From 6a90b3afa67416a79d036a11880da4d33aad8e30 2022-10-29 11:18:09
From: Osher De Paz <osherdepaz@gmail.com>
Date: 2022-10-29 11:18:09
Subject: [PATCH] raise an error when user tries to open a standard stream

Fixes #13718

---

diff --git a/IPython/core/interactiveshell.py b/IPython/core/interactiveshell.py
index 6d04846..e9cc89a 100644
--- a/IPython/core/interactiveshell.py
+++ b/IPython/core/interactiveshell.py
@@ -1255,6 +1255,15 @@ class InteractiveShell(SingletonConfigurable):
         if user_ns is None:
             user_ns = user_module.__dict__
 
+        @functools.wraps(io_open)
+        def modified_open(file, *args, **kwargs):
+            if file in {0, 1, 2}:
+                raise ValueError(f"IPython won't let you open fd={file} by default")
+
+            return io_open(file, *args, **kwargs)
+
+        user_ns["open"] = modified_open
+
         return user_module, user_ns
 
     def init_sys_modules(self):
diff --git a/IPython/core/tests/test_interactiveshell.py b/IPython/core/tests/test_interactiveshell.py
index 10827b5..b5efe98 100644
--- a/IPython/core/tests/test_interactiveshell.py
+++ b/IPython/core/tests/test_interactiveshell.py
@@ -103,6 +103,21 @@ class InteractiveShellTestCase(unittest.TestCase):
         res = ip.run_cell("raise = 3")
         self.assertIsInstance(res.error_before_exec, SyntaxError)
 
+    def test_open_standard_input_stream(self):
+        ip.init_create_namespaces()
+        res = ip.run_cell("open(0)")
+        self.assertIsInstance(res.error_in_exec, ValueError)
+
+    def test_open_standard_output_stream(self):
+        ip.init_create_namespaces()
+        res = ip.run_cell("open(1)")
+        self.assertIsInstance(res.error_in_exec, ValueError)
+
+    def test_open_standard_error_stream(self):
+        ip.init_create_namespaces()
+        res = ip.run_cell("open(2)")
+        self.assertIsInstance(res.error_in_exec, ValueError)
+
     def test_In_variable(self):
         "Verify that In variable grows with user input (GH-284)"
         oldlen = len(ip.user_ns['In'])