Lib/test/test_doctest.py

"""
Test script for doctest.
"""

from test import test_support
import doctest

######################################################################
## Sample Objects (used by test cases)
######################################################################

def sample_func(v):
    """
    >>> print sample_func(22)
    44
    """
    return v+v

class SampleClass:
    """
    >>> print 1
    1
    """
    def __init__(self, val):
        """
        >>> print SampleClass(12).get()
        12
        """
        self.val = val

    def double(self):
        """
        >>> print SampleClass(12).double().get()
        24
        """
        return SampleClass(self.val + self.val)

    def get(self):
        """
        >>> print SampleClass(-5).get()
        -5
        """
        return self.val

    def a_staticmethod(v):
        """
        >>> print SampleClass.a_staticmethod(10)
        11
        """
        return v+1
    a_staticmethod = staticmethod(a_staticmethod)

    def a_classmethod(cls, v):
        """
        >>> print SampleClass.a_classmethod(10)
        12
        >>> print SampleClass(0).a_classmethod(10)
        12
        """
        return v+2
    a_classmethod = classmethod(a_classmethod)

    a_property = property(get, doc="""
        >>> print SampleClass(22).a_property
        22
        """)

    class NestedClass:
        """
        >>> x = SampleClass.NestedClass(5)
        >>> y = x.square()
        >>> print y.get()
        25
        """
        def __init__(self, val=0):
            """
            >>> print SampleClass.NestedClass().get()
            0
            """
            self.val = val
        def square(self):
            return SampleClass.NestedClass(self.val*self.val)
        def get(self):
            return self.val

class SampleNewStyleClass(object):
    r"""
    >>> print '1\n2\n3'
    1
    2
    3
    """
    def __init__(self, val):
        """
        >>> print SampleNewStyleClass(12).get()
        12
        """
        self.val = val

    def double(self):
        """
        >>> print SampleNewStyleClass(12).double().get()
        24
        """
        return SampleNewStyleClass(self.val + self.val)

    def get(self):
        """
        >>> print SampleNewStyleClass(-5).get()
        -5
        """
        return self.val

######################################################################
## Test Cases
######################################################################

def test_Example(): r"""
Unit tests for the `Example` class.

Example is a simple container class that holds a source code string,
an expected output string, and a line number (within the docstring):

    >>> example = doctest.Example('print 1', '1\n', 0)
    >>> (example.source, example.want, example.lineno)
    ('print 1', '1\n', 0)

The `source` string should end in a newline iff the source spans more
than one line:

    >>> # Source spans a single line: no terminating newline.
    >>> e = doctest.Example('print 1', '1\n', 0)
    >>> e = doctest.Example('print 1\n', '1\n', 0)
    Traceback (most recent call last):
    AssertionError

    >>> # Source spans multiple lines: require terminating newline.
    >>> e = doctest.Example('print 1;\nprint 2\n', '1\n2\n', 0)
    >>> e = doctest.Example('print 1;\nprint 2', '1\n2\n', 0)
    Traceback (most recent call last):
    AssertionError

The `want` string should be terminated by a newline, unless it's the
empty string:

    >>> e = doctest.Example('print 1', '1\n', 0)
    >>> e = doctest.Example('print 1', '1', 0)
    Traceback (most recent call last):
    AssertionError
    >>> e = doctest.Example('print', '', 0)
"""

def test_DocTest(): r"""
Unit tests for the `DocTest` class.

DocTest is a collection of examples, extracted from a docstring, along
with information about where the docstring comes from (a name,
filename, and line number).  The docstring is parsed by the `DocTest`
constructor:

    >>> docstring = '''
    ...     >>> print 12
    ...     12
    ...
    ... Non-example text.
    ...
    ...     >>> print 'another\example'
    ...     another
    ...     example
    ... '''
    >>> globs = {} # globals to run the test in.
    >>> test = doctest.DocTest(docstring, globs, 'some_test', 'some_file', 20)
    >>> print test
    <DocTest some_test from some_file:20 (2 examples)>
    >>> len(test.examples)
    2
    >>> e1, e2 = test.examples
    >>> (e1.source, e1.want, e1.lineno)
    ('print 12', '12\n', 1)
    >>> (e2.source, e2.want, e2.lineno)
    ("print 'another\\example'", 'another\nexample\n', 6)

