pytorch

bcd77cec - [JIT] Display an error message when with item is not an object (#52335)

[JIT] Display an error message when with item is not an object (#52335) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/52335 **Summary** `with` statements can only be used with objects that have `__enter__` and `__exit__` defined. At present, any attempt to use an expression that returns something that is not an instance of a class type results in a cryptic internal assert failure instead of a useful error message. This is because the code that generates IR for `with` statements uses `Type::expect` as if it were `Type::cast`; that is, as if it returns `nullptr` on failure. This commit fixes this issue by checking the `kind()` of the type of the expression used as the with item before calling `expect<ClassType>()` on it. **Test Plan** This commit adds a unit test to `test_with_errors` to test this case. Test Plan: Imported from OSS Reviewed By: gmagogsfm Differential Revision: D26504909 Pulled By: SplitInfinity fbshipit-source-id: 92d108e0c010370fd45131a57120f50c0b85c401