[3.12] gh-90095: Ignore empty lines and comments in .pdbrc (GH-116834) (#116854)

miss-islington · gaogaotiantian · web-flow · commit abd079806d5f · 2024-03-15T09:52:00.000Z
gh-90095: Ignore empty lines and comments in `.pdbrc` (GH-116834) (cherry picked from commit a50cf6c) Co-authored-by: Tian Gao <gaogaotiantian@hotmail.com>
diff --git a/Doc/library/pdb.rst b/Doc/library/pdb.rst
@@ -284,7 +284,8 @@ There are three preset *convenience variables*:
 
 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
@@ -301,7 +301,10 @@ def setup(self, f, tb):
         self.set_convenience_variable(self.curframe, '_frame', self.curframe)
 
         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
@@ -2212,8 +2212,27 @@ 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
@@ -0,0 +1 @@
+Ignore empty lines and comments in ``.pdbrc``

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+Ignore empty lines and comments in ``.pdbrc``