Source information (name, filename, and line number) is available as
attributes on the doctest object:

    >>> (test.name, test.filename, test.lineno)
    ('some_test', 'some_file', 20)

The line number of an example within its containing file is found by
adding the line number of the example and the line number of its
containing test:

    >>> test.lineno + e1.lineno
    21
    >>> test.lineno + e2.lineno
    26

If the docstring contains inconsistant leading whitespace in the
expected output of an example, then `DocTest` will raise a ValueError:

    >>> docstring = r'''
    ...       >>> print 'bad\nindentation'
    ...       bad
    ...     indentation
    ...     '''
    >>> doctest.DocTest(docstring, globs, 'some_test', 'filename', 0)
    Traceback (most recent call last):
    ValueError: line 3 of the docstring for some_test has inconsistent leading whitespace: '    indentation'

If the docstring contains inconsistent leading whitespace on
continuation lines, then `DocTest` will raise a ValueError:

    >>> docstring = r'''
    ...       >>> print ('bad indentation',
    ...     ...          2)
    ...       ('bad', 'indentation')
    ...     '''
    >>> doctest.DocTest(docstring, globs, 'some_test', 'filename', 0)
    Traceback (most recent call last):
    ValueError: line 2 of the docstring for some_test has inconsistent leading whitespace: '    ...          2)'

If there's no blank space after a PS1 prompt ('>>>'), then `DocTest`
will raise a ValueError:

    >>> docstring = '>>>print 1\n1'
    >>> doctest.DocTest(docstring, globs, 'some_test', 'filename', 0)
    Traceback (most recent call last):
    ValueError: line 0 of the docstring for some_test lacks blank after >>>: '>>>print 1'
"""

# [XX] test that it's getting line numbers right.
def test_DocTestFinder(): r"""
Unit tests for the `DocTestFinder` class.

DocTestFinder is used to extract DocTests from an object's docstring
and the docstrings of its contained objects.  It can be used with
modules, functions, classes, methods, staticmethods, classmethods, and
properties.

Finding Tests in Functions
~~~~~~~~~~~~~~~~~~~~~~~~~~
For a function whose docstring contains examples, DocTestFinder.find()
will return a single test (for that function's docstring):

    >>> # Allow ellipsis in the following examples (since the filename
    >>> # and line number in the traceback can vary):
    >>> doctest: +ELLIPSIS

    >>> finder = doctest.DocTestFinder()
    >>> tests = finder.find(sample_func)
    >>> print tests
    [<DocTest sample_func from ...:12 (1 example)>]
    >>> e = tests[0].examples[0]
    >>> print (e.source, e.want, e.lineno)
    ('print sample_func(22)', '44\n', 1)

    >>> doctest: -ELLIPSIS # Turn ellipsis back off

If an object has no docstring, then a test is not created for it:

    >>> def no_docstring(v):
    ...     pass
    >>> finder.find(no_docstring)
    []

If the function has a docstring with no examples, then a test with no
examples is returned.  (This lets `DocTestRunner` collect statistics
about which functions have no tests -- but is that useful?  And should
an empty test also be created when there's no docstring?)

    >>> def no_examples(v):
    ...     ''' no doctest examples '''
    >>> finder.find(no_examples)
    [<DocTest no_examples from None:1 (no examples)>]

Finding Tests in Classes
~~~~~~~~~~~~~~~~~~~~~~~~
For a class, DocTestFinder will create a test for the class's
docstring, and will recursively explore its contents, including
methods, classmethods, staticmethods, properties, and nested classes.

    >>> finder = doctest.DocTestFinder()
    >>> tests = finder.find(SampleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleClass
     3  SampleClass.NestedClass
     1  SampleClass.NestedClass.__init__
     1  SampleClass.__init__
     2  SampleClass.a_classmethod
     1  SampleClass.a_property
     1  SampleClass.a_staticmethod
     1  SampleClass.double
     1  SampleClass.get

New-style classes are also supported:

    >>> tests = finder.find(SampleNewStyleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleNewStyleClass
     1  SampleNewStyleClass.__init__
     1  SampleNewStyleClass.double
     1  SampleNewStyleClass.get

