## Summary
This PR partially solves https://github.com/astral-sh/ty/issues/164
(derived from #17643).
Currently, the definitions we manage are limited to those for simple
name (symbol) targets, but we expand this to track definitions for
attribute and subscript targets as well.
This was originally planned as part of the work in #17643, but the
changes are significant, so I made it a separate PR.
After merging this PR, I will reflect this changes in #17643.
There is still some incomplete work remaining, but the basic features
have been implemented, so I am publishing it as a draft PR.
Here is the TODO list (there may be more to come):
* [x] Complete rewrite and refactoring of documentation (removing
`Symbol` and replacing it with `Place`)
* [x] More thorough testing
* [x] Consolidation of duplicated code (maybe we can consolidate the
handling related to name, attribute, and subscript)
This PR replaces the current `Symbol` API with the `Place` API, which is
a concept that includes attributes and subscripts (the term is borrowed
from Rust).
## Test Plan
`mdtest/narrow/assignment.md` is added.
---------
Co-authored-by: David Peter <sharkdp@users.noreply.github.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
With this PR we now detect that x is always defined in `use`:
```py
if flag and (x := number):
use(x)
```
When outside if, it's still detected as possibly not defined
```py
flag and (x := number)
# error: [possibly-unresolved-reference]
use(x)
```
In order to achieve that, I had to find a way to get access to the
flow-snapshots of the boolean expression when analyzing the flow of the
if statement. I did it by special casing the visitor of boolean
expression to return flow control information, exporting two snapshots -
`maybe_short_circuit` and `no_short_circuit`. When indexing
boolean expression itself we must assume all possible flows, but when
it's inside if statement, we can be smarter than that.
## Test Plan
Fixed existing and added new mdtests.
I went through some of mypy primer results and they look fine
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This PR fixes#17595.
## Test Plan
New test cases are added to `mdtest/narrow/conditionals/nested.md`.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Shunsuke Shibayama
Alex Waygood
Carl Meyer
TomerBin
Charlie Marsh
Micha Reiser