62 lines
2 KiB
Python
62 lines
2 KiB
Python
|
"""
|
||
|
|
This is a module for various lookup functions:
|
||
|
|
functions that will find a semantic node by its name.
|
||
|
|
"""
|
||
|
|
|
||
|
|
from __future__ import annotations
|
||
|
|
|
||
|
|
from mypy.nodes import MypyFile, SymbolTableNode, TypeInfo
|
||
|
|
|
||
|
|
# TODO: gradually move existing lookup functions to this module.
|
||
|
|
|
||
|
|
|
||
|
|
def lookup_fully_qualified(
|
||
|
|
name: str, modules: dict[str, MypyFile], *, raise_on_missing: bool = False
|
||
|
|
) -> SymbolTableNode | None:
|
||
|
|
"""Find a symbol using it fully qualified name.
|
||
|
|
|
||
|
|
The algorithm has two steps: first we try splitting the name on '.' to find
|
||
|
|
the module, then iteratively look for each next chunk after a '.' (e.g. for
|
||
|
|
nested classes).
|
||
|
|
|
||
|
|
This function should *not* be used to find a module. Those should be looked
|
||
|
|
in the modules dictionary.
|
||
|
|
"""
|
||
|
|
head = name
|
||
|
|
rest = []
|
||
|
|
# 1. Find a module tree in modules dictionary.
|
||
|
|
while True:
|
||
|
|
if "." not in head:
|
||
|
|
if raise_on_missing:
|
||
|
|
assert "." in head, f"Cannot find module for {name}"
|
||
|
|
return None
|
||
|
|
head, tail = head.rsplit(".", maxsplit=1)
|
||
|
|
rest.append(tail)
|
||
|
|
mod = modules.get(head)
|
||
|
|
if mod is not None:
|
||
|
|
break
|
||
|
|
names = mod.names
|
||
|
|
# 2. Find the symbol in the module tree.
|
||
|
|
if not rest:
|
||
|
|
# Looks like a module, don't use this to avoid confusions.
|
||
|
|
if raise_on_missing:
|
||
|
|
assert rest, f"Cannot find {name}, got a module symbol"
|
||
|
|
return None
|
||
|
|
while True:
|
||
|
|
key = rest.pop()
|
||
|
|
if key not in names:
|
||
|
|
if raise_on_missing:
|
||
|
|
assert key in names, f"Cannot find component {key!r} for {name!r}"
|
||
|
|
return None
|
||
|
|
stnode = names[key]
|
||
|
|
if not rest:
|
||
|
|
return stnode
|
||
|
|
node = stnode.node
|
||
|
|
# In fine-grained mode, could be a cross-reference to a deleted module
|
||
|
|
# or a Var made up for a missing module.
|
||
|
|
if not isinstance(node, TypeInfo):
|
||
|
|
if raise_on_missing:
|
||
|
|
assert node, f"Cannot find {name}"
|
||
|
|
return None
|
||
|
|
names = node.names
|