Finding Tests in Modules
~~~~~~~~~~~~~~~~~~~~~~~~
For a module, DocTestFinder will create a test for the class's
docstring, and will recursively explore its contents, including
functions, classes, and the `__test__` dictionary, if it exists:

    >>> # A module
    >>> import new
    >>> m = new.module('some_module')
    >>> def triple(val):
    ...     '''
    ...     >>> print tripple(11)
    ...     33
    ...     '''
    ...     return val*3
    >>> m.__dict__.update({
    ...     'sample_func': sample_func,
    ...     'SampleClass': SampleClass,
    ...     '__doc__': '''
    ...         Module docstring.
    ...             >>> print 'module'
    ...             module
    ...         ''',
    ...     '__test__': {
    ...         'd': '>>> print 6\n6\n>>> print 7\n7\n',
    ...         'c': triple}})

    >>> finder = doctest.DocTestFinder()
    >>> # Use module=test.test_doctest, to prevent doctest from
    >>> # ignoring the objects since they weren't defined in m.
    >>> import test.test_doctest
    >>> tests = finder.find(m, module=test.test_doctest)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  some_module
     1  some_module.SampleClass
     3  some_module.SampleClass.NestedClass
     1  some_module.SampleClass.NestedClass.__init__
     1  some_module.SampleClass.__init__
     2  some_module.SampleClass.a_classmethod
     1  some_module.SampleClass.a_property
     1  some_module.SampleClass.a_staticmethod
     1  some_module.SampleClass.double
     1  some_module.SampleClass.get
     1  some_module.c
     2  some_module.d
     1  some_module.sample_func

Duplicate Removal
~~~~~~~~~~~~~~~~~
If a single object is listed twice (under different names), then tests
will only be generated for it once:

    >>> class TwoNames:
    ...     '''f() and g() are two names for the same method'''
    ...
    ...     def f(self):
    ...         '''
    ...         >>> print TwoNames().f()
    ...         f
    ...         '''
    ...         return 'f'
    ...
    ...     g = f # define an alias for f.

    >>> finder = doctest.DocTestFinder()
    >>> tests = finder.find(TwoNames, ignore_imports=False)
    >>> tests.sort()
    >>> print len(tests)
    2
    >>> print tests[0].name
    TwoNames
    >>> print tests[1].name in ('TwoNames.f', 'TwoNames.g')
    True

Filter Functions
~~~~~~~~~~~~~~~~
Two filter functions can be used to restrict which objects get
examined: a name-based filter and an object-based filter.

    >>> def namefilter(prefix, base):
    ...     return base.startswith('a_')
    >>> tests = doctest.DocTestFinder(namefilter=namefilter).find(SampleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleClass
     3  SampleClass.NestedClass
     1  SampleClass.NestedClass.__init__
     1  SampleClass.__init__
     1  SampleClass.double
     1  SampleClass.get

    >>> def objfilter(obj):
    ...     return isinstance(obj, (staticmethod, classmethod))
    >>> tests = doctest.DocTestFinder(objfilter=objfilter).find(SampleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleClass
     3  SampleClass.NestedClass
     1  SampleClass.NestedClass.__init__
     1  SampleClass.__init__
     1  SampleClass.a_property
     1  SampleClass.double
     1  SampleClass.get

If a given object is filtered out, then none of the objects that it
contains will be added either:

    >>> def namefilter(prefix, base):
    ...     return base == 'NestedClass'
    >>> tests = doctest.DocTestFinder(namefilter=namefilter).find(SampleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleClass
     1  SampleClass.__init__
     2  SampleClass.a_classmethod
     1  SampleClass.a_property
     1  SampleClass.a_staticmethod
     1  SampleClass.double
     1  SampleClass.get

The filter functions apply to contained objects, and *not* to the
object explicitly passed to DocTestFinder:

    >>> def namefilter(prefix, base):
    ...     return base == 'SampleClass'
    >>> tests = doctest.DocTestFinder(namefilter=namefilter).find(SampleClass)
    >>> len(tests)
    9

Turning off Recursion
~~~~~~~~~~~~~~~~~~~~~
DocTestFinder can be told not to look for tests in contained objects
using the `recurse` flag:

    >>> tests = doctest.DocTestFinder(recurse=False).find(SampleClass)
    >>> tests.sort()
    >>> for t in tests:
    ...     print '%2s  %s' % (len(t.examples), t.name)
     1  SampleClass
"""

class test_DocTestRunner:
    def basics(): r"""
Unit tests for the `DocTestRunner` class.

