test
— Pacote de Testes de Regressão do Python¶
Nota
O pacote test
é apenas para uso interno do Python. O mesmo está sendo documentado para o benefício dos principais desenvolvedores do Python. Qualquer uso deste pacote fora da biblioteca padrão do Python é desencorajado, pois, o código mencionado aqui pode ser alterado ou removido sem aviso prévio entre as versões do Python.
O pacote test
contém todos os testes de regressão do Python, bem como os módulos test.support
e test.regrtest
. test.support
é utilizado para aprimorar seus testes enquanto o test.regrtest
direciona a suite de testes.
Cada módulo no pacote test
cujo nome começa com test_
é um conjunto de testes para um módulo ou recurso específico. Todos os novos testes devem ser escritos usando o módulo unittest
ou doctest
. Alguns testes mais antigos são escritos usando um estilo de teste “tradicional” que compara a saída impressa a sys.stdout
. Este estilo de teste foi considerado descontinuado.
Ver também
Escrever testes unitários para o pacote test
¶
É preferível que os testes que usam o módulo unittest
sigam algumas diretrizes. Uma é nomear o módulo de teste iniciando-o com test_
e termine com o nome do módulo que está sendo testado. Os métodos de teste no módulo de teste deve começar com test_
e terminar com uma descrição do que o método está testando. Isso é necessário para que os métodos sejam reconhecidos pelo driver de teste como métodos de teste. Além disso, na string de documentação para o método deve ser incluído. Um comentário (como os # Tests function returns only True or False
) deve ser usado para fornecer documentação para testar métodos. Isso é feito porque as strings de documentação são impressas se existem e, portanto, qual teste está sendo executado não é indicado.
Um boilerplate básico é muitas vezes usado:
import unittest
from test import support
class MyTestCase1(unittest.TestCase):
# Only use setUp() and tearDown() if necessary
def setUp(self):
... code to execute in preparation for tests ...
def tearDown(self):
... code to execute to clean up after tests ...
def test_feature_one(self):
# Test feature one.
... testing code ...
def test_feature_two(self):
# Test feature two.
... testing code ...
... more test methods ...
class MyTestCase2(unittest.TestCase):
... same structure as MyTestCase1 ...
... more test classes ...
if __name__ == '__main__':
unittest.main()
Este padrão de código permite que o conjunto de testes seja executado pelo test.regrtest
, por conta própria, como um script que suporte o unittest
CLI, ou através do python -m unittest
CLI.
O objetivo do teste de regressão é tentar quebrar o código. Isso leva a algumas diretrizes que devemos seguir:
O conjunto de testes deve exercitar todas as classes, funções e constantes. Isso inclui não apenas a API externa que deve ser apresentada ao mundo exterior, mas também o código “privado”.
Os testes de Whitebox (que examinam o código que está sendo testado quando os testes estão sendo gravados) são preferidos. O teste Blackbox (que testa apenas a interface do público de usuário) não é completo o suficiente para garantir que todos os casos de limite e extremos sejam testados.
Certifique-se de que todos os valores possíveis sejam testados, incluindo os inválidos. Isso garante que não apenas todos os valores válidos são aceitos, mas também, que os valores impróprios são tratados corretamente.
Esgote o maior número possível de caminhos de código. Teste onde ocorre a ramificação e, assim, personalize a entrada para garantir que tantos caminhos diferentes pelo código sejam tomados.
Adicione um teste explícito para quaisquer bugs descobertos ao código testado. Isso garantirá que o erro não apareça novamente se o código for alterado no futuro.
Certifique-se de limpar após seus testes (como fechar e remover todos os arquivos temporários).
Se um teste depende de uma condição específica do sistema operacional, então verifica se a condição já existe antes de tentar o teste.
Importa o menor número de módulos possível e faça isso o mais rápido possível. Isso minimiza dependências externas de testes, e também minimiza possíveis comportamento anômalo dos efeitos colaterais da importação de um módulo.
Tente maximizar a reutilização de código. Ocasionalmente, os testes variam em algo tão pequeno quanto o tipo de entrada é usado. Minimize a duplicação de código criando uma subclasse básica de testes com uma classe que especifica o input:
class TestFuncAcceptsSequencesMixin: func = mySuperWhammyFunction def test_func(self): self.func(self.arg) class AcceptLists(TestFuncAcceptsSequencesMixin, unittest.TestCase): arg = [1, 2, 3] class AcceptStrings(TestFuncAcceptsSequencesMixin, unittest.TestCase): arg = 'abc' class AcceptTuples(TestFuncAcceptsSequencesMixin, unittest.TestCase): arg = (1, 2, 3)
Ao usar este padrão, lembre-se que todas as classes que herdam de
unittest.TestCase
são executadas como testes. A classeMixin
no exemplo acima não tem nenhum dado e, portanto, não pode ser executada sozinha, portanto, ela não herda deunittest.TestCase
.
Ver também
- Test Driven Development
Um livro de Kent Beck sobre escrita de testes antes do código.
Executando testes usando a interface de linha de comando¶
O pacote test
pode ser executado como um script para conduzir o conjunto de testes de regressão do Python, graças à opção -m
: python -m test. Nos bastidores, ele usa test.regrtest
; a chamada python -m test.regrtest usado nas versões anteriores do Python ainda funciona. Executar o script por si só começa a executar todos os testes de regressão no pacote test
. Ele faz isso encontrando todos os módulos no pacote cujo nome começa com test_
, importando-os e executando a função test_main()
se presente ou carregando os testes via unittest.TestLoader.loadTestsFromModule se test_main
não existir. Os nomes dos testes a serem executados também podem ser passados para o script. Especificando um teste de regressão simples (python -m test test_spam) minimizará saiba e imprima apenas se o teste passou ou falhou.
