gh-143082: Make readline work when sys.stdin is explicitly passed to pdb (#143083)

diff --git a/Lib/pdb.py b/Lib/pdb.py
index eee0273fdc463f975d431256d38903f25e35ef93..0464b288ef825ab72a487d2addb58a2a3a228a7b 100644 (file)
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -364,7 +364,7 @@ class Pdb(bdb.Bdb, cmd.Cmd):
         bdb.Bdb.__init__(self, skip=skip, backend=backend if backend else get_default_backend())
         cmd.Cmd.__init__(self, completekey, stdin, stdout)
         sys.audit("pdb.Pdb")
-        if stdin:
+        if stdin is not None and stdin is not sys.stdin:
             self.use_rawinput = False
         self.prompt = '(Pdb) '
         self.aliases = {}

diff --git a/Misc/NEWS.d/next/Windows/2025-12-25-00-38-20.gh-issue-143082.CYUeux.rst b/Misc/NEWS.d/next/Windows/2025-12-25-00-38-20.gh-issue-143082.CYUeux.rst
new file mode 100644 (file)
index 0000000..0652c4c
--- /dev/null
+++ b/Misc/NEWS.d/next/Windows/2025-12-25-00-38-20.gh-issue-143082.CYUeux.rst
@@ -0,0 +1 @@
+Fix :mod:`pdb` arrow key history not working when ``stdin`` is ``sys.stdin``.