bpo-37409: fix relative import with no parent (#14956)
Relative imports use resolve_name to get the absolute target name,
which first seeks the current module's absolute package name from the globals:
If __package__ (and __spec__.parent) are missing then
import uses __name__, truncating the last segment if
the module is a submodule rather than a package __init__.py
(which it guesses from whether __path__ is defined).
The __name__ attempt should fail if there is no parent package (top level modules),
if __name__ is '__main__' (-m entry points), or both (scripts).
That is, if both __name__ has no subcomponents and the module does not seem
to be a package __init__ module then import should fail.
diff --git a/Misc/ACKS b/Misc/ACKS
index 6318998..d37d2bd 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -975,6 +975,7 @@
Mark Levinson
Mark Levitt
Ivan Levkivskyi
+Ben Lewis
William Lewis
Akira Li
Robert Li
diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-08-06-23-39-05.bpo-37409.1qwzn2.rst b/Misc/NEWS.d/next/Core and Builtins/2019-08-06-23-39-05.bpo-37409.1qwzn2.rst
new file mode 100644
index 0000000..9cfa715
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2019-08-06-23-39-05.bpo-37409.1qwzn2.rst
@@ -0,0 +1,2 @@
+Ensure explicit relative imports from interactive sessions and scripts (having no parent package) always raise ImportError, rather than treating the current module as the package.
+Patch by Ben Lewis.