A execução de test
permite definir diretamente quais recursos estão disponíveis para os testes usarem. Você faz isso usando a opção de linha de comando -u
. Especificar all
como o valor para a opção -u
ativa todos os recursos possíveis: python -m test -uall. Se todos menos um recurso for desejado (um caso mais comum), uma lista separada por vírgulas de recursos que não são desejados pode ser listada após all
. O comando python -m test -uall,-audio,-largefile executará test
com todos os recursos, exceto os recursos audio
e largefile
. Para obter uma lista de todos os recursos e mais opções de linha de comando, execute python -m test -h.
Alguns outros meios para executar os testes de regressão dependem em qual plataforma os testes estão sendo executados. No Unix, você pode executar: programa: ‘ make test’ no diretório de mais alto nível onde o Python foi construído. No Windows, executar: programa ‘rt.bat’ do seu diretório: file: ‘PCbuild’ executará todos os testes de regressão.
test.support
— Utilitários para o conjunto de teste do Python¶
O módulo test.support
fornece suporte para a suíte de testes de regressão do Python.
Nota
test.support
is not a public module. It is documented here to help
Python developers write tests. The API of this module is subject to change
without backwards compatibility concerns between releases.
Esse módulo define as seguintes exceções:
-
exception
test.support.
TestFailed
¶ Exceção a ser levantada quando um teste falha. Isto foi descontinuado em favor dos testes baseados em
unittest
e métodos de asserção deunittest.TestCase
.
-
exception
test.support.
ResourceDenied
¶ Subclasse de
unittest.SkipTest
. Levantada quando um recurso (como uma conexão de rede) não está disponível. Levantada pela funçãorequires()
.
O módulo test.support
define as seguintes constantes:
-
test.support.
verbose
¶ True
quando a saída detalhada está habilitada. Deve ser verificado quando informações mais detalhadas são desejadas sobre um teste em execução. verbose é definido portest.regrtest
.
-
test.support.
is_jython
¶ True
se o interpretador em execução for Jython.
-
test.support.
is_android
¶ True
se o sistema é Android.
-
test.support.
unix_shell
¶ Caminho para o console se não estiver no Windows; por outro lado
None
-
test.support.
LOOPBACK_TIMEOUT
¶ Tempo limite em segundos para testes usando um servidor de rede escutando na interface de loopback local da rede como
127.0.0.1
.O tempo limite é longo o suficiente para evitar a falha do teste: leva em consideração que o cliente e o servidor podem ser executados em diferentes threads ou mesmo processos diferentes.
O tempo limite deve ser longo o suficiente para os métodos
connect()
,recv()
esend()
desocket.socket
.Seu valor padrão é 5 segundos.
Veja também
INTERNET_TIMEOUT
.
-
test.support.
INTERNET_TIMEOUT
¶ Tempo limite em segundos para solicitações de rede indo para a Internet.
O tempo limite é curto o suficiente para evitar que um teste espere muito tempo se a requisição da Internet for bloqueada por qualquer motivo.
Normalmente, um tempo limite usando
INTERNET_TIMEOUT
não deve marcar um teste como falhado, mas ignorá-lo: vejatransient_internet()
.Seu valor padrão é 1 minuto.
Veja também
LOOPBACK_TIMEOUT
.
-
test.support.
SHORT_TIMEOUT
¶ Tempo limite em segundos para marcar um teste como falho se o teste demorar “muito tempo”.
O valor do tempo limite depende da opção da linha de comando regrtest
--timeout
.Se um teste usando
SHORT_TIMEOUT
começar a falhar aleatoriamente em buildbots lentos, useLONG_TIMEOUT
.Seu valor padrão é 30 segundos.
-
test.support.
LONG_TIMEOUT
¶ Tempo limite em segundos para detectar quando um teste trava.
É longo o suficiente para reduzir o risco de falha de teste nos buildbots Python mais lentos. Não deve ser usado para marcar um teste como reprovado se o teste demorar “muito tempo”. O valor do tempo limite depende da opção de linha de comando regrtest
--timeout
.Seu valor padrão é 5 minutos.
Veja também
LOOPBACK_TIMEOUT
,INTERNET_TIMEOUT
eSHORT_TIMEOUT
.
-
test.support.
PGO
¶ Definido quando os testes podem ser ignorados quando não são úteis para PGO.
-
test.support.
PIPE_MAX_SIZE
¶ Uma constante que provavelmente é maior que o tamanho do buffer de canal do sistema operacional subjacente, para fazer o bloqueio de escritas.
-
test.support.
SOCK_MAX_SIZE
¶ Uma constante que provavelmente é maior que o tamanho do buffer de soquete do sistema operacional subjacente, para fazer o bloqueio de escritas.
-
test.support.
TEST_SUPPORT_DIR
¶ Define o diretório de mais alto nível que contém
test.support
.
-
test.support.
TEST_HOME_DIR
¶ Define o diretório de mais alto nível para o pacote de teste.
-
test.support.
TEST_DATA_DIR
¶ Define o diretório
data
de dentro do pacote de teste.
-
test.support.
MAX_Py_ssize_t
¶ Define
sys.maxsize
para grandes testes de memória.
-
test.support.
max_memuse
¶ Set by
set_memlimit()
as the memory limit for big memory tests. Limited byMAX_Py_ssize_t
.
-
test.support.
real_max_memuse
¶ Set by
set_memlimit()
as the memory limit for big memory tests. Not limited byMAX_Py_ssize_t
.
-
test.support.
MISSING_C_DOCSTRINGS
¶ Set to
True
if Python is built without docstrings (theWITH_DOC_STRINGS
macro is not defined). See theconfigure --without-doc-strings
option.See also the
HAVE_DOCSTRINGS
variable.
-
test.support.
HAVE_DOCSTRINGS
¶ Set to
True
if function docstrings are available. See thepython -OO
option, which strips docstrings of functions implemented in Python.See also the
MISSING_C_DOCSTRINGS
variable.
-
test.support.
TEST_HTTP_URL
¶ Define the URL of a dedicated HTTP server for the network tests.
-
test.support.
ALWAYS_EQ
¶ Object that is equal to anything. Used to test mixed type comparison.
-
test.support.
NEVER_EQ
¶ Object that is not equal to anything (even to
ALWAYS_EQ
). Used to test mixed type comparison.
-
test.support.
