bpo-34871: inspect: Don't pollute sys.modules (GH-9696)

https://bugs.python.org/issue34871

diff --git a/Lib/inspect.py b/Lib/inspect.py
index 5b7f526939b60ffe9ce76924520fa8c891892484..857892bc8144c563b5139286330a04452dbd4f0e 100644 (file)
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -1988,7 +1988,7 @@ def _signature_fromstr(cls, obj, s, skip_bound_arg=True):
         module = sys.modules.get(module_name, None)
         if module:
             module_dict = module.__dict__
-    sys_module_dict = sys.modules
+    sys_module_dict = sys.modules.copy()
 
     def parse_name(node):
         assert isinstance(node, ast.arg)

diff --git a/Misc/NEWS.d/next/Library/2018-10-04-18-46-54.bpo-34871.t3X-dB.rst b/Misc/NEWS.d/next/Library/2018-10-04-18-46-54.bpo-34871.t3X-dB.rst
new file mode 100644 (file)
index 0000000..8cff156
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-10-04-18-46-54.bpo-34871.t3X-dB.rst
@@ -0,0 +1,2 @@
+Fix inspect module polluted ``sys.modules`` when parsing
+``__text_signature__`` of callable.