diff --git a/Doc/library/reprlib.rst b/Doc/library/reprlib.rst index 1a0c1b0dcd1..f2b19577564 100644 --- a/Doc/library/reprlib.rst +++ b/Doc/library/reprlib.rst @@ -17,7 +17,9 @@ debugger and may be useful in other contexts as well. This module provides a class, an instance, and a function: -.. class:: Repr() +.. class:: Repr(self, *, maxlevel=6, maxtuple=6, maxlist=6, maxarray=5, \ + maxdict=4, maxset=6, maxfrozenset=6, maxdeque=6, maxstring=30, \ + maxlong=40, maxother=30) Class which provides formatting services useful in implementing functions similar to the built-in :func:`repr`; size limits for different object types @@ -71,72 +73,75 @@ string instead. Repr Objects ------------ -:class:`Repr` instances provide several attributes which can be used to provide -size limits for the representations of different object types, and methods -which format specific object types. +.. class:: Repr(self, *, maxlevel=6, maxtuple=6, maxlist=6, maxarray=5, \ + maxdict=4, maxset=6, maxfrozenset=6, maxdeque=6, maxstring=30, \ + maxlong=40, maxother=30) + + :class:`Repr` instances provide several attributes which can be used to provide + size limits for the representations of different object types, and methods + which format specific object types. + + .. attribute:: maxlevel + + Depth limit on the creation of recursive representations. The default is ``6``. -.. attribute:: Repr.maxlevel + .. attribute:: maxdict + maxlist + maxtuple + maxset + maxfrozenset + maxdeque + maxarray - Depth limit on the creation of recursive representations. The default is ``6``. + Limits on the number of entries represented for the named object type. The + default is ``4`` for :attr:`maxdict`, ``5`` for :attr:`maxarray`, and ``6`` for + the others. -.. attribute:: Repr.maxdict - Repr.maxlist - Repr.maxtuple - Repr.maxset - Repr.maxfrozenset - Repr.maxdeque - Repr.maxarray + .. attribute:: maxlong - Limits on the number of entries represented for the named object type. The - default is ``4`` for :attr:`maxdict`, ``5`` for :attr:`maxarray`, and ``6`` for - the others. + Maximum number of characters in the representation for an integer. Digits + are dropped from the middle. The default is ``40``. -.. attribute:: Repr.maxlong + .. attribute:: maxstring - Maximum number of characters in the representation for an integer. Digits - are dropped from the middle. The default is ``40``. + Limit on the number of characters in the representation of the string. Note + that the "normal" representation of the string is used as the character source: + if escape sequences are needed in the representation, these may be mangled when + the representation is shortened. The default is ``30``. -.. attribute:: Repr.maxstring + .. attribute:: maxother - Limit on the number of characters in the representation of the string. Note - that the "normal" representation of the string is used as the character source: - if escape sequences are needed in the representation, these may be mangled when - the representation is shortened. The default is ``30``. + This limit is used to control the size of object types for which no specific + formatting method is available on the :class:`Repr` object. It is applied in a + similar manner as :attr:`maxstring`. The default is ``20``. -.. attribute:: Repr.maxother + .. method:: repr(obj) - This limit is used to control the size of object types for which no specific - formatting method is available on the :class:`Repr` object. It is applied in a - similar manner as :attr:`maxstring`. The default is ``20``. + The equivalent to the built-in :func:`repr` that uses the formatting imposed by + the instance. -.. method:: Repr.repr(obj) + .. method:: repr1(obj, level) - The equivalent to the built-in :func:`repr` that uses the formatting imposed by - the instance. + Recursive implementation used by :meth:`.repr`. This uses the type of *obj* to + determine which formatting method to call, passing it *obj* and *level*. The + type-specific methods should call :meth:`repr1` to perform recursive formatting, + with ``level - 1`` for the value of *level* in the recursive call. -.. method:: Repr.repr1(obj, level) + .. method:: repr_TYPE(obj, level) + :noindex: - Recursive implementation used by :meth:`.repr`. This uses the type of *obj* to - determine which formatting method to call, passing it *obj* and *level*. The - type-specific methods should call :meth:`repr1` to perform recursive formatting, - with ``level - 1`` for the value of *level* in the recursive call. - - -.. method:: Repr.repr_TYPE(obj, level) - :noindex: - - Formatting methods for specific types are implemented as methods with a name - based on the type name. In the method name, **TYPE** is replaced by - ``'_'.join(type(obj).__name__.split())``. Dispatch to these methods is - handled by :meth:`repr1`. Type-specific methods which need to recursively - format a value should call ``self.repr1(subobj, level - 1)``. + Formatting methods for specific types are implemented as methods with a name + based on the type name. In the method name, **TYPE** is replaced by + ``'_'.join(type(obj).__name__.split())``. Dispatch to these methods is + handled by :meth:`repr1`. Type-specific methods which need to recursively + format a value should call ``self.repr1(subobj, level - 1)``. .. _subclassing-reprs: diff --git a/Lib/reprlib.py b/Lib/reprlib.py index 616b3439b5d..42e59bf0a2f 100644 --- a/Lib/reprlib.py +++ b/Lib/reprlib.py @@ -33,20 +33,23 @@ def recursive_repr(fillvalue='...'): return decorating_function + class Repr: - def __init__(self): - self.maxlevel = 6 - self.maxtuple = 6 - self.maxlist = 6 - self.maxarray = 5 - self.maxdict = 4 - self.maxset = 6 - self.maxfrozenset = 6 - self.maxdeque = 6 - self.maxstring = 30 - self.maxlong = 40 - self.maxother = 30 + def __init__(self, *, maxlevel=6, maxtuple=6, maxlist=6, maxarray=5, + maxdict=4, maxset=6, maxfrozenset=6, maxdeque=6, maxstring=30, + maxlong=40, maxother=30): + self.maxlevel = maxlevel + self.maxtuple = maxtuple + self.maxlist = maxlist + self.maxarray = maxarray + self.maxdict = maxdict + self.maxset = maxset + self.maxfrozenset = maxfrozenset + self.maxdeque = maxdeque + self.maxstring = maxstring + self.maxlong = maxlong + self.maxother = maxother def repr(self, x): return self.repr1(x, self.maxlevel) diff --git a/Lib/test/test_reprlib.py b/Lib/test/test_reprlib.py index 4bf91945ea4..e36b26bedf1 100644 --- a/Lib/test/test_reprlib.py +++ b/Lib/test/test_reprlib.py @@ -216,6 +216,13 @@ class ReprTests(unittest.TestCase): r(y) r(z) + def test___init__(self): + a = "a"*40 + r = Repr() + self.assertEqual(r.repr(a), "'aaaaaaaaaaaa...aaaaaaaaaaaaa'") + r = Repr(maxstring=10) + self.assertEqual(r.repr(a), "'aa...aaa'") + def write_file(path, text): with open(path, 'w', encoding='ASCII') as fp: fp.write(text) diff --git a/Misc/NEWS.d/next/Library/2020-06-17-01-07-36.bpo-40995.2IvRr2.rst b/Misc/NEWS.d/next/Library/2020-06-17-01-07-36.bpo-40995.2IvRr2.rst new file mode 100644 index 00000000000..687826af653 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-06-17-01-07-36.bpo-40995.2IvRr2.rst @@ -0,0 +1,2 @@ +:class:`reprlib.Repr` attributes can now be set when creating an instance. +Patch contributed by RĂ©mi Lapeyre.