Internal error with mypy 0.720's new semantic analyzer

[scop]

I'm seeing internal errors with mypy 0.720's new semantic analyzer. No minimal reproducer yet, but perhaps you can make some sense of the traceback alone:

$ mypy --show-traceback fixtures.py 
fixtures.py:55: error: INTERNAL ERROR -- Please try using mypy master on Github:
https://mypy.rtfd.io/en/latest/common_issues.html#using-a-development-mypy-build
Please report a bug at https://github.com/python/mypy/issues
version: 0.720
Traceback (most recent call last):
  File "mypy/checkexpr.py", line 3404, in accept
  File "mypy/nodes.py", line 1527, in accept
  File "mypy/checkexpr.py", line 234, in visit_call_expr__ExpressionVisitor_glue
  File "mypy/checkexpr.py", line 243, in visit_call_expr
  File "mypy/checkexpr.py", line 315, in visit_call_expr_inner
  File "mypy/checkexpr.py", line 670, in check_call_expr_with_callee_type
  File "mypy/checkexpr.py", line 728, in check_call
  File "mypy/checkexpr.py", line 835, in check_callable_call
  File "mypy/checkexpr.py", line 573, in apply_function_plugin
  File ".../lib/python3.7/site-packages/mypy_django_plugin/transformers/init_create.py", line 27, in redefine_and_typecheck_model_init
    expected_types = extract_expected_types(ctx, model, is_init=True)
  File ".../lib/python3.7/site-packages/mypy_django_plugin/transformers/init_create.py", line 163, in extract_expected_types
    autofield_info = api.lookup_typeinfo('django.db.models.fields.AutoField')
  File "mypy/checker.py", line 3721, in lookup_typeinfo
  File "mypy/checker.py", line 3772, in lookup_qualified
AssertionError: Internal error: attempted lookup of unknown name
fixtures.py:55: : note: use --pdb to drop into pdb

Same thing with current django-stubs master.

Running mypy with the --no-new-semantic-analyzer flag works around it for now, but that flag is going away soon.

[mkurnikov]

This is a big rewrite incoming, which will be using Django's AppRegistry and new semantic analyzer, should be out in a week or so. Stay tuned, all those issues should be fixed there.