From eaefa0b1f789443075fe867e8657fd9faa283f1b Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Fri, 15 Mar 2024 10:55:44 +0100
Subject: [PATCH] [3.11] gh-90095: Ignore empty lines and comments in `.pdbrc`
 (GH-116834) (#116855)

gh-90095: Ignore empty lines and comments in `.pdbrc` (GH-116834)
(cherry picked from commit a50cf6c3d76b34e2ee9f92a248f1b0df24e407f6)

Co-authored-by: Tian Gao <gaogaotiantian@hotmail.com>
---
 Doc/library/pdb.rst                           |  3 ++-
 Lib/pdb.py                                    |  5 ++++-
 Lib/test/test_pdb.py                          | 19 +++++++++++++++++++
 ...4-03-14-20-59-28.gh-issue-90095.7UaJ1U.rst |  1 +
 4 files changed, 26 insertions(+), 2 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2024-03-14-20-59-28.gh-issue-90095.7UaJ1U.rst

diff --git a/Doc/library/pdb.rst b/Doc/library/pdb.rst
index a845d5512ff..1a949a2679d 100644
--- a/Doc/library/pdb.rst
+++ b/Doc/library/pdb.rst
@@ -269,7 +269,8 @@ is to use implicit string concatenation ``';'';'`` or ``";"";"``.
 
 If a file :file:`.pdbrc` exists in the user's home directory or in the current
 directory, it is read with ``'utf-8'`` encoding and executed as if it had been
-typed at the debugger prompt.  This is particularly useful for aliases.  If both
+typed at the debugger prompt, with the exception that empty lines and lines
+starting with ``#`` are ignored.  This is particularly useful for aliases.  If both
 files exist, the one in the home directory is read first and aliases defined there
 can be overridden by the local file.
 
diff --git a/Lib/pdb.py b/Lib/pdb.py
index fd73f14a7ea..3077b0bfa52 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -297,7 +297,10 @@ def setup(self, f, tb):
         self.curframe_locals = self.curframe.f_locals
 
         if self.rcLines:
-            self.cmdqueue = self.rcLines
+            self.cmdqueue = [
+                line for line in self.rcLines
+                if line.strip() and not line.strip().startswith("#")
+            ]
             self.rcLines = []
 
     # Override Bdb methods
diff --git a/Lib/test/test_pdb.py b/Lib/test/test_pdb.py
index 941031a5a9f..d21ea9e5f7c 100644
--- a/Lib/test/test_pdb.py
+++ b/Lib/test/test_pdb.py
@@ -2061,8 +2061,27 @@ def test_pdbrc_basic(self):
         """)
 
         stdout, stderr = self.run_pdb_script(script, 'q\n', pdbrc=pdbrc, remove_home=True)
+        self.assertNotIn("SyntaxError", stdout)
         self.assertIn("a+8=9", stdout)
 
+    def test_pdbrc_empty_line(self):
+        """Test that empty lines in .pdbrc are ignored."""
+
+        script = textwrap.dedent("""
+            a = 1
+            b = 2
+            c = 3
+        """)
+
+        pdbrc = textwrap.dedent("""
+            n
+
+        """)
+
+        stdout, stderr = self.run_pdb_script(script, 'q\n', pdbrc=pdbrc, remove_home=True)
+        self.assertIn("b = 2", stdout)
+        self.assertNotIn("c = 3", stdout)
+
     def test_pdbrc_alias(self):
         script = textwrap.dedent("""
             class A:
diff --git a/Misc/NEWS.d/next/Library/2024-03-14-20-59-28.gh-issue-90095.7UaJ1U.rst b/Misc/NEWS.d/next/Library/2024-03-14-20-59-28.gh-issue-90095.7UaJ1U.rst
new file mode 100644
index 00000000000..b7024c74f7a
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-03-14-20-59-28.gh-issue-90095.7UaJ1U.rst
@@ -0,0 +1 @@
+Ignore empty lines and comments in ``.pdbrc``