python · iritkatriel · Mar 19, 2026 · Mar 18, 2026 · Mar 18, 2026 · Mar 18, 2026
@@ -234,6 +234,18 @@ class MyEG(ExceptionGroup):
            "ExceptionGroup('test', deque([ValueError(1), TypeError(2)]))"
        )

+    def test_repr_small_size_args(self):
+        eg = ExceptionGroup("msg", [ValueError()])
+        eg.args = ()
+        # repr of the ExceptionGroup with empty args should not crash
+        self.assertEqual(repr(eg), "ExceptionGroup('msg', (ValueError(),))")
+
+        eg.args = (1,)
+        # repr of the ExceptionGroup with 1-size args should not crash
+        self.assertEqual(repr(eg), "ExceptionGroup('msg', (ValueError(),))")
+
+
+
    def test_repr_raises(self):
        class MySeq(collections.abc.Sequence):
            def __init__(self, raises):

diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-03-19-01-19-34.gh-issue-146096.R9tkJX.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-03-19-01-19-34.gh-issue-146096.R9tkJX.rst
@@ -0,0 +1,2 @@
+Fixed segmentation fault when called repr for BaseExceptionGroup with empty
+or 1-size tuple args.
@@ -1091,7 +1091,8 @@ BaseExceptionGroup_repr(PyObject *op)
         * value of self.args[1]; but this can be mutable and go out-of-sync
         * with self.exceptions. Instead, use self.exceptions for accuracy,
         * making it look like self.args[1] for backwards compatibility. */
-        if (PyList_Check(PyTuple_GET_ITEM(self->args, 1))) {
+        assert(PyTuple_Check(self->args));
+        if (PyTuple_GET_SIZE(self->args) == 2 && PyList_Check(PyTuple_GET_ITEM(self->args, 1))) {
            PyObject *exceptions_list = PySequence_List(self->excs);
            if (!exceptions_list) {
                return NULL;
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Fixed segmentation fault when called repr for BaseExceptionGroup with empty
		or 1-size tuple args.
-Original file line number
+Diff line change
@@ -1091,7 +1091,8 @@ BaseExceptionGroup_repr(PyObject *op)
              * value of self.args[1]; but this can be mutable and go out-of-sync
              * with self.exceptions. Instead, use self.exceptions for accuracy,
              * making it look like self.args[1] for backwards compatibility. */
-            if (PyList_Check(PyTuple_GET_ITEM(self->args, 1))) {
+            assert(PyTuple_Check(self->args));
+            if (PyTuple_GET_SIZE(self->args) == 2 && PyList_Check(PyTuple_GET_ITEM(self->args, 1))) {
         Comment thread


        

        
      

        
          


  
    
        
        
  
    
      
          
      

      
            iritkatriel
  

      

      

      


        Mar 18, 2026



      
    

  

  
    
      
          
    
  


        
            
  
      
              Copy link

  
              
  
      
                Copy Markdown

  
        
      
    

    
        

  
  Member


        

    
  


        
      
  
  
  
    

    There was a problem hiding this comment.


  

 
  
    

    Choose a reason for hiding this comment

    
      The reason will be displayed to describe this comment to others. Learn more.
    

    
      
      


  


  
    
      Do we need to check that it's a Tuple first?
    
  
  



    

        
      
  
  
    
  
  
  
    
    Sorry, something went wrong.
  

  
    
  
    
      

              Uh oh!

              
There was an error while loading. Please reload this page.


  
  


          
              
  
    
    
      
        
            
    All reactions
  


          
          
        
      
    


      



    
        
  
    
      
          
      

      
            dr-carlos
  

      

      

      


        Mar 18, 2026



      
    

  

  
    
      
          
    
  


        
            
  
      
              Copy link

  
              
  
      
                Copy Markdown

  
        
      
    

    
        

  
    Contributor


        

    
  


        
      
  
  
  
    

    There was a problem hiding this comment.


  

 
  
    

    Choose a reason for hiding this comment

    
      The reason will be displayed to describe this comment to others. Learn more.
    

    
      
      


  


  
    
      No, args is always converted to a tuple in its setter:

https://github.com/sergey-miryanov/cpython/blob/4f9a6ba7ba98a83d5594aacadcddb90696ffd5d7/Objects/exceptions.c#L351-L364
    
  
  



    

        
      
  
  
    
  
  
  
    
    Sorry, something went wrong.
  

  
    
  
    
      

              Uh oh!

              
There was an error while loading. Please reload this page.


  
  


          
              
  
    
    
      
        
            
    All reactions
  


          
          
        
      
    


      



    
        
  
    
      
          
      

      
            iritkatriel
  

      

      

      


        Mar 19, 2026



      
    

  

  
    
      
          
    
  


        
            
  
      
              Copy link

  
              
  
      
                Copy Markdown

  
        
      
    

    
        

  
  Member


        

    
  


        
      
  
  
  
    

    There was a problem hiding this comment.


  

 
  
    

    Choose a reason for hiding this comment

    
      The reason will be displayed to describe this comment to others. Learn more.
    

    
      
      


  


  
    
      Could add an assert just so it reads like it makes sense.
    
  
  



    

        
      
  
  
    
  
  
  
    
    Sorry, something went wrong.
  

  
    
  
    
      

              Uh oh!

              
There was an error while loading. Please reload this page.


  
  


          
              
  
    
    
      
        
            
    All reactions
  


          
          
        
      
    


      



    
        
  
    
      
          
      

      
            sergey-miryanov
  

      

      

      


        Mar 19, 2026



      
    

  

  
    
      
          
    
  


        
            
  
      
              Copy link

  
              
  
      
                Copy Markdown

  
        
      
    

    
        

  
    Contributor


        

  Author


    
  


        
      
  
  
  
    

    There was a problem hiding this comment.


  

 
  
    

    Choose a reason for hiding this comment

    
      The reason will be displayed to describe this comment to others. Learn more.
    

    
      
      


  


  
    
      Done
    
  
  



    

        
      
  
  
    
  
  
  
    
    Sorry, something went wrong.
  

  
    
  
    
      

              Uh oh!

              
There was an error while loading. Please reload this page.


  
  


          
              
  
    
    
            iritkatriel reacted with thumbs up emoji
      
        
            
    All reactions
  


          
              
                👍
                  1 reaction
                 PyObject *exceptions_list = PySequence_List(self->excs);
                 if (!exceptions_list) {
                     return NULL;
-          Expand Down