SQLite SchemaEditor crashes when adding a ForeignObject field

[Tim Graham]

Adding a ForeignObject field to an existing model will fail like this on SQLite:

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ERROR: test_add_foreign_object (schema.tests.SchemaTests)
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Traceback (most recent call last):
  File "/home/tim/code/django/tests/schema/tests.py", line 1518, in test_add_foreign_object
    editor.add_field(BookForeignObj, new_field)
  File "/home/tim/code/django/django/db/backends/sqlite3/schema.py", line 221, in add_field
    self._remake_table(model, create_fields=[field])
  File "/home/tim/code/django/django/db/backends/sqlite3/schema.py", line 187, in _remake_table
    ', '.join(self.quote_name(x) for x, y in field_maps),
  File "/home/tim/code/django/django/db/backends/sqlite3/schema.py", line 187, in <genexpr>
    ', '.join(self.quote_name(x) for x, y in field_maps),
  File "/home/tim/code/django/django/db/backends/base/schema.py", line 113, in quote_name
    return self.connection.ops.quote_name(name)
  File "/home/tim/code/django/django/db/backends/sqlite3/operations.py", line 107, in quote_name
    if name.startswith('"') and name.endswith('"'):
AttributeError: 'NoneType' object has no attribute 'startswith'

[Tim Graham]

​PR

[Tim Graham <timograham@…>]

In c52822e:

Fixed #25128 -- Fixed SQLite SchemaEditor crash when adding a ForeignObject field.