diff options
| -rwxr-xr-x | CHANGES.txt | 2 | ||||
| -rw-r--r-- | SCons/Util.py | 34 |
2 files changed, 16 insertions, 20 deletions
diff --git a/CHANGES.txt b/CHANGES.txt index e6d0a67..f6dbf5f 100755 --- a/CHANGES.txt +++ b/CHANGES.txt @@ -78,6 +78,8 @@ RELEASE VERSION/DATE TO BE FILLED IN LATER - Make sure when subst'ing a callable, the callable is called with the correct for_signature value, previously it would be true even if doing SUBST_RAW (issue #4037) + - Update Util/NodeList implementation to get rid of a workaround for + early Python 3 slicing issue that is no longer a problem. From Brian Quistorff: diff --git a/SCons/Util.py b/SCons/Util.py index 1045ccf..0dd6ff1 100644 --- a/SCons/Util.py +++ b/SCons/Util.py @@ -119,10 +119,14 @@ def updrive(path) -> str: class NodeList(UserList): """A list of Nodes with special attribute retrieval. - This class is almost exactly like a regular list of Nodes - (actually it can hold any object), with one important difference. - If you try to get an attribute from this list, it will return that - attribute from every item in the list. For example: + Unlike an ordinary list, access to a member's attribute returns a + `NodeList` containing the same attribute for each member. Although + this can hold any object, it is intended for use when processing + Nodes, where fetching an attribute of each member is very commone, + for example getting the content signature of each node. The term + "attribute" here includes the string representation. + + Example: >>> someList = NodeList([' foo ', ' bar ']) >>> someList.strip() @@ -138,30 +142,20 @@ class NodeList(UserList): def __iter__(self): return iter(self.data) - def __call__(self, *args, **kwargs): + def __call__(self, *args, **kwargs) -> 'NodeList': result = [x(*args, **kwargs) for x in self.data] return self.__class__(result) - def __getattr__(self, name): + def __getattr__(self, name) -> 'NodeList': + """Returns a NodeList of `name` from each member.""" result = [getattr(x, name) for x in self.data] return self.__class__(result) def __getitem__(self, index): - """ - This comes for free on py2, - but py3 slices of NodeList are returning a list - breaking slicing nodelist and refering to - properties and methods on contained object - """ -# return self.__class__(self.data[index]) - + """Returns one item, forces a `NodeList` if `index` is a slice.""" + # TODO: annotate return how? Union[] - don't know type of single item if isinstance(index, slice): - # Expand the slice object using range() - # limited by number of items in self.data - indices = index.indices(len(self.data)) - return self.__class__([self[x] for x in range(*indices)]) - - # Return one item of the tart + return self.__class__(self.data[index]) return self.data[index] |