gh-116608: importlib.resources: Un-deprecate functional API & add subdirectory support (GH-116609)

1 files changed, 85 insertions, 0 deletions

diff --git a/Lib/importlib/resources/_functional.py b/Lib/importlib/resources/_functional.py
new file mode 100644
index 00000000000..9e3ea1547d4
--- /dev/null
+++ b/Lib/importlib/resources/_functional.py
@@ -0,0 +1,85 @@
+"""Simplified function-based API for importlib.resources"""
+
+import warnings
+
+from ._common import files, as_file
+
+
+_MISSING = object()
+
+
+def open_binary(anchor, *path_names):
+    """Open for binary reading the *resource* within *package*."""
+    return _get_resource(anchor, path_names).open('rb')
+
+
+def open_text(anchor, *path_names, encoding=_MISSING, errors='strict'):
+    """Open for text reading the *resource* within *package*."""
+    encoding = _get_encoding_arg(path_names, encoding)
+    resource = _get_resource(anchor, path_names)
+    return resource.open('r', encoding=encoding, errors=errors)
+
+
+def read_binary(anchor, *path_names):
+    """Read and return contents of *resource* within *package* as bytes."""
+    return _get_resource(anchor, path_names).read_bytes()
+
+
+def read_text(anchor, *path_names, encoding=_MISSING, errors='strict'):
+    """Read and return contents of *resource* within *package* as str."""
+    encoding = _get_encoding_arg(path_names, encoding)
+    resource = _get_resource(anchor, path_names)
+    return resource.read_text(encoding=encoding, errors=errors)
+
+
+def path(anchor, *path_names):
+    """Return the path to the *resource* as an actual file system path."""
+    return as_file(_get_resource(anchor, path_names))
+
+
+def is_resource(anchor, *path_names):
+    """Return ``True`` if there is a resource named *name* in the package,
+
+    Otherwise returns ``False``.
+    """
+    return _get_resource(anchor, path_names).is_file()
+
+
+def contents(anchor, *path_names):
+    """Return an iterable over the named resources within the package.
+
+    The iterable returns :class:`str` resources (e.g. files).
+    The iterable does not recurse into subdirectories.
+    """
+    warnings.warn(
+        "importlib.resources.contents is deprecated. "
+        "Use files(anchor).iterdir() instead.",
+        DeprecationWarning,
+        stacklevel=1,
+    )
+    return (
+        resource.name
+        for resource
+        in _get_resource(anchor, path_names).iterdir()
+    )
+
+
+def _get_encoding_arg(path_names, encoding):
+    # For compatibility with versions where *encoding* was a positional
+    # argument, it needs to be given explicitly when there are multiple
+    # *path_names*.
+    # This limitation can be removed in Python 3.15.
+    if encoding is _MISSING:
+        if len(path_names) > 1:
+            raise TypeError(
+                "'encoding' argument required with multiple path names",
+            )
+        else:
+            return 'utf-8'
+    return encoding
+
+
+def _get_resource(anchor, path_names):
+    if anchor is None:
+        raise TypeError("anchor must be module or string, got None")
+    return files(anchor).joinpath(*path_names)