DocTestRunner is used to run DocTest test cases, and to accumulate
statistics.  Here's a simple DocTest case we can use:

    >>> def f(x):
    ...     '''
    ...     >>> x = 12
    ...     >>> print x
    ...     12
    ...     >>> x/2
    ...     6
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]

The main DocTestRunner interface is the `run` method, which runs a
given DocTest case in a given namespace (globs).  It returns a tuple
`(f,t)`, where `f` is the number of failed tests and `t` is the number
of tried tests.

    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 3)

If any example produces incorrect output, then the test runner reports
the failure and proceeds to the next example:

    >>> def f(x):
    ...     '''
    ...     >>> x = 12
    ...     >>> print x
    ...     14
    ...     >>> x/2
    ...     6
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=True).run(test)
    Trying: x = 12
    Expecting: nothing
    ok
    Trying: print x
    Expecting: 14
    **********************************************************************
    Failure in example: print x
    from line #2 of f
    Expected: 14
    Got: 12
    Trying: x/2
    Expecting: 6
    ok
    (1, 3)
"""
    def verbose_flag(): r"""
The `verbose` flag makes the test runner generate more detailed
output:

    >>> def f(x):
    ...     '''
    ...     >>> x = 12
    ...     >>> print x
    ...     12
    ...     >>> x/2
    ...     6
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]

    >>> doctest.DocTestRunner(verbose=True).run(test)
    Trying: x = 12
    Expecting: nothing
    ok
    Trying: print x
    Expecting: 12
    ok
    Trying: x/2
    Expecting: 6
    ok
    (0, 3)

If the `verbose` flag is unspecified, then the output will be verbose
iff `-v` appears in sys.argv:

    >>> # Save the real sys.argv list.
    >>> old_argv = sys.argv

    >>> # If -v does not appear in sys.argv, then output isn't verbose.
    >>> sys.argv = ['test']
    >>> doctest.DocTestRunner().run(test)
    (0, 3)

    >>> # If -v does appear in sys.argv, then output is verbose.
    >>> sys.argv = ['test', '-v']
    >>> doctest.DocTestRunner().run(test)
    Trying: x = 12
    Expecting: nothing
    ok
    Trying: print x
    Expecting: 12
    ok
    Trying: x/2
    Expecting: 6
    ok
    (0, 3)

    >>> # Restore sys.argv
    >>> sys.argv = old_argv

In the remaining examples, the test runner's verbosity will be
explicitly set, to ensure that the test behavior is consistent.
    """
    def exceptions(): r"""
Tests of `DocTestRunner`'s exception handling.

An expected exception is specified with a traceback message.  The
lines between the first line and the type/value may be omitted or
replaced with any other string:

    >>> def f(x):
    ...     '''
    ...     >>> x = 12
    ...     >>> print x/0
    ...     Traceback (most recent call last):
    ...     ZeroDivisionError: integer division or modulo by zero
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 2)

An example may generate output before it raises an exception; if it
does, then the output must match the expected output:

    >>> def f(x):
    ...     '''
    ...     >>> x = 12
    ...     >>> print 'pre-exception output', x/0
    ...     pre-exception output
    ...     Traceback (most recent call last):
    ...     ZeroDivisionError: integer division or modulo by zero
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 2)

Exception messages may contain newlines:

    >>> def f(x):
    ...     r'''
    ...     >>> raise ValueError, 'multi\nline\nmessage'
    ...     Traceback (most recent call last):
    ...     ValueError: multi
    ...     line
    ...     message
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 1)

If an exception is expected, but an exception with the wrong type or
message is raised, then it is reported as a failure:

    >>> def f(x):
    ...     r'''
    ...     >>> raise ValueError, 'message'
    ...     Traceback (most recent call last):
    ...     ValueError: wrong message
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: raise ValueError, 'message'
    from line #1 of f
    Expected:
        Traceback (most recent call last):
        ValueError: wrong message
    Got:
        Traceback (most recent call last):
        ValueError: message
    (1, 1)

If an exception is raised but not expected, then it is reported as an
unexpected exception:

    >>> # Allow ellipsis in the following examples (since the filename
    >>> # and line number in the traceback can vary):
    >>> doctest: +ELLIPSIS

    >>> def f(x):
    ...     r'''
    ...     >>> 1/0
    ...     0
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: 1/0
    from line #1 of f
    Exception raised:
        Traceback (most recent call last):
          ...
        ZeroDivisionError: integer division or modulo by zero
    (1, 1)

    >>> doctest: -ELLIPSIS # Turn ellipsis back off:
"""
    def optionflags(): r"""
Tests of `DocTestRunner`'s option flag handling.