LARGEST
¶ Object that is greater than anything (except itself). Used to test mixed type comparison.
-
test.support.
SMALLEST
¶ Object that is less than anything (except itself). Used to test mixed type comparison.
O módulo test.support
define as seguintes funções:
-
test.support.
is_resource_enabled
(resource)¶ Return
True
if resource is enabled and available. The list of available resources is only set whentest.regrtest
is executing the tests.
-
test.support.
python_is_optimized
()¶ Return
True
if Python was not built with-O0
or-Og
.
-
test.support.
with_pymalloc
()¶ Return
_testcapi.WITH_PYMALLOC
.
-
test.support.
requires
(resource, msg=None)¶ Raise
ResourceDenied
if resource is not available. msg is the argument toResourceDenied
if it is raised. Always returnsTrue
if called by a function whose__name__
is'__main__'
. Used when tests are executed bytest.regrtest
.
-
test.support.
sortdict
(dict)¶ Return a repr of dict with keys sorted.
-
test.support.
findfile
(filename, subdir=None)¶ Return the path to the file named filename. If no match is found filename is returned. This does not equal a failure since it could be the path to the file.
Setting subdir indicates a relative path to use to find the file rather than looking directly in the path directories.
-
test.support.
match_test
(test)¶ Determine whether test matches the patterns set in
set_match_tests()
.
-
test.support.
set_match_tests
(accept_patterns=None, ignore_patterns=None)¶ Define match patterns on test filenames and test method names for filtering tests.
-
test.support.
run_unittest
(*classes)¶ Execute
unittest.TestCase
subclasses passed to the function. The function scans the classes for methods starting with the prefixtest_
and executes the tests individually.It is also legal to pass strings as parameters; these should be keys in
sys.modules
. Each associated module will be scanned byunittest.TestLoader.loadTestsFromModule()
. This is usually seen in the followingtest_main()
function:def test_main(): support.run_unittest(__name__)
Isso executará todos os testes definidos no módulo nomeado.
-
test.support.
run_doctest
(module, verbosity=None, optionflags=0)¶ Run
doctest.testmod()
on the given module. Return(failure_count, test_count)
.If verbosity is
None
,doctest.testmod()
is run with verbosity set toverbose
. Otherwise, it is run with verbosity set toNone
. optionflags is passed asoptionflags
todoctest.testmod()
.
-
test.support.
setswitchinterval
(interval)¶ Set the
sys.setswitchinterval()
to the given interval. Defines a minimum interval for Android systems to prevent the system from hanging.
-
test.support.
check_impl_detail
(**guards)¶ Use this check to guard CPython’s implementation-specific tests or to run them only on the implementations guarded by the arguments. This function returns
True
orFalse
depending on the host platform. Example usage:check_impl_detail() # Only on CPython (default). check_impl_detail(jython=True) # Only on Jython. check_impl_detail(cpython=False) # Everywhere except CPython.
-
test.support.
set_memlimit
(limit)¶ Define os valores para
max_memuse
ereal_max_memuse
para grandes testes de memória.
-
test.support.
record_original_stdout
(stdout)¶ Armazena o valor de stdout. Destina-se a manter o stdout no momento em que o registro começou.
-
test.support.
get_original_stdout
()¶ Retorna o stdout original definido por
record_original_stdout()
ousys.stdout
se não estiver definido.
-
test.support.
args_from_interpreter_flags
()¶ Retorna uma lista de argumentos de linha de comando reproduzindo as configurações em
sys.flags
esys.warnoptions
.
-
test.support.
optim_args_from_interpreter_flags
()¶ Retorna a lista de argumentos da linha de comando reproduzindo as configurações de otimização atuais em
sys.flags
.
-
test.support.
captured_stdin
()¶ -
test.support.
captured_stdout
()¶ -
test.support.
captured_stderr
()¶ Um gerenciador de contexto que substitui temporariamente o fluxo nomeado pelo objeto
io.StringIO
.Exemplo do uso com fluxos de saída:
with captured_stdout() as stdout, captured_stderr() as stderr: print("hello") print("error", file=sys.stderr) assert stdout.getvalue() == "hello\n" assert stderr.getvalue() == "error\n"
Exemplo de uso com fluxo de entrada:
with captured_stdin() as stdin: stdin.write('hello\n') stdin.seek(0) # call test code that consumes from sys.stdin captured = input() self.assertEqual(captured, "hello")
-
test.support.
disable_faulthandler
()¶ Um gerenciador de contexto que desativa temporariamente
faulthandler
.
-
test.support.
gc_collect
()¶ Força a coleta de tantos objetos quanto possível. Isso é necessário porque a desalocação oportuna não é garantida pelo coletor de lixo. Isso significa que os métodos
__del__
podem ser chamados mais tarde do que o esperado e as referência fraca podem permanecer ativas por mais tempo do que o esperado.
-
test.support.
disable_gc
()¶ A context manager that disables the garbage collector on entry. On exit, the garbage collector is restored to its prior state.
-
test.support.
swap_attr
(obj, attr, new_val)¶ Context manager to swap out an attribute with a new object.
Uso:
with swap_attr(obj, "attr", 5): ...
This will set
obj.attr
to 5 for the duration of thewith
block, restoring the old value at the end of the block. Ifattr
doesn’t exist onobj
, it will be created and then deleted at the end of the block.The old value (or
None
if it doesn’t exist) will be assigned to the target of the “as” clause, if there is one.
-
test.support.
swap_item
(obj, attr, new_val)¶ Context manager to swap out an item with a new object.
Uso:
with swap_item(obj, "item", 5): ...
This will set
obj["item"]
to 5 for the duration of thewith
block, restoring the old value at the end of the block. Ifitem
doesn’t exist onobj
, it will be created and then deleted at the end of the block.The old value (or
None
if it doesn’t exist) will be assigned to the target of the “as” clause, if there is one.
-
test.support.
print_warning
(msg)¶ Print a warning into
sys.__stderr__
. Format the message as:f"Warning -- {msg}"
. If msg is made of multiple lines, add"Warning -- "
prefix to each line.Novo na versão 3.9.
