Pass root path to FullyQualifiedNameProvider (#867)

This allows FullyQualifiedNameProvider to work with absolute paths,
rather than assuming all paths given will be relative to the current
directory. This enables tools like Fixit to provide a root path, and
have the FullyQualifiedNameProvider correctly scope the final results
relative to that root path.

This does require that both the root path and the given file paths
match the other as relative or absolute, due to the
`calculate_module_and_package` helper comparing file paths relative
to the root path, but this seems like a reasonable tradeoff, and
unlikely to cause a problem in normal use cases.

libcst/_types.py

@@ -4,7 +4,8 @@
 # LICENSE file in the root directory of this source tree.
 
 
-from typing import TYPE_CHECKING, TypeVar
+from pathlib import PurePath
+from typing import TYPE_CHECKING, TypeVar, Union
 
 if TYPE_CHECKING:
     from libcst._nodes.base import CSTNode  # noqa: F401
@@ -12,3 +13,4 @@ if TYPE_CHECKING:
 
 CSTNodeT = TypeVar("CSTNodeT", bound="CSTNode")
 CSTNodeT_co = TypeVar("CSTNodeT_co", bound="CSTNode", covariant=True)
+StrPath = Union[str, PurePath]

libcst/helpers/module.py

@@ -9,6 +9,7 @@ from pathlib import PurePath
 from typing import List, Optional
 
 from libcst import Comment, EmptyLine, ImportFrom, Module
+from libcst._types import StrPath
 from libcst.helpers.expression import get_full_name_for_node
 
 
@@ -130,7 +131,9 @@ class ModuleNameAndPackage:
     package: str
 
 
-def calculate_module_and_package(repo_root: str, filename: str) -> ModuleNameAndPackage:
+def calculate_module_and_package(
+    repo_root: StrPath, filename: StrPath
+) -> ModuleNameAndPackage:
     # Given an absolute repo_root and an absolute filename, calculate the
     # python module name for the file.
     relative_filename = PurePath(filename).relative_to(repo_root)

libcst/metadata/full_repo_manager.py

@@ -8,6 +8,7 @@ from pathlib import Path
 from typing import Collection, Dict, List, Mapping, TYPE_CHECKING
 
 import libcst as cst
+from libcst._types import StrPath
 from libcst.metadata.wrapper import MetadataWrapper
 
 if TYPE_CHECKING:
@@ -17,7 +18,7 @@ if TYPE_CHECKING:
 class FullRepoManager:
     def __init__(
         self,
-        repo_root_dir: str,
+        repo_root_dir: StrPath,
         paths: Collection[str],
         providers: Collection["ProviderT"],
         timeout: int = 5,

libcst/metadata/name_provider.py

@@ -114,7 +114,7 @@ class FullyQualifiedNameProvider(BatchableMetadataProvider[Collection[QualifiedN
     def gen_cache(
         cls, root_path: Path, paths: List[str], timeout: Optional[int] = None
     ) -> Mapping[str, ModuleNameAndPackage]:
-        cache = {path: calculate_module_and_package(".", path) for path in paths}
+        cache = {path: calculate_module_and_package(root_path, path) for path in paths}
         return cache
 
     def __init__(self, cache: ModuleNameAndPackage) -> None:

libcst/metadata/tests/test_name_provider.py

@@ -560,11 +560,14 @@ class FullyQualifiedNameProviderTest(UnitTest):
 class FullyQualifiedNameIntegrationTest(UnitTest):
     def test_with_full_repo_manager(self) -> None:
         with TemporaryDirectory() as dir:
-            fname = "pkg/mod.py"
-            (Path(dir) / "pkg").mkdir()
-            (Path(dir) / fname).touch()
-            mgr = FullRepoManager(dir, [fname], [FullyQualifiedNameProvider])
-            wrapper = mgr.get_metadata_wrapper_for_path(fname)
+            root = Path(dir)
+            file_path = root / "pkg/mod.py"
+            file_path.parent.mkdir()
+            file_path.touch()
+
+            file_path_str = file_path.as_posix()
+            mgr = FullRepoManager(root, [file_path_str], [FullyQualifiedNameProvider])
+            wrapper = mgr.get_metadata_wrapper_for_path(file_path_str)
             fqnames = wrapper.resolve(FullyQualifiedNameProvider)
             (mod, names) = next(iter(fqnames.items()))
             self.assertIsInstance(mod, cst.Module)