d475d3d56afcf92b452c6d347dbedfa1a17d34 Mon Sep 17 00:00:00 2001
> From: Brendan Higgins <brendanhiggins at google.com>
> Date: Thu, 18 Jul 2019 16:08:52 -0700
> Subject: [PATCH v1] DO NOT MERGE: started playing around with the
> serialization api
>
> ---
> include/kunit/assert.h | 130 ++++++++++++++++++++++++++++++
> include/kunit/mock.h | 4 +
> kunit/Makefile | 3 +-
> kunit/assert.c | 179 +++++++++++++++++++++++++++++++++++++++++
> kunit/mock.c | 6 +-
> 5 files changed, 318 insertions(+), 4 deletions(-)
> create mode 100644 include/kunit/assert.h
> create mode 100644 kunit/assert.c
>
> diff --git a/include/kunit/assert.h b/include/kunit/assert.h
> new file mode 100644
> index 0000000000000..e054fdff4642f
> --- /dev/null
> +++ b/include/kunit/assert.h
> @@ -0,0 +1,130 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Assertion and expectation serialization API.
> + *
> + * Copyright (C) 2019, Google LLC.
> + * Author: Brendan Higgins <brendanhiggins at google.com>
> + */
> +
> +#ifndef _KUNIT_ASSERT_H
> +#define _KUNIT_ASSERT_H
> +
> +#include <kunit/test.h>
> +#include <kunit/mock.h>
> +
> +enum kunit_assert_type {
> + KUNIT_ASSERTION,
> + KUNIT_EXPECTATION,
> +};
> +
> +struct kunit_assert {
> + enum kunit_assert_type type;
> + const char *line;
> + const char *file;
> + struct va_format message;
> + void (*format)(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +};
> +
> +void kunit_base_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +void kunit_assert_print_msg(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_unary_assert {
> + struct kunit_assert assert;
> + const char *condition;
> + bool expected_true;
> +};
> +
> +void kunit_unary_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_ptr_not_err_assert {
> + struct kunit_assert assert;
> + const char *text;
> + void *value;
> +};
> +
> +void kunit_ptr_not_err_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_binary_assert {
> + struct kunit_assert assert;
> + const char *operation;
> + const char *left_text;
> + long long left_value;
> + const char *right_text;
> + long long right_value;
> +};
> +
> +void kunit_binary_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_binary_ptr_assert {
> + struct kunit_assert assert;
> + const char *operation;
> + const char *left_text;
> + void *left_value;
> + const char *right_text;
> + void *right_value;
> +};
> +
> +void kunit_binary_ptr_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_binary_str_assert {
> + struct kunit_assert assert;
> + const char *operation;
> + const char *left_text;
> + const char *left_value;
> + const char *right_text;
> + const char *right_value;
> +};
> +
> +void kunit_binary_str_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +struct kunit_mock_assert {
> + struct kunit_assert assert;
> +};
> +
> +struct kunit_mock_no_expectations {
> + struct kunit_mock_assert assert;
> +};
> +
> +struct kunit_mock_declaration {
> + const char *function_name;
> + const char **type_names;
> + const void **params;
> + int len;
> +};
> +
> +void kunit_mock_declaration_format(struct kunit_mock_declaration *declaration,
> + struct kunit_stream *stream);
> +
> +struct kunit_matcher_result {
> + struct kunit_assert assert;
> +};
> +
> +struct kunit_mock_failed_match {
> + struct list_head node;
> + const char *expectation_text;
> + struct kunit_matcher_result *matcher_list;
> + size_t matcher_list_len;
> +};
> +
> +void kunit_mock_failed_match_format(struct kunit_mock_failed_match *match,
> + struct kunit_stream *stream);
> +
> +struct kunit_mock_no_match {
> + struct kunit_mock_assert assert;
> + struct kunit_mock_declaration declaration;
> + struct list_head failed_match_list;
> +};
> +
> +void kunit_mock_no_match_format(struct kunit_assert *assert,
> + struct kunit_stream *stream);
> +
> +#endif /* _KUNIT_ASSERT_H */