-
test.support.
wait_process
(pid, *, exitcode, timeout=None)¶ Wait until process pid completes and check that the process exit code is exitcode.
Raise an
AssertionError
if the process exit code is not equal to exitcode.If the process runs longer than timeout seconds (
SHORT_TIMEOUT
by default), kill the process and raise anAssertionError
. The timeout feature is not available on Windows.Novo na versão 3.9.
-
test.support.
calcobjsize
(fmt)¶ Return the size of the
PyObject
whose structure members are defined by fmt. The returned value includes the size of the Python object header and alignment.
-
test.support.
calcvobjsize
(fmt)¶ Return the size of the
PyVarObject
whose structure members are defined by fmt. The returned value includes the size of the Python object header and alignment.
-
test.support.
checksizeof
(test, o, size)¶ For testcase test, assert that the
sys.getsizeof
for o plus the GC header size equals size.
-
@
test.support.
anticipate_failure
(condition)¶ A decorator to conditionally mark tests with
unittest.expectedFailure()
. Any use of this decorator should have an associated comment identifying the relevant tracker issue.
-
test.support.
system_must_validate_cert
(f)¶ A decorator that skips the decorated test on TLS certification validation failures.
-
@
test.support.
run_with_locale
(catstr, *locales)¶ A decorator for running a function in a different locale, correctly resetting it after it has finished. catstr is the locale category as a string (for example
"LC_ALL"
). The locales passed will be tried sequentially, and the first valid locale will be used.
-
@
test.support.
run_with_tz
(tz)¶ A decorator for running a function in a specific timezone, correctly resetting it after it has finished.
-
@
test.support.
requires_freebsd_version
(*min_version)¶ Decorator for the minimum version when running test on FreeBSD. If the FreeBSD version is less than the minimum, the test is skipped.
-
@
test.support.
requires_linux_version
(*min_version)¶ Decorator for the minimum version when running test on Linux. If the Linux version is less than the minimum, the test is skipped.
-
@
test.support.
requires_mac_version
(*min_version)¶ Decorator for the minimum version when running test on macOS. If the macOS version is less than the minimum, the test is skipped.
-
@
test.support.
requires_IEEE_754
¶ Decorator for skipping tests on non-IEEE 754 platforms.
-
@
test.support.
requires_resource
(resource)¶ Decorator for skipping tests if resource is not available.
-
@
test.support.
requires_docstrings
¶ Decorator for only running the test if
HAVE_DOCSTRINGS
.
-
@
test.support.
cpython_only
¶ Decorator for tests only applicable to CPython.
-
@
test.support.
impl_detail
(msg=None, **guards)¶ Decorator for invoking
check_impl_detail()
on guards. If that returnsFalse
, then uses msg as the reason for skipping the test.
-
@
test.support.
no_tracing
¶ Decorator to temporarily turn off tracing for the duration of the test.
-
@
test.support.
refcount_test
¶ Decorator for tests which involve reference counting. The decorator does not run the test if it is not run by CPython. Any trace function is unset for the duration of the test to prevent unexpected refcounts caused by the trace function.
-
@
test.support.
bigmemtest
(size, memuse, dry_run=True)¶ Decorator for bigmem tests.
size is a requested size for the test (in arbitrary, test-interpreted units.) memuse is the number of bytes per unit for the test, or a good estimate of it. For example, a test that needs two byte buffers, of 4 GiB each, could be decorated with
@bigmemtest(size=_4G, memuse=2)
.The size argument is normally passed to the decorated test method as an extra argument. If dry_run is
True
, the value passed to the test method may be less than the requested value. If dry_run isFalse
, it means the test doesn’t support dummy runs when-M
is not specified.
-
@
test.support.
bigaddrspacetest
¶ Decorador para testes que preeenche o espaço do endereço.
-
test.support.
check_syntax_error
(testcase, statement, errtext='', *, lineno=None, offset=None)¶ Test for syntax errors in statement by attempting to compile statement. testcase is the
unittest
instance for the test. errtext is the regular expression which should match the string representation of the raisedSyntaxError
. If lineno is notNone
, compares to the line of the exception. If offset is notNone
, compares to the offset of the exception.
-
test.support.
open_urlresource
(url, *args, **kw)¶ Abre url. Se falhar em abrir, levanta
TestFailed
.
-
test.support.
reap_children
()¶ Use this at the end of
test_main
whenever sub-processes are started. This will help ensure that no extra children (zombies) stick around to hog resources and create problems when looking for refleaks.
-
test.support.
get_attribute
(obj, name)¶ Get an attribute, raising
unittest.SkipTest
ifAttributeError
is raised.
-
test.support.
catch_unraisable_exception
()¶ Context manager catching unraisable exception using
sys.unraisablehook()
.Storing the exception value (
cm.unraisable.exc_value
) creates a reference cycle. The reference cycle is broken explicitly when the context manager exits.Storing the object (
cm.unraisable.object
) can resurrect it if it is set to an object which is being finalized. Exiting the context manager clears the stored object.Uso:
with support.catch_unraisable_exception() as cm: # code creating an "unraisable exception" ... # check the unraisable exception: use cm.unraisable ... # cm.unraisable attribute no longer exists at this point # (to break a reference cycle)
Novo na versão 3.8.
-
test.support.
load_package_tests
(pkg_dir, loader, standard_tests, pattern)¶ Generic implementation of the
unittest
load_tests
protocol for use in test packages. pkg_dir is the root directory of the package; loader, standard_tests, and pattern are the arguments expected byload_tests
. In simple cases, the test package’s__init__.py
can be the following:import os from test.support import load_package_tests def load_tests(*args): return load_package_tests(os.path.dirname(__file__), *args)
-
test.support.
detect_api_mismatch
(ref_api, other_api, *, ignore=())¶ Returns the set of attributes, functions or methods of ref_api not found on other_api, except for a defined list of items to be ignored in this check specified in ignore.
By default this skips private attributes beginning with ‘_’ but includes all magic methods, i.e. those starting and ending in ‘__’.
