bug: Mypy crashes upon using class-constructor with named-tuple

[savil]

Please provide more information to help us understand the issue:

• Are you reporting a bug, or opening a feature request?

A bug

• Please insert below the code you are checking with mypy,
  or a mock-up repro if the source is private. We would appreciate
  if you try to simplify your case to a minimal repro.

code:

$ cat src/main.py

from typing import NamedTuple, Type, TypeVar

class NodeDataTuple(NamedTuple):
    created: int
    updated: int

T = TypeVar('T', bound=NodeDataTuple)
class Node():
    def __init__(self, data_constructor: Type[T]) -> None:
        my_dict = {"foo": "bar"}
        self._data = data_constructor(**my_dict)

• What is the actual behavior/output?

src/main.py:11: error: INTERNAL ERROR -- please report a bug at https://github.com/python/mypy/issues version: 0.670
src/main.py:11: : note: please use --show-traceback to print a traceback when reporting a bug

• What is the behavior/output you expect?

don't crash

• What are the versions of mypy and Python you are using?
  Do you see the same issue after installing mypy from Git master?

Environment (Mac OSX 10.14.3, in a virtualenv):
$ python --version
Python 3.7.2
$ mypy --version
mypy 0.670

Also, tried with latest git mypy version: 0.680+dev.892b8d85afb80c9833248f2a8acf1c65023e0cad

• What are the mypy flags you are using? (For example --strict-optional)

none, no config file either

• If mypy crashed with a traceback, please paste
  the full traceback below.

Traceback (most recent call last):
  File "/Users/savil/code/mypy-debug/venv/bin/mypy", line 10, in <module>
    sys.exit(console_entry())
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/__main__.py", line 7, in console_entry
    main(None)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/main.py", line 91, in main
    res = build.build(sources, options, None, flush_errors, fscache)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 162, in build
    result = _build(sources, options, alt_lib_path, flush_errors, fscache)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 217, in _build
    graph = dispatch(sources, manager)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 2360, in dispatch
    process_graph(graph, manager)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 2660, in process_graph
    process_stale_scc(graph, scc, manager)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 2767, in process_stale_scc
    graph[id].type_check_first_pass()
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/build.py", line 1919, in type_check_first_pass
    self.type_checker().check_first_pass()
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 282, in check_first_pass
    self.accept(d)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 393, in accept
    stmt.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 846, in accept
    return visitor.visit_class_def(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 1537, in visit_class_def
    self.accept(defn.defs)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 393, in accept
    stmt.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 911, in accept
    return visitor.visit_block(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 1701, in visit_block
    self.accept(s)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 393, in accept
    stmt.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 606, in accept
    return visitor.visit_func_def(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 704, in visit_func_def
    self._visit_func_def(defn)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 708, in _visit_func_def
    self.check_func_item(defn, name=defn.name())
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 770, in check_func_item
    self.check_func_def(defn, typ, name)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 932, in check_func_def
    self.accept(item.body)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 393, in accept
    stmt.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 911, in accept
    return visitor.visit_block(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 1701, in visit_block
    self.accept(s)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 393, in accept
    stmt.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 969, in accept
    return visitor.visit_assignment_stmt(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 1709, in visit_assignment_stmt
    self.check_assignment(s.lvalues[-1], s.rvalue, s.type is None, s.new_syntax)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checker.py", line 1828, in check_assignment
    in_final_declaration=inferred.is_final,
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 3188, in accept
    typ = node.accept(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/nodes.py", line 1446, in accept
    return visitor.visit_call_expr(self)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 244, in visit_call_expr
    return self.visit_call_expr_inner(e, allow_none_return=allow_none_return)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 314, in visit_call_expr_inner
    ret_type = self.check_call_expr_with_callee_type(callee_type, e, fullname, object_type)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 658, in check_call_expr_with_callee_type
    object_type=object_type)[0]
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 721, in check_call
    callable_node, arg_messages)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 695, in check_call
    object_type)
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/checkexpr.py", line 753, in check_callable_call
    if (callee.is_type_obj() and callee.type_object().is_abstract
  File "/Users/savil/code/mypy-debug/venv/lib/python3.7/site-packages/mypy/types.py", line 925, in type_object
    assert isinstance(ret, Instance)
AssertionError:
src/main.py:11: : note: use --pdb to drop into pdb

[ilevkivskyi]

I think this should be prohibited, since this is essentially the same as #6520. (cc @msullivan)

But in any case we should not crash.

[onlined]

On master, this doesn't crash anymore, after #6669 I suppose.
Instead, it gives an error:
test.py:11: error: Argument 1 to "NodeDataTuple" has incompatible type "**Dict[str, str]"; expected "int"
Is this a problem?

[ilevkivskyi]

OK, this can be closed then. The rest is tracked in #5382 and #6520.