> diff --git a/include/kunit/mock.h b/include/kunit/mock.h
> index 001b96af62f1e..52c9e427c831b 100644
> --- a/include/kunit/mock.h
> +++ b/include/kunit/mock.h
> @@ -144,6 +144,10 @@ void mock_register_formatter(struct mock_param_formatter *formatter);
>
> void mock_unregister_formatter(struct mock_param_formatter *formatter);
>
> +void mock_format_param(struct kunit_stream *stream,
> + const char *type_name,
> + const void *param);
> +
> struct mock *mock_get_global_mock(void);
>
> #define MOCK(name) name##_mock
> diff --git a/kunit/Makefile b/kunit/Makefile
> index bbf43fcfb93a9..149d856a30f04 100644
> --- a/kunit/Makefile
> +++ b/kunit/Makefile
> @@ -3,7 +3,8 @@ obj-$(CONFIG_KUNIT) += test.o \
> common-mocks.o \
> string-stream.o \
> kunit-stream.o \
> - try-catch.o
> + try-catch.o \
> + assert.o
>
> obj-$(CONFIG_KUNIT_TEST) += test-test.o \
> test-mock.o \
> diff --git a/kunit/assert.c b/kunit/assert.c
> new file mode 100644
> index 0000000000000..75bb6922a994e
> --- /dev/null
> +++ b/kunit/assert.c
> @@ -0,0 +1,179 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Assertion and expectation serialization API.
> + *
> + * Copyright (C) 2019, Google LLC.
> + * Author: Brendan Higgins <brendanhiggins at google.com>
> + */
> +#include <kunit/assert.h>
> +
> +void kunit_base_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + const char *expect_or_assert;
> +
> + if (assert->type == KUNIT_EXPECTATION)
> + expect_or_assert = "EXPECTATION";
> + else
> + expect_or_assert = "ASSERTION";
> +
> + kunit_stream_add(stream, "%s FAILED at %s:%s\n",
> + expect_or_assert, assert->file, assert->line);
> +}
> +
> +void kunit_assert_print_msg(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + if (assert->message.fmt)
> + kunit_stream_add(stream, "\n%pV", &assert->message);
> +}
> +
> +void kunit_unary_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_unary_assert *unary_assert = container_of(
> + assert, struct kunit_unary_assert, assert);
> +
> + kunit_base_assert_format(assert, stream);
> + if (unary_assert->expected_true)
> + kunit_stream_add(stream,
> + "\tExpected %s to be true, but is false\n",
> + unary_assert->condition);
> + else
> + kunit_stream_add(stream,
> + "\tExpected %s to be false, but is true\n",
> + unary_assert->condition);
> + kunit_assert_print_msg(assert, stream);
> +}
> +
> +void kunit_ptr_not_err_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_ptr_not_err_assert *ptr_assert = container_of(
> + assert, struct kunit_ptr_not_err_assert, assert);
> +
> + kunit_base_assert_format(assert, stream);
> + if (!ptr_assert->value) {
> + kunit_stream_add(stream,
> + "\tExpected %s is not null, but is\n",
> + ptr_assert->text);
> + } else if (IS_ERR(ptr_assert->value)) {
> + kunit_stream_add(stream,
> + "\tExpected %s is not error, but is: %ld\n",
> + ptr_assert->text,
> + PTR_ERR(ptr_assert->value));
> + }
> + kunit_assert_print_msg(assert, stream);
> +}
> +
> +void kunit_binary_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_binary_assert *binary_assert = container_of(
> + assert, struct kunit_binary_assert, assert);
> +
> + kunit_base_assert_format(assert, stream);
> + kunit_stream_add(stream,
> + "\tExpected %s %s %s, but\n",
> + binary_assert->left_text,
> + binary_assert->operation,
> + binary_assert->right_text);
> + kunit_stream_add(stream, "\t\t%s == %lld\n",
> + binary_assert->left_text,
> + binary_assert->left_value);
> + kunit_stream_add(stream, "\t\t%s == %lld",
> + binary_assert->right_text,
> + binary_assert->right_value);
> + kunit_assert_print_msg(assert, stream);
> +}
> +
I could probably reduce some of the code duplication here by using a
variable type struct for left_value and right_value, but that would
actually increase the usage of {kunit|string}_stream; it is probably
the right thing to do, but I wanted to get your thoughts on it first.
