Python warnings.html() Examples

def deprecation(message, stacklevel=None, category=None):
    """Warns about some type of deprecation that has been (or will be) made.

    This helper function makes it easier to interact with the warnings module
    by standardizing the arguments that the warning function receives so that
    it is easier to use.

    This should be used to emit warnings to users (users can easily turn these
    warnings off/on, see https://docs.python.org/2/library/warnings.html
    as they see fit so that the messages do not fill up the users logs with
    warnings that they do not wish to see in production) about functions,
    methods, attributes or other code that is deprecated and will be removed
    in a future release (this is done using these warnings to avoid breaking
    existing users of those functions, methods, code; which a library should
    avoid doing by always giving at *least* N + 1 release for users to address
    the deprecation warnings).
    """
    if not _enabled:
        return
    if category is None:
        category = DeprecationWarning
    if stacklevel is None:
        warnings.warn(message, category=category)
    else:
        warnings.warn(message, category=category, stacklevel=stacklevel) 

def _filter_deprecation_warnings():
    """Apply filters to deprecation warnings.

    Force the `DeprecationWarning` warnings to be displayed for the qiskit
    module, overriding the system configuration as they are ignored by default
    [1] for end-users. Additionally, silence the `ChangedInMarshmallow3Warning`
    messages.

    TODO: on Python 3.7, this might not be needed due to PEP-0565 [2].

    [1] https://docs.python.org/3/library/warnings.html#default-warning-filters
    [2] https://www.python.org/dev/peps/pep-0565/
    """
    deprecation_filter = ('always', None, DeprecationWarning,
                          re.compile(r'^qiskit\.*', re.UNICODE), 0)

    # Instead of using warnings.simple_filter() directly, the internal
    # _add_filter() function is used for being able to match against the
    # module.
    try:
        warnings._add_filter(*deprecation_filter, append=False)
    except AttributeError:
        # ._add_filter is internal and not available in some Python versions.
        pass 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Integer: self.__class__,
                Interval: DateTime,
                Time: DateTime,
            },
            operators.sub: {
                # date - integer = date
                Integer: self.__class__,

                # date - date = integer.
                Date: Integer,

                Interval: DateTime,

                # date - datetime = interval,
                # this one is not in the PG docs
                # but works
                DateTime: Interval,
            },
        } 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Date: DateTime,
                Interval: self.__class__,
                DateTime: DateTime,
                Time: Time,
            },
            operators.sub: {
                Interval: self.__class__
            },
            operators.mul: {
                Numeric: self.__class__
            },
            operators.truediv: {
                Numeric: self.__class__
            },
            operators.div: {
                Numeric: self.__class__
            }
        } 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Integer: self.__class__,
                Interval: DateTime,
                Time: DateTime,
            },
            operators.sub: {
                # date - integer = date
                Integer: self.__class__,
                # date - date = integer.
                Date: Integer,
                Interval: DateTime,
                # date - datetime = interval,
                # this one is not in the PG docs
                # but works
                DateTime: Interval,
            },
        } 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Date: DateTime,
                Interval: self.__class__,
                DateTime: DateTime,
                Time: Time,
            },
            operators.sub: {Interval: self.__class__},
            operators.mul: {Numeric: self.__class__},
            operators.truediv: {Numeric: self.__class__},
            operators.div: {Numeric: self.__class__},
        } 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Integer: self.__class__,
                Interval: DateTime,
                Time: DateTime,
            },
            operators.sub: {
                # date - integer = date
                Integer: self.__class__,

                # date - date = integer.
                Date: Integer,

                Interval: DateTime,

                # date - datetime = interval,
                # this one is not in the PG docs
                # but works
                DateTime: Interval,
            },
        } 

def _expression_adaptations(self):
        # Based on http://www.postgresql.org/docs/current/\
        # static/functions-datetime.html.

        return {
            operators.add: {
                Date: DateTime,
                Interval: self.__class__,
                DateTime: DateTime,
                Time: Time,
            },
            operators.sub: {
                Interval: self.__class__
            },
            operators.mul: {
                Numeric: self.__class__
            },
            operators.truediv: {
                Numeric: self.__class__
            },
            operators.div: {
                Numeric: self.__class__
            }
        } 

def pytest_configure(config):
    config.addinivalue_line(
        "markers",
        "filterwarnings(warning): add a warning filter to the given test. "
        "see https://docs.pytest.org/en/latest/warnings.html#pytest-mark-filterwarnings ",
    ) 

def recwarn():
    """Return a :class:`WarningsRecorder` instance that records all warnings emitted by test functions.