Novo na versão 3.5.
-
test.support.
patch
(test_instance, object_to_patch, attr_name, new_value)¶ Override object_to_patch.attr_name with new_value. Also add cleanup procedure to test_instance to restore object_to_patch for attr_name. The attr_name should be a valid attribute for object_to_patch.
-
test.support.
run_in_subinterp
(code)¶ Run code in subinterpreter. Raise
unittest.SkipTest
iftracemalloc
is enabled.
-
test.support.
check_free_after_iterating
(test, iter, cls, args=())¶ Assert instances of cls are deallocated after iterating.
-
test.support.
missing_compiler_executable
(cmd_names=[])¶ Check for the existence of the compiler executables whose names are listed in cmd_names or all the compiler executables when cmd_names is empty and return the first missing executable or
None
when none is found missing.
-
test.support.
check__all__
(test_case, module, name_of_module=None, extra=(), not_exported=())¶ Assert that the
__all__
variable of module contains all public names.The module’s public names (its API) are detected automatically based on whether they match the public name convention and were defined in module.
The name_of_module argument can specify (as a string or tuple thereof) what module(s) an API could be defined in order to be detected as a public API. One case for this is when module imports part of its public API from other modules, possibly a C backend (like
csv
and its_csv
).The extra argument can be a set of names that wouldn’t otherwise be automatically detected as “public”, like objects without a proper
__module__
attribute. If provided, it will be added to the automatically detected ones.The not_exported argument can be a set of names that must not be treated as part of the public API even though their names indicate otherwise.
Exemplo de uso:
import bar import foo import unittest from test import support class MiscTestCase(unittest.TestCase): def test__all__(self): support.check__all__(self, foo) class OtherTestCase(unittest.TestCase): def test__all__(self): extra = {'BAR_CONST', 'FOO_CONST'} not_exported = {'baz'} # Undocumented name. # bar imports part of its API from _bar. support.check__all__(self, bar, ('bar', '_bar'), extra=extra, not_exported=not_exported)
Novo na versão 3.6.
-
test.support.
skip_if_broken_multiprocessing_synchronize
()¶ Skip tests if the
multiprocessing.synchronize
module is missing, if there is no available semaphore implementation, or if creating a lock raises anOSError
.Novo na versão 3.10.
-
test.support.
check_disallow_instantiation
(test_case, tp, *args, **kwds)¶ Assert that type tp cannot be instantiated using args and kwds.
Novo na versão 3.10.
-
test.support.
adjust_int_max_str_digits
(max_digits)¶ This function returns a context manager that will change the global
sys.set_int_max_str_digits()
setting for the duration of the context to allow execution of test code that needs a different limit on the number of digits when converting between an integer and string.Novo na versão 3.10.7.
The test.support
module defines the following classes:
-
class
test.support.
SuppressCrashReport
¶ A context manager used to try to prevent crash dialog popups on tests that are expected to crash a subprocess.
No Windows, desativa as caixas de diálogo Relatório de Erros do Windows usando SetErrorMode <https://msdn.microsoft.com/en-us/library/windows/desktop/ms680621.aspx>_.
On UNIX,
resource.setrlimit()
is used to setresource.RLIMIT_CORE
’s soft limit to 0 to prevent coredump file creation.On both platforms, the old value is restored by
__exit__()
.
-
class
test.support.
SaveSignals
¶ Class to save and restore signal handlers registered by the Python signal handler.
-
save
(self)¶ Save the signal handlers to a dictionary mapping signal numbers to the current signal handler.
-
test.support.socket_helper
— Utilities for socket tests¶
The test.support.socket_helper
module provides support for socket tests.
Novo na versão 3.9.
-
test.support.socket_helper.
IPV6_ENABLED
¶ Set to
True
if IPv6 is enabled on this host,False
otherwise.
-
test.support.socket_helper.
find_unused_port
(family=socket.AF_INET, socktype=socket.SOCK_STREAM)¶ Returns an unused port that should be suitable for binding. This is achieved by creating a temporary socket with the same family and type as the
sock
parameter (default isAF_INET
,SOCK_STREAM
), and binding it to the specified host address (defaults to0.0.0.0
) with the port set to 0, eliciting an unused ephemeral port from the OS. The temporary socket is then closed and deleted, and the ephemeral port is returned.Either this method or
bind_port()
should be used for any tests where a server socket needs to be bound to a particular port for the duration of the test. Which one to use depends on whether the calling code is creating a Python socket, or if an unused port needs to be provided in a constructor or passed to an external program (i.e. the-accept
argument to openssl’s s_server mode). Always preferbind_port()
overfind_unused_port()
where possible. Using a hard coded port is discouraged since it can make multiple instances of the test impossible to run simultaneously, which is a problem for buildbots.
-
test.support.socket_helper.
bind_port
(sock, host=HOST)¶ Bind the socket to a free port and return the port number. Relies on ephemeral ports in order to ensure we are using an unbound port. This is important as many tests may be running simultaneously, especially in a buildbot environment. This method raises an exception if the
sock.family
isAF_INET
andsock.type
isSOCK_STREAM
, and the socket hasSO_REUSEADDR
orSO_REUSEPORT
set on it. Tests should never set these socket options for TCP/IP sockets. The only case for setting these options is testing multicasting via multiple UDP sockets.Additionally, if the
SO_EXCLUSIVEADDRUSE
socket option is available (i.e. on Windows), it will be set on the socket. This will prevent anyone else from binding to our host/port for the duration of the test.
-
test.support.socket_helper.
bind_unix_socket
(sock, addr)¶ Bind a Unix socket, raising
unittest.SkipTest
ifPermissionError
is raised.
-
@
test.support.socket_helper.
skip_unless_bind_unix_socket
¶ A decorator for running tests that require a functional
bind()
for Unix sockets.
-
test.support.socket_helper.
transient_internet
(resource_name, *, timeout=30.0, errnos=())¶ A context manager that raises
ResourceDenied
when various issues with the internet connection manifest themselves as exceptions.
test.support.script_helper
— Utilities for the Python execution tests¶
The test.support.script_helper
module provides support for Python’s
script execution tests.
