[3.9] bpo-40924: Remove protocol for supplying Traversable objects from loaders (GH-20820)

jaraco · web-flow · commit 8a3469047c3c · 2020-06-14T14:12:20.000+02:00
Remove protocol that loaders can present a files method as found in importlib_resources 1.3-1.6 (added in Python 3.8b1).
diff --git a/Doc/library/importlib.rst b/Doc/library/importlib.rst
@@ -813,9 +813,6 @@ ABC hierarchy::
     methods. Therefore, any loader supplying TraversableReader
     also supplies ResourceReader.
 
-    Loaders that wish to support resource reading are expected to
-    implement this interface.
-
     .. versionadded:: 3.9
 
 
diff --git a/Lib/importlib/_common.py b/Lib/importlib/_common.py
@@ -11,17 +11,7 @@ def from_package(package):
     Return a Traversable object for the given package.
 
     """
-    spec = package.__spec__
-    return from_traversable_resources(spec) or fallback_resources(spec)
-
-
-def from_traversable_resources(spec):
-    """
-    If the spec.loader implements TraversableResources,
-    directly or implicitly, it will have a ``files()`` method.
-    """
-    with contextlib.suppress(AttributeError):
-        return spec.loader.files()
+    return fallback_resources(package.__spec__)
 
 
 def fallback_resources(spec):
diff --git a/Misc/NEWS.d/next/Library/2020-06-11-23-41-50.bpo-40924.m17Fkm.rst b/Misc/NEWS.d/next/Library/2020-06-11-23-41-50.bpo-40924.m17Fkm.rst
@@ -0,0 +1 @@
+Removed support for loaders implementing .files and supplying TraversableResources.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+Removed support for loaders implementing .files and supplying TraversableResources.`