Succeed even if there are unsupported node types, but report error in output JSON

Also add tests.

Author: JukkaL

mypy/exportjson.py

@@ -152,7 +152,7 @@ def convert_symbol_node(self: SymbolNode, cfg: Config) -> Json:
         return convert_param_spec_expr(self)
     elif isinstance(self, TypeVarTupleExpr):
         return convert_type_var_tuple_expr(self)
-    assert False, type(self)
+    return {"ERROR": f"{type(self)!r} unrecognized"}
 
 
 def convert_func_def(self: FuncDef) -> Json:
@@ -364,7 +364,7 @@ def convert_type(typ: Type) -> Json:
         return convert_typeddict_type(typ)
     elif isinstance(typ, UnboundType):
         return convert_unbound_type(typ)
-    assert False, type(typ)
+    return {"ERROR": f"{type(typ)!r} unrecognized"}
 
 
 def convert_instance(self: Instance) -> Json:

mypy/test/testexportjson.py

@@ -59,6 +59,7 @@ def run_case(self, testcase: DataDrivenTestCase) -> None:
                     if '"path": ' in line:
                         # We source file path is unpredictable, so filter it out
                         line = re.sub(r'"[^"]+\.pyi?"', "...", line)
+                    assert "ERROR" not in line, line
                     a.append(line)
         except CompileError as e:
             a = e.messages

test-data/unit/exportjson.test

@@ -193,7 +193,7 @@ def foo(a: int) -> None: ...
 [case testExportDifferentTypes]
 from __future__ import annotations
 
-from typing import Callable, Any, Literal, NoReturn
+from typing import Callable, Any, Literal, NoReturn, TypedDict, NamedTuple
 
 list_ann: list[int]
 any_ann: Any
@@ -209,7 +209,17 @@ def f() -> NoReturn:
 BadType = 1
 x: BadType  # type: ignore
 
+class TD(TypedDict):
+    x: int
+
+td = TD(x=1)
+
+NT = NamedTuple("NT", [("x", int)])
+
+nt = NT(x=1)
+
 [builtins fixtures/tuple.pyi]
+[typing fixtures/typing-medium.pyi]
 [out]
 <not checked>