-
test.support.script_helper.
interpreter_requires_environment
()¶ Return
True
ifsys.executable interpreter
requires environment variables in order to be able to run at all.This is designed to be used with
@unittest.skipIf()
to annotate tests that need to use anassert_python*()
function to launch an isolated mode (-I
) or no environment mode (-E
) sub-interpreter process.A normal build & test does not run into this situation but it can happen when trying to run the standard library test suite from an interpreter that doesn’t have an obvious home with Python’s current home finding logic.
Setting
PYTHONHOME
is one way to get most of the testsuite to run in that situation.PYTHONPATH
orPYTHONUSERSITE
are other common environment variables that might impact whether or not the interpreter can start.
-
test.support.script_helper.
run_python_until_end
(*args, **env_vars)¶ Set up the environment based on env_vars for running the interpreter in a subprocess. The values can include
__isolated
,__cleanenv
,__cwd
, andTERM
.Alterado na versão 3.9: The function no longer strips whitespaces from stderr.
-
test.support.script_helper.
assert_python_ok
(*args, **env_vars)¶ Assert that running the interpreter with args and optional environment variables env_vars succeeds (
rc == 0
) and return a(return code, stdout, stderr)
tuple.If the __cleanenv keyword-only parameter is set, env_vars is used as a fresh environment.
Python is started in isolated mode (command line option
-I
), except if the __isolated keyword-only parameter is set toFalse
.Alterado na versão 3.9: The function no longer strips whitespaces from stderr.
-
test.support.script_helper.
assert_python_failure
(*args, **env_vars)¶ Assert that running the interpreter with args and optional environment variables env_vars fails (
rc != 0
) and return a(return code, stdout, stderr)
tuple.See
assert_python_ok()
for more options.Alterado na versão 3.9: The function no longer strips whitespaces from stderr.
-
test.support.script_helper.
spawn_python
(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, **kw)¶ Run a Python subprocess with the given arguments.
kw is extra keyword args to pass to
subprocess.Popen()
. Returns asubprocess.Popen
object.
-
test.support.script_helper.
kill_python
(p)¶ Run the given
subprocess.Popen
process until completion and return stdout.
-
test.support.script_helper.
make_script
(script_dir, script_basename, source, omit_suffix=False)¶ Cria um script contendo source no caminho script_dir e script_basename. Se omit_suffix
False
, acrescente.py
ao nome. Retorna o caminho completo do script.
-
test.support.script_helper.
make_zip_script
(zip_dir, zip_basename, script_name, name_in_zip=None)¶ Cria um arquivo zip em zip_dir e zip_basename com a extensão
zip
que contém os arquivos em script_name. name_in_zip é o nome do arquivo. Retorna uma tupla contendo(full path, full path of archive name)
.
-
test.support.script_helper.
make_pkg
(pkg_dir, init_source='')¶ Cria um diretório nomeado pkg_dir contendo um arquivo
__init__
com init_source como seus conteúdos.
-
test.support.script_helper.
make_zip_pkg
(zip_dir, zip_basename, pkg_name, script_basename, source, depth=1, compiled=False)¶ Create a zip package directory with a path of zip_dir and zip_basename containing an empty
__init__
file and a file script_basename containing the source. If compiled isTrue
, both source files will be compiled and added to the zip package. Return a tuple of the full zip path and the archive name for the zip file.
test.support.bytecode_helper
— Ferramentas de suporte para testar a geração correta de bytecode¶
The test.support.bytecode_helper
module provides support for testing
and inspecting bytecode generation.
Novo na versão 3.9.
O módulo define a seguinte classe:
-
class
test.support.bytecode_helper.
BytecodeTestCase
(unittest.TestCase)¶ This class has custom assertion methods for inspecting bytecode.
-
BytecodeTestCase.
get_disassembly_as_string
(co)¶ Return the disassembly of co as string.
-
BytecodeTestCase.
assertInBytecode
(x, opname, argval=_UNSPECIFIED)¶ Return instr if opname is found, otherwise throws
AssertionError
.
-
BytecodeTestCase.
assertNotInBytecode
(x, opname, argval=_UNSPECIFIED)¶ Throws
AssertionError
if opname is found.
test.support.threading_helper
— Utilities for threading tests¶
The test.support.threading_helper
module provides support for threading tests.
Novo na versão 3.10.
-
test.support.threading_helper.
join_thread
(thread, timeout=None)¶ Join a thread within timeout. Raise an
AssertionError
if thread is still alive after timeout seconds.
-
@
test.support.threading_helper.
reap_threads
¶ Decorator to ensure the threads are cleaned up even if the test fails.
-
test.support.threading_helper.
start_threads
(threads, unlock=None)¶ Context manager to start threads, which is a sequence of threads. unlock is a function called after the threads are started, even if an exception was raised; an example would be
threading.Event.set()
.start_threads
will attempt to join the started threads upon exit.
-
test.support.threading_helper.
threading_cleanup
(*original_values)¶ Cleanup up threads not specified in original_values. Designed to emit a warning if a test leaves running threads in the background.
-
test.support.threading_helper.
threading_setup
()¶ Return current thread count and copy of dangling threads.
-
test.support.threading_helper.
wait_threads_exit
(timeout=None)¶ Context manager to wait until all threads created in the
with
statement exit.
-
test.support.threading_helper.
catch_threading_exception
()¶ Context manager catching
threading.Thread
exception usingthreading.excepthook()
.Attributes set when an exception is caught:
exc_type
exc_value
exc_traceback
thread
See
threading.excepthook()
documentation.These attributes are deleted at the context manager exit.
Uso:
with threading_helper.catch_threading_exception() as cm: # code spawning a thread which raises an exception ... # check the thread exception, use cm attributes: # exc_type, exc_value, exc_traceback, thread ... # exc_type, exc_value, exc_traceback, thread attributes of cm no longer # exists at this point # (to avoid reference cycles)
Novo na versão 3.8.
test.support.os_helper
— Utilities for os tests¶
The test.support.os_helper
module provides support for os tests.