Several option flags can be used to customize the behavior of the test
runner.  These are defined as module constants in doctest, and passed
to the DocTestRunner constructor (multiple constants should be or-ed
together).

The DONT_ACCEPT_TRUE_FOR_1 flag disables matches between True/False
and 1/0:

    >>> def f(x):
    ...     '>>> True\n1\n'

    >>> # Without the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 1)

    >>> # With the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.DONT_ACCEPT_TRUE_FOR_1
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    **********************************************************************
    Failure in example: True
    from line #0 of f
    Expected: 1
    Got: True
    (1, 1)

The DONT_ACCEPT_BLANKLINE flag disables the match between blank lines
and the '<BLANKLINE>' marker:

    >>> def f(x):
    ...     '>>> print "a\\n\\nb"\na\n<BLANKLINE>\nb\n'

    >>> # Without the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    (0, 1)

    >>> # With the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.DONT_ACCEPT_BLANKLINE
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    **********************************************************************
    Failure in example: print "a\n\nb"
    from line #0 of f
    Expected:
        a
        <BLANKLINE>
        b
    Got:
        a
    <BLANKLINE>
        b
    (1, 1)

The NORMALIZE_WHITESPACE flag causes all sequences of whitespace to be
treated as equal:

    >>> def f(x):
    ...     '>>> print 1, 2, 3\n  1   2\n 3'

    >>> # Without the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: print 1, 2, 3
    from line #0 of f
    Expected:
          1   2
         3
    Got: 1 2 3
    (1, 1)

    >>> # With the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.NORMALIZE_WHITESPACE
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    (0, 1)

The ELLIPSIS flag causes ellipsis marker ("...") in the expected
output to match any substring in the actual output:

    >>> def f(x):
    ...     '>>> print range(15)\n[0, 1, 2, ..., 14]\n'

    >>> # Without the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: print range(15)
    from line #0 of f
    Expected: [0, 1, 2, ..., 14]
    Got: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]
    (1, 1)

    >>> # With the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.ELLIPSIS
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    (0, 1)

The UNIFIED_DIFF flag causes failures that involve multi-line expected
and actual outputs to be displayed using a unified diff:

    >>> def f(x):
    ...     r'''
    ...     >>> print '\n'.join('abcdefg')
    ...     a
    ...     B
    ...     c
    ...     d
    ...     f
    ...     g
    ...     h
    ...     '''

    >>> # Without the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: print '\n'.join('abcdefg')
    from line #1 of f
    Expected:
        a
        B
        c
        d
        f
        g
        h
    Got:
        a
        b
        c
        d
        e
        f
        g
    (1, 1)

    >>> # With the flag:
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.UNIFIED_DIFF
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    **********************************************************************
    Failure in example: print '\n'.join('abcdefg')
    from line #1 of f
    Differences (unified diff):
        --- Expected
        +++ Got
        @@ -1,8 +1,8 @@
         a
        -B
        +b
         c
         d
        +e
         f
         g
        -h
    <BLANKLINE>
    (1, 1)

The CONTEXT_DIFF flag causes failures that involve multi-line expected
and actual outputs to be displayed using a context diff:

    >>> # Reuse f() from the UNIFIED_DIFF example, above.
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> flags = doctest.CONTEXT_DIFF
    >>> doctest.DocTestRunner(verbose=False, optionflags=flags).run(test)
    **********************************************************************
    Failure in example: print '\n'.join('abcdefg')
    from line #1 of f
    Differences (context diff):
        *** Expected
        --- Got
        ***************
        *** 1,8 ****
          a
        ! B
          c
          d
          f
          g
        - h
    <BLANKLINE>
        --- 1,8 ----
          a
        ! b
          c
          d
        + e
          f
          g
    <BLANKLINE>
    (1, 1)
"""
    def option_directives(): r"""
Tests of `DocTestRunner`'s option directive mechanism.