    See http://docs.python.org/library/warnings.html for information
    on warning categories.
    """
    wrec = WarningsRecorder()
    with wrec:
        warnings.simplefilter("default")
        yield wrec 

def pytest_configure(config):
    config.addinivalue_line(
        "markers",
        "filterwarnings(warning): add a warning filter to the given test. "
        "see https://docs.pytest.org/en/latest/warnings.html#pytest-mark-filterwarnings ",
    ) 

def recwarn():
    """Return a :class:`WarningsRecorder` instance that records all warnings emitted by test functions.

    See http://docs.python.org/library/warnings.html for information
    on warning categories.
    """
    wrec = WarningsRecorder()
    with wrec:
        warnings.simplefilter("default")
        yield wrec 

def test_deprecated():
    # Test whether the deprecated decorator issues appropriate warnings
    # Copied almost verbatim from https://docs.python.org/library/warnings.html

    # First a function...
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always")

        @deprecated()
        def ham():
            return "spam"

        spam = ham()

        assert_equal(spam, "spam")     # function must remain usable

        assert_equal(len(w), 1)
        assert issubclass(w[0].category, DeprecationWarning)
        assert "deprecated" in str(w[0].message).lower()

    # ... then a class.
    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always")

        @deprecated("don't use this")
        class Ham:
            SPAM = 1

        ham = Ham()

        assert hasattr(ham, "SPAM")

        assert_equal(len(w), 1)
        assert issubclass(w[0].category, DeprecationWarning)
        assert "deprecated" in str(w[0].message).lower() 

def group(s, n):
    # See http://www.python.org/doc/2.6/library/functions.html#zip
    return zip(*[iter(s)]*n) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of
    data from each pixel in `ipixels` followed by the `apsize` elements
    of data from each pixel in `apixels`.  Conventionally `ipixels`
    and `apixels` are byte arrays so the sizes are bytes, but it
    actually works with any arrays of the same type.  The returned
    array is the same type as the input arrays which should be the
    same type as each other.
    """

    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i+ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def isinteger(x):
    try:
        return int(x) == x
    except (TypeError, ValueError):
        return False


# === Legacy Version Support ===

# :pyver:old:  PyPNG works on Python versions 2.3 and 2.2, but not
# without some awkward problems.  Really PyPNG works on Python 2.4 (and
# above); it works on Pythons 2.3 and 2.2 by virtue of fixing up
# problems here.  It's a bit ugly (which is why it's hidden down here).
#
# Generally the strategy is one of pretending that we're running on
# Python 2.4 (or above), and patching up the library support on earlier
# versions so that it looks enough like Python 2.4.  When it comes to
# Python 2.2 there is one thing we cannot patch: extended slices
# http://www.python.org/doc/2.3/whatsnew/section-slices.html.
# Instead we simply declare that features that are implemented using
# extended slices will not work on Python 2.2.
#
# In order to work on Python 2.3 we fix up a recurring annoyance involving
# the array type.  In Python 2.3 an array cannot be initialised with an
# array, and it cannot be extended with a list (or other sequence).
# Both of those are repeated issues in the code.  Whilst I would not
# normally tolerate this sort of behaviour, here we "shim" a replacement
# for array into place (and hope no-one notices).  You never read this.
#
# In an amusing case of warty hacks on top of warty hacks... the array
# shimming we try and do only works on Python 2.3 and above (you can't
# subclass array.array in Python 2.2).  So to get it working on Python
# 2.2 we go for something much simpler and (probably) way slower. 

def group(s, n):
    # See http://www.python.org/doc/2.6/library/functions.html#zip
    return list(zip(*[iter(s)]*n)) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of
    data from each pixel in `ipixels` followed by the `apsize` elements
    of data from each pixel in `apixels`.  Conventionally `ipixels`
    and `apixels` are byte arrays so the sizes are bytes, but it
    actually works with any arrays of the same type.  The returned
    array is the same type as the input arrays which should be the
    same type as each other.
    """

    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i+ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def group(s, n):
    """Repack iterator items into groups"""
    # See http://www.python.org/doc/2.6/library/functions.html#zip
    return list(zip(*[iter(s)] * n)) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of
    data from each pixel in `ipixels` followed by the `apsize` elements
    of data from each pixel in `apixels`.  Conventionally `ipixels`
    and `apixels` are byte arrays so the sizes are bytes, but it
    actually works with any arrays of the same type.  The returned
    array is the same type as the input arrays which should be the
    same type as each other.
    """
    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i + ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def pytest_configure(config: Config) -> None:
    config.addinivalue_line(
        "markers",
        "filterwarnings(warning): add a warning filter to the given test. "
        "see https://docs.pytest.org/en/latest/warnings.html#pytest-mark-filterwarnings ",
    ) 

def recwarn() -> Generator["WarningsRecorder", None, None]:
    """Return a :class:`WarningsRecorder` instance that records all warnings emitted by test functions.