Novo na versão 3.10.
-
test.support.os_helper.
FS_NONASCII
¶ A non-ASCII character encodable by
os.fsencode()
.
-
test.support.os_helper.
SAVEDCWD
¶ Set to
os.getcwd()
.
-
test.support.os_helper.
TESTFN
¶ Set to a name that is safe to use as the name of a temporary file. Any temporary file that is created should be closed and unlinked (removed).
-
test.support.os_helper.
TESTFN_NONASCII
¶ Set to a filename containing the
FS_NONASCII
character, if it exists. This guarantees that if the filename exists, it can be encoded and decoded with the default filesystem encoding. This allows tests that require a non-ASCII filename to be easily skipped on platforms where they can’t work.
-
test.support.os_helper.
TESTFN_UNENCODABLE
¶ Define o nome de arquivo (tipo str) que não pode ser codificado pela codificação do sistema de arquivos no modo estrito. Ele pode ser
None
se não for possível gerar como um nome de arquivo.
-
test.support.os_helper.
TESTFN_UNDECODABLE
¶ Define o nome de arquivo (tipo str) que não pode ser codificado pela codificação do sistema de arquivos no modo estrito. Ele pode ser
None
se não for possível ser gerado com um nome de arquivo.
-
test.support.os_helper.
TESTFN_UNICODE
¶ Define um nome não-ASCII para o arquivo temporário.
-
class
test.support.os_helper.
EnvironmentVarGuard
¶ Class used to temporarily set or unset environment variables. Instances can be used as a context manager and have a complete dictionary interface for querying/modifying the underlying
os.environ
. After exit from the context manager all changes to environment variables done through this instance will be rolled back.Alterado na versão 3.1: Adicionada uma interface para dicionário.
-
class
test.support.os_helper.
FakePath
(path)¶ Simple path-like object. It implements the
__fspath__()
method which just returns the path argument. If path is an exception, it will be raised in__fspath__()
.
-
EnvironmentVarGuard.
set
(envvar, value)¶ Temporariamente define a variável de ambiente
envvar
para o valorvalue
.
-
EnvironmentVarGuard.
unset
(envvar)¶ Desativa temporariamente a variável de ambiente
envvar
.
-
test.support.os_helper.
can_symlink
()¶ Return
True
if the OS supports symbolic links,False
otherwise.
-
test.support.os_helper.
can_xattr
()¶ Return
True
if the OS supports xattr,False
otherwise.
-
test.support.os_helper.
change_cwd
(path, quiet=False)¶ A context manager that temporarily changes the current working directory to path and yields the directory.
If quiet is
False
, the context manager raises an exception on error. Otherwise, it issues only a warning and keeps the current working directory the same.
-
test.support.os_helper.
create_empty_file
(filename)¶ Create an empty file with filename. If it already exists, truncate it.
-
test.support.os_helper.
fd_count
()¶ Conta o número de descritores de arquivos abertos.
-
test.support.os_helper.
fs_is_case_insensitive
(directory)¶ Return
True
if the file system for directory is case-insensitive.
-
test.support.os_helper.
make_bad_fd
()¶ Cria um descritor de arquivo inválido abrindo e fechando um arquivo temporário e retornando seu descritor.
-
test.support.os_helper.
rmdir
(filename)¶ Call
os.rmdir()
on filename. On Windows platforms, this is wrapped with a wait loop that checks for the existence of the file, which is needed due to antivirus programs that can hold files open and prevent deletion.
-
test.support.os_helper.
rmtree
(path)¶ Call
shutil.rmtree()
on path or callos.lstat()
andos.rmdir()
to remove a path and its contents. As withrmdir()
, on Windows platforms this is wrapped with a wait loop that checks for the existence of the files.
-
@
test.support.os_helper.
skip_unless_symlink
¶ Um decorador para executar testes que requerem suporte para links simbólicos.
-
@
test.support.os_helper.
skip_unless_xattr
¶ Um decorador para execução de testes que requerem suporte para xattr.
-
test.support.os_helper.
temp_cwd
(name='tempcwd', quiet=False)¶ Um gerenciador de contexto que cria temporariamente um novo diretório e altera o diretório de trabalho atual (CWD).
The context manager creates a temporary directory in the current directory with name name before temporarily changing the current working directory. If name is
None
, the temporary directory is created usingtempfile.mkdtemp()
.Se quiet é
False
e ele não possibilita criar ou alterar o CWD, um erro é levantado. Por outro lado, somente um aviso surge e o CWD original é utilizado.
-
test.support.os_helper.
temp_dir
(path=None, quiet=False)¶ Um gerenciador de contexto que cria um diretório temporário no path e produz o diretório.
If path is
None
, the temporary directory is created usingtempfile.mkdtemp()
. If quiet isFalse
, the context manager raises an exception on error. Otherwise, if path is specified and cannot be created, only a warning is issued.
-
test.support.os_helper.
temp_umask
(umask)¶ Um gerenciador de contexto que temporariamente define o umask do processo.
-
test.support.os_helper.
unlink
(filename)¶ Call
os.unlink()
on filename. As withrmdir()
, on Windows platforms, this is wrapped with a wait loop that checks for the existence of the file.
test.support.import_helper
— Utilities for import tests¶
The test.support.import_helper
module provides support for import tests.
Novo na versão 3.10.
-
test.support.import_helper.
forget
(module_name)¶ Remove the module named module_name from
sys.modules
and delete any byte-compiled files of the module.