Option directives can be used to turn option flags on or off from
within a DocTest case.  The following example shows how a flag can be
turned on and off.  Note that comments on the same line as the option
directive are ignored.

    >>> def f(x): r'''
    ...     >>> print range(10)       # Should fail: no ellipsis
    ...     [0, 1, ..., 9]
    ...
    ...     >>> doctest: +ELLIPSIS    # turn ellipsis on.
    ...     >>> print range(10)       # Should succeed
    ...     [0, 1, ..., 9]
    ...
    ...     >>> doctest: -ELLIPSIS    # turn ellipsis back off.
    ...     >>> print range(10)       # Should fail: no ellipsis
    ...     [0, 1, ..., 9]
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: print range(10)       # Should fail: no ellipsis
    from line #1 of f
    Expected: [0, 1, ..., 9]
    Got: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
    **********************************************************************
    Failure in example: print range(10)       # Should fail: no ellipsis
    from line #9 of f
    Expected: [0, 1, ..., 9]
    Got: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
    (2, 3)

Multiple flags can be toggled by a single option directive:

    >>> def f(x): r'''
    ...     >>> print range(10)       # Should fail
    ...     [0, 1,  ...,   9]
    ...     >>> doctest: +ELLIPSIS +NORMALIZE_WHITESPACE
    ...     >>> print range(10)       # Should succeed
    ...     [0, 1,  ...,   9]
    ...     '''
    >>> test = doctest.DocTestFinder().find(f)[0]
    >>> doctest.DocTestRunner(verbose=False).run(test)
    **********************************************************************
    Failure in example: print range(10)       # Should fail
    from line #1 of f
    Expected: [0, 1,  ...,   9]
    Got: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
    (1, 2)
"""

def test_testsource(): r"""
Unit tests for `testsource()`.

The testsource() function takes a module and a name, finds the (first)
test with that name in that module, and converts it to an

    >>> import test.test_doctest
    >>> name = 'test.test_doctest.sample_func'
    >>> print doctest.testsource(test.test_doctest, name)
    print sample_func(22)
    # Expected:
    #     44

    >>> name = 'test.test_doctest.SampleNewStyleClass'
    >>> print doctest.testsource(test.test_doctest, name)
    print '1\n2\n3'
    # Expected:
    #     1
    #     2
    #     3

    >>> name = 'test.test_doctest.SampleClass.a_classmethod'
    >>> print doctest.testsource(test.test_doctest, name)
    print SampleClass.a_classmethod(10)
    # Expected:
    #     12
    print SampleClass(0).a_classmethod(10)
    # Expected:
    #     12
"""

def test_debug(): r"""

Create a docstring that we want to debug:

    >>> s = '''
    ...     >>> x = 12
    ...     >>> print x
    ...     12
    ...     '''

Create some fake stdin input, to feed to the debugger:

    >>> import tempfile
    >>> fake_stdin = tempfile.TemporaryFile(mode='w+')
    >>> fake_stdin.write('\n'.join(['next', 'print x', 'continue', '']))
    >>> fake_stdin.seek(0)
    >>> real_stdin = sys.stdin
    >>> sys.stdin = fake_stdin

Run the debugger on the docstring, and then restore sys.stdin.

    >>> doctest: +NORMALIZE_WHITESPACE
    >>> try:
    ...     doctest.debug_src(s)
    ... finally:
    ...      sys.stdin = real_stdin
    ...      fake_stdin.close()
    > <string>(1)?()
    (Pdb) 12
    --Return--
    > <string>(1)?()->None
    (Pdb) 12
    (Pdb)

"""

######################################################################
## Main
######################################################################

def test_main():
    # Check the doctest cases in doctest itself:
    test_support.run_doctest(doctest, verbosity=True)
    # Check the doctest cases defined here:
    from test import test_doctest
    test_support.run_doctest(test_doctest, verbosity=True)

import trace, sys, re, StringIO
def test_coverage(coverdir):
    tracer = trace.Trace(ignoredirs=[sys.prefix, sys.exec_prefix,],
                         trace=0, count=1)
    tracer.run('reload(doctest); test_main()')
    r = tracer.results()
    print 'Writing coverage results...'
    r.write_results(show_missing=True, summary=True,
                    coverdir=coverdir)

if __name__ == '__main__':
    if '-c' in sys.argv:
        test_coverage('/tmp/doctest.cover')
    else:
        test_main()