> +void kunit_binary_ptr_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_binary_ptr_assert *binary_assert = container_of(
> + assert, struct kunit_binary_ptr_assert, assert);
> +
> + kunit_base_assert_format(assert, stream);
> + kunit_stream_add(stream,
> + "\tExpected %s %s %s, but\n",
> + binary_assert->left_text,
> + binary_assert->operation,
> + binary_assert->right_text);
> + kunit_stream_add(stream, "\t\t%s == %pK\n",
> + binary_assert->left_text,
> + binary_assert->left_value);
> + kunit_stream_add(stream, "\t\t%s == %pK",
> + binary_assert->right_text,
> + binary_assert->right_value);
> + kunit_assert_print_msg(assert, stream);
> +}
> +
> +void kunit_binary_str_assert_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_binary_str_assert *binary_assert = container_of(
> + assert, struct kunit_binary_str_assert, assert);
> +
> + kunit_base_assert_format(assert, stream);
> + kunit_stream_add(stream,
> + "\tExpected %s %s %s, but\n",
> + binary_assert->left_text,
> + binary_assert->operation,
> + binary_assert->right_text);
> + kunit_stream_add(stream, "\t\t%s == %s\n",
> + binary_assert->left_text,
> + binary_assert->left_value);
> + kunit_stream_add(stream, "\t\t%s == %s",
> + binary_assert->right_text,
> + binary_assert->right_value);
> + kunit_assert_print_msg(assert, stream);
> +}
> +
> +void kunit_mock_declaration_format(struct kunit_mock_declaration *declaration,
> + struct kunit_stream *stream)
> +{
> + int i;
> +
> + kunit_stream_add(stream, "%s(", declaration->function_name);
> + for (i = 0; i < declaration->len; i++) {
> + mock_format_param(stream,
> + declaration->type_names[i],
> + declaration->params[i]);
> + if (i < declaration->len - 1)
> + kunit_stream_add(stream, ", ");
> + }
> + kunit_stream_add(stream, ")\n");
> +}
> +
> +void kunit_mock_failed_match_format(struct kunit_mock_failed_match *match,
> + struct kunit_stream *stream)
> +{
> + struct kunit_matcher_result *result;
> + size_t i;
> +
> + kunit_stream_add(stream,
> + "Tried expectation: %s, but\n",
> + match->expectation_text);
> + for (i = 0; i < match->matcher_list_len; i++) {
> + result = &match->matcher_list[i];
> + kunit_stream_add(stream, "\t");
> + result->assert.format(&result->assert, stream);
> + kunit_stream_add(stream, "\n");
> + }
> +}
> +
> +void kunit_mock_no_match_format(struct kunit_assert *assert,
> + struct kunit_stream *stream)
> +{
> + struct kunit_mock_assert *mock_assert = container_of(
> + assert, struct kunit_mock_assert, assert);
> + struct kunit_mock_no_match *no_match = container_of(
> + mock_assert, struct kunit_mock_no_match, assert);
> + struct kunit_mock_failed_match *expectation;
> +
> + kunit_base_assert_format(assert, stream);
> + kunit_mock_declaration_format(&no_match->declaration, stream);
> +
> + list_for_each_entry(expectation, &no_match->failed_match_list, node)
> + kunit_mock_failed_match_format(expectation, stream);
> +}
> diff --git a/kunit/mock.c b/kunit/mock.c
> index ccb0abe111402..ab441a58a918c 100644
> --- a/kunit/mock.c
> +++ b/kunit/mock.c
> @@ -269,9 +269,9 @@ struct mock_param_formatter *mock_find_formatter(const char *type_name)
> return NULL;
> }
>
> -static void mock_format_param(struct kunit_stream *stream,
> - const char *type_name,
> - const void *param)
> +void mock_format_param(struct kunit_stream *stream,
> + const char *type_name,
> + const void *param)
> {
> struct mock_param_formatter *formatter;
>
> --
> 2.22.0.657.g960e92d24f-goog
>
More information about the dri-devel
mailing list