Exception: Cache is required for initializing FullyQualifiedNameProvider.

[nschloe]

I'm trying to figure out how to use the FullyQualifiedNameProvider. This

import libcst as cst
from libcst.metadata import FullyQualifiedNameProvider, MetadataWrapper


class FullyQualifiedNameCollector(cst.CSTVisitor):
    METADATA_DEPENDENCIES = (FullyQualifiedNameProvider,)

    def visit_Name(self, node: cst.Name) -> None:
        fqns = self.get_metadata(FullyQualifiedNameProvider, node, None)
        if fqns:
            for fqn in fqns:
                print(f"Identifier: {node.value}, Fully Qualified Name: {fqn.name}")


code = """
import os

def my_function():
    print(os.path.join("a", "b"))
"""

module = cst.parse_module(code)
wrapper = MetadataWrapper(module)

collector = FullyQualifiedNameCollector()
wrapper.visit(collector)

gives

Exception: Cache is required for initializing FullyQualifiedNameProvider.

Any hints?

[obiwac]

You need to use FullRepoManager. Look at the example for FullyQualifiedNameProvider here. FullyQualifiedNameProvider needs the context of your codebase to be able to provide you with fully qualfiied names.