-
test.support.import_helper.
import_fresh_module
(name, fresh=(), blocked=(), deprecated=False)¶ This function imports and returns a fresh copy of the named Python module by removing the named module from
sys.modules
before doing the import. Note that unlikereload()
, the original module is not affected by this operation.fresh is an iterable of additional module names that are also removed from the
sys.modules
cache before doing the import.blocked is an iterable of module names that are replaced with
None
in the module cache during the import to ensure that attempts to import them raiseImportError
.The named module and any modules named in the fresh and blocked parameters are saved before starting the import and then reinserted into
sys.modules
when the fresh import is complete.Module and package deprecation messages are suppressed during this import if deprecated is
True
.This function will raise
ImportError
if the named module cannot be imported.Exemplo de uso:
# Get copies of the warnings module for testing without affecting the # version being used by the rest of the test suite. One copy uses the # C implementation, the other is forced to use the pure Python fallback # implementation py_warnings = import_fresh_module('warnings', blocked=['_warnings']) c_warnings = import_fresh_module('warnings', fresh=['_warnings'])
Novo na versão 3.1.
-
test.support.import_helper.
import_module
(name, deprecated=False, *, required_on=())¶ This function imports and returns the named module. Unlike a normal import, this function raises
unittest.SkipTest
if the module cannot be imported.Module and package deprecation messages are suppressed during this import if deprecated is
True
. If a module is required on a platform but optional for others, set required_on to an iterable of platform prefixes which will be compared againstsys.platform
.Novo na versão 3.1.
-
test.support.import_helper.
modules_setup
()¶ Retorna a cópia de
sys.modules
.
-
test.support.import_helper.
modules_cleanup
(oldmodules)¶ Remove modules except for oldmodules and
encodings
in order to preserve internal cache.
-
test.support.import_helper.
unload
(name)¶ Exclui o name de
sys.modules
.
-
test.support.import_helper.
make_legacy_pyc
(source)¶ Move a PEP 3147/PEP 488 pyc file to its legacy pyc location and return the file system path to the legacy pyc file. The source value is the file system path to the source file. It does not need to exist, however the PEP 3147/488 pyc file must exist.
-
class
test.support.import_helper.
CleanImport
(*module_names)¶ A context manager to force import to return a new module reference. This is useful for testing module-level behaviors, such as the emission of a
DeprecationWarning
on import. Example usage:with CleanImport('foo'): importlib.import_module('foo') # New reference.
-
class
test.support.import_helper.
DirsOnSysPath
(*paths)¶ A context manager to temporarily add directories to
sys.path
.This makes a copy of
sys.path
, appends any directories given as positional arguments, then revertssys.path
to the copied settings when the context ends.Note that all
sys.path
modifications in the body of the context manager, including replacement of the object, will be reverted at the end of the block.
test.support.warnings_helper
— Utilities for warnings tests¶
The test.support.warnings_helper
module provides support for warnings tests.
Novo na versão 3.10.
-
test.support.warnings_helper.
ignore_warnings
(*, category)¶ Suppress warnings that are instances of category, which must be
Warning
or a subclass. Roughly equivalent towarnings.catch_warnings()
withwarnings.simplefilter('ignore', category=category)
. For example:@warning_helper.ignore_warnings(category=DeprecationWarning) def test_suppress_warning(): # do something
Novo na versão 3.8.
-
test.support.warnings_helper.
check_no_resource_warning
(testcase)¶ Context manager to check that no
ResourceWarning
was raised. You must remove the object which may emitResourceWarning
before the end of the context manager.
-
test.support.warnings_helper.
check_syntax_warning
(testcase, statement, errtext='', *, lineno=1, offset=None)¶ Test for syntax warning in statement by attempting to compile statement. Test also that the
SyntaxWarning
is emitted only once, and that it will be converted to aSyntaxError
when turned into error. testcase is theunittest
instance for the test. errtext is the regular expression which should match the string representation of the emittedSyntaxWarning
and raisedSyntaxError
. If lineno is notNone
, compares to the line of the warning and exception. If offset is notNone
, compares to the offset of the exception.Novo na versão 3.8.
-
test.support.warnings_helper.
check_warnings
(*filters, quiet=True)¶ A convenience wrapper for
warnings.catch_warnings()
that makes it easier to test that a warning was correctly raised. It is approximately equivalent to callingwarnings.catch_warnings(record=True)
withwarnings.simplefilter()
set toalways
and with the option to automatically validate the results that are recorded.check_warnings
accepts 2-tuples of the form("message regexp", WarningCategory)
as positional arguments. If one or more filters are provided, or if the optional keyword argument quiet isFalse
, it checks to make sure the warnings are as expected: each specified filter must match at least one of the warnings raised by the enclosed code or the test fails, and if any warnings are raised that do not match any of the specified filters the test fails. To disable the first of these checks, set quiet toTrue
.Se nenhum argumento é especificado, o padrão é:
check_warnings(("", Warning), quiet=True)
Nesse caso, todos os avisos são capturados e nenhum erro é gerado.
On entry to the context manager, a
WarningRecorder
instance is returned. The underlying warnings list fromcatch_warnings()
is available via the recorder object’swarnings
attribute. As a convenience, the attributes of the object representing the most recent warning can also be accessed directly through the recorder object (see example below). If no warning has been raised, then any of the attributes that would otherwise be expected on an object representing a warning will returnNone
.The recorder object also has a
reset()
method, which clears the warnings list.O gerenciador de contexto é desenhado para ser utilizado dessa forma:
with check_warnings(("assertion is always true", SyntaxWarning), ("", UserWarning)): exec('assert(False, "Hey!")') warnings.warn(UserWarning("Hide me!"))
No caso, se um aviso não foi levantado, ou algum outro aviso não foi levantado,
check_warnings()
deveria aparecer como um erro.When a test needs to look more deeply into the warnings, rather than just checking whether or not they occurred, code like this can be used:
with check_warnings(quiet=True) as w: warnings.warn("foo") assert str(w.args[0]) == "foo" warnings.warn("bar") assert str(w.args[0]) == "bar" assert str(w.warnings[0].args[0]) == "foo" assert str(w.warnings[1].args[0]) == "bar" w.reset() assert len(w.warnings) == 0
Aqui todos os avisos serão capturados e o código de teste testa os avisos diretamente capturados.
Alterado na versão 3.2: Novos argumentos opcionais filters e quiet.
-
class
test.support.warnings_helper.
WarningsRecorder
¶ Class used to record warnings for unit tests. See documentation of
check_warnings()
above for more details.