    See http://docs.python.org/library/warnings.html for information
    on warning categories.
    """
    wrec = WarningsRecorder()
    with wrec:
        warnings.simplefilter("default")
        yield wrec 

def group(s, n):
    # See http://www.python.org/doc/2.6/library/functions.html#zip
    return list(zip(*[iter(s)]*n)) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of
    data from each pixel in `ipixels` followed by the `apsize` elements
    of data from each pixel in `apixels`.  Conventionally `ipixels`
    and `apixels` are byte arrays so the sizes are bytes, but it
    actually works with any arrays of the same type.  The returned
    array is the same type as the input arrays which should be the
    same type as each other.
    """

    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i+ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def group(s, n):
    # See http://www.python.org/doc/2.6/library/functions.html#zip
    return zip(*[iter(s)]*n) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of
    data from each pixel in `ipixels` followed by the `apsize` elements
    of data from each pixel in `apixels`.  Conventionally `ipixels`
    and `apixels` are byte arrays so the sizes are bytes, but it
    actually works with any arrays of the same type.  The returned
    array is the same type as the input arrays which should be the
    same type as each other.
    """

    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i+ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def isinteger(x):
    try:
        return int(x) == x
    except (TypeError, ValueError):
        return False


# === Legacy Version Support ===

# :pyver:old:  PyPNG works on Python versions 2.3 and 2.2, but not
# without some awkward problems.  Really PyPNG works on Python 2.4 (and
# above); it works on Pythons 2.3 and 2.2 by virtue of fixing up
# problems here.  It's a bit ugly (which is why it's hidden down here).
#
# Generally the strategy is one of pretending that we're running on
# Python 2.4 (or above), and patching up the library support on earlier
# versions so that it looks enough like Python 2.4.  When it comes to
# Python 2.2 there is one thing we cannot patch: extended slices
# http://www.python.org/doc/2.3/whatsnew/section-slices.html.
# Instead we simply declare that features that are implemented using
# extended slices will not work on Python 2.2.
#
# In order to work on Python 2.3 we fix up a recurring annoyance involving
# the array type.  In Python 2.3 an array cannot be initialised with an
# array, and it cannot be extended with a list (or other sequence).
# Both of those are repeated issues in the code.  Whilst I would not
# normally tolerate this sort of behaviour, here we "shim" a replacement
# for array into place (and hope no-one notices).  You never read this.
#
# In an amusing case of warty hacks on top of warty hacks... the array
# shimming we try and do only works on Python 2.3 and above (you can't
# subclass array.array in Python 2.2).  So to get it working on Python
# 2.2 we go for something much simpler and (probably) way slower. 

def group(s, n):
    # See
    # http://www.python.org/doc/2.6/library/functions.html#zip
    return zip(*[iter(s)]*n) 

def interleave_planes(ipixels, apixels, ipsize, apsize):
    """
    Interleave (colour) planes, e.g. RGB + A = RGBA.

    Return an array of pixels consisting of the `ipsize` elements of data
    from each pixel in `ipixels` followed by the `apsize` elements of data
    from each pixel in `apixels`.  Conventionally `ipixels` and
    `apixels` are byte arrays so the sizes are bytes, but it actually
    works with any arrays of the same type.  The returned array is the
    same type as the input arrays which should be the same type as each other.
    """

    itotal = len(ipixels)
    atotal = len(apixels)
    newtotal = itotal + atotal
    newpsize = ipsize + apsize
    # Set up the output buffer
    # See http://www.python.org/doc/2.4.4/lib/module-array.html#l2h-1356
    out = array(ipixels.typecode)
    # It's annoying that there is no cheap way to set the array size :-(
    out.extend(ipixels)
    out.extend(apixels)
    # Interleave in the pixel data
    for i in range(ipsize):
        out[i:newtotal:newpsize] = ipixels[i:itotal:ipsize]
    for i in range(apsize):
        out[i+ipsize:newtotal:newpsize] = apixels[i:atotal:apsize]
    return out 

def mycallersname():
    """Returns the name of the caller of the caller of this function
    (hence the name of the caller of the function in which
    "mycallersname()" textually appears).  Returns None if this cannot
    be determined."""

    # http://docs.python.org/library/inspect.html#the-interpreter-stack
    import inspect

    frame = inspect.currentframe()
    if not frame:
        return None
    frame_,filename_,lineno_,funname,linelist_,listi_ = (
      inspect.getouterframes(frame)[2])
    return funname