Commit Graph

6 Commits

Author SHA1 Message Date
Daniel Latypov 65af9b964d kunit: don't show `1 == 1` in failed assertion messages
Currently, given something (fairly dystopian) like
> KUNIT_EXPECT_EQ(test, 2 + 2, 5)

KUnit will prints a failure message like this.
>  Expected 2 + 2 == 5, but
>      2 + 2 == 4
>      5 == 5

With this patch, the output just becomes
>  Expected 2 + 2 == 5, but
>      2 + 2 == 4

This patch is slightly hacky, but it's quite common* to compare an
expression to a literal integer value, so this can make KUnit less
chatty in many cases. (This patch also fixes variants like
KUNIT_EXPECT_GT, LE, et al.).

It also allocates an additional string briefly, but given this only
happens on test failures, it doesn't seem too bad a tradeoff.
Also, in most cases it'll realize the lengths are unequal and bail out
before the allocation.

We could save the result of the formatted string to avoid wasting this
extra work, but it felt cleaner to leave it as-is.

Edge case: for something silly and unrealistic like
> KUNIT_EXPECT_EQ(test, 4, 5);

It'll generate this message with a trailing "but"
>  Expected 4 == 5, but
>  <next line of normal output>

It didn't feel worth adding a check up-front to see if both sides are
literals to handle this better.

*A quick grep suggests 100+ comparisons to an integer literal as the
right hand side.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Tested-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-02-08 15:43:34 -07:00
Alan Maguire c3bba690a2 kunit: subtests should be indented 4 spaces according to TAP
Introduce KUNIT_SUBTEST_INDENT macro which corresponds to 4-space
indentation and KUNIT_SUBSUBTEST_INDENT macro which corresponds to
8-space indentation in line with TAP spec (e.g. see "Subtests"
section of https://node-tap.org/tap-protocol/).

Use these macros in place of one or two tabs in strings to clarify
why we are indenting.

Suggested-by: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-03-26 14:08:41 -06:00
David Gow 2d68df6cc4 kunit: Always print actual pointer values in asserts
KUnit assertions and expectations will print the values being tested. If
these are pointers (e.g., KUNIT_EXPECT_PTR_EQ(test, a, b)), these
pointers are currently printed with the %pK format specifier, which -- to
prevent information leaks which may compromise, e.g., ASLR -- are often
either hashed or replaced with ____ptrval____ or similar, making debugging
tests difficult.

By replacing %pK with %px as Documentation/core-api/printk-formats.rst
suggests, we disable this security feature for KUnit assertions and
expectations, allowing the actual pointer values to be printed. Given
that KUnit is not intended for use in production kernels, and the
pointers are only printed on failing tests, this seems like a worthwhile
tradeoff.

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-03-25 12:12:33 -06:00
Alan Maguire c475c77d5b kunit: allow kunit tests to be loaded as a module
As tests are added to kunit, it will become less feasible to execute
all built tests together.  By supporting modular tests we provide
a simple way to do selective execution on a running system; specifying

CONFIG_KUNIT=y
CONFIG_KUNIT_EXAMPLE_TEST=m

...means we can simply "insmod example-test.ko" to run the tests.

To achieve this we need to do the following:

o export the required symbols in kunit
o string-stream tests utilize non-exported symbols so for now we skip
  building them when CONFIG_KUNIT_TEST=m.
o drivers/base/power/qos-test.c contains a few unexported interface
  references, namely freq_qos_read_value() and freq_constraints_init().
  Both of these could be potentially defined as static inline functions
  in include/linux/pm_qos.h, but for now we simply avoid supporting
  module build for that test suite.
o support a new way of declaring test suites.  Because a module cannot
  do multiple late_initcall()s, we provide a kunit_test_suites() macro
  to declare multiple suites within the same module at once.
o some test module names would have been too general ("test-test"
  and "example-test" for kunit tests, "inode-test" for ext4 tests);
  rename these as appropriate ("kunit-test", "kunit-example-test"
  and "ext4-inode-test" respectively).

Also define kunit_test_suite() via kunit_test_suites()
as callers in other trees may need the old definition.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits
Acked-by: David Gow <davidgow@google.com> # For list-test
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-09 16:42:29 -07:00
Alan Maguire 109fb06fdc kunit: move string-stream.h to lib/kunit
string-stream interfaces are not intended for external use;
move them from include/kunit to lib/kunit accordingly.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-09 16:41:05 -07:00
Brendan Higgins 6b229e593f kunit: test: add assertion printing library
Add `struct kunit_assert` and friends which provide a structured way to
capture data from an expectation or an assertion (introduced later in
the series) so that it may be printed out in the event of a failure.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2019-09-30 17:35:00 -06:00