Crash TypeError: unhashable type: 'list' for view-only users

[phihag]

If a user without change permissions but with view permissions visits a change page with a CountryField, it crashes:

Traceback (most recent call last):                                                                                                                                          
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/core/handlers/exception.py", line 34, in inner                            
    response = get_response(request)                                                                                                                                        
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/core/handlers/base.py", line 145, in _get_response                        
    response = self.process_exception_by_middleware(e, request)                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/core/handlers/base.py", line 143, in _get_response                        
    response = response.render()                                                                                                                                            
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/response.py", line 106, in render                                
    self.content = self.rendered_content                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/response.py", line 83, in rendered_content                       
    content = template.render(context, self._request)                                                                                                                       
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/backends/django.py", line 61, in render                          
    return self.template.render(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 171, in render                                    
    return self._render(context)                                                                                                                                            
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/test/utils.py", line 96, in instrumented_test_render                      
    return self.nodelist.render(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/loader_tags.py", line 150, in render                             
    return compiled_parent._render(context)                                                                                                                                 
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/test/utils.py", line 96, in instrumented_test_render                      
    return self.nodelist.render(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/loader_tags.py", line 150, in render                             
    return compiled_parent._render(context)                                                                                                                                 
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/test/utils.py", line 96, in instrumented_test_render                      
    return self.nodelist.render(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/loader_tags.py", line 62, in render                              
    result = block.nodelist.render(context)                                                                                                                                 
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/loader_tags.py", line 62, in render                              
    result = block.nodelist.render(context)                                                                                                                                 
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 209, in render                             
    nodelist.append(node.render_annotated(context))                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/loader_tags.py", line 188, in render                             
    return template.render(context)                                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 173, in render                                    
    return self._render(context)                                                                                                                                            
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/test/utils.py", line 96, in instrumented_test_render                      
    return self.nodelist.render(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render                                    
    bit = node.render_annotated(context)                                                                                                                                    
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 209, in render                             
    nodelist.append(node.render_annotated(context))                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 209, in render                             
    nodelist.append(node.render_annotated(context))                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 209, in render                             
    nodelist.append(node.render_annotated(context))                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 209, in render                             
    nodelist.append(node.render_annotated(context))                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated                          
    return self.render(context)                                                                                                                                             
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 309, in render                             
    return nodelist.render(context)                                                                                                                                         
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render
    bit = node.render_annotated(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated
    return self.render(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/defaulttags.py", line 309, in render
    return nodelist.render(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 937, in render
    bit = node.render_annotated(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 904, in render_annotated
    return self.render(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 987, in render
    output = self.filter_expression.resolve(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 671, in resolve
    obj = self.var.resolve(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 796, in resolve
    value = self._resolve_lookup(context)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/template/base.py", line 858, in _resolve_lookup
    current = current()
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/contrib/admin/helpers.py", line 218, in contents
    result_repr = display_for_field(value, f, self.empty_value_display)
  File "/home/phihag/.local/share/virtualenvs/octonie-vqgHbSx7/lib/python3.8/site-packages/django/contrib/admin/utils.py", line 382, in display_for_field
    return dict(field.flatchoices).get(value, empty_value_display)
TypeError: unhashable type: 'list'

The problem is that value is something like [Country(code='BE'), Country(code='CA')]. I'm not sure this can be solved in plain Django, because the render path does not seem to have a read-only rendering. See also https://code.djangoproject.com/ticket/30577

[jedie]

It's the same as #311 isn't it?

[SmileyChris]

Yeah, duplicate.