refactor select_value and select_node out of OmegaConf.select

omegaconf/_impl.py

@@ -1,7 +1,9 @@
 from typing import Any
 
 from omegaconf import MISSING, Container, DictConfig, ListConfig, Node, ValueNode
-from omegaconf.errors import InterpolationToMissingValueError
+from omegaconf.errors import ConfigKeyError, InterpolationToMissingValueError
+
+from ._utils import _DEFAULT_MARKER_, _get_value
 
 
 def _resolve_container_value(cfg: Container, key: Any) -> None:
@@ -42,3 +44,68 @@ def _resolve(cfg: Node) -> Node:
             _resolve_container_value(cfg, i)
 
     return cfg
+
+
+def select_value(
+    cfg: Container,
+    key: str,
+    *,
+    default: Any = _DEFAULT_MARKER_,
+    throw_on_resolution_failure: bool = True,
+    throw_on_missing: bool = False,
+    absolute_key: bool = False,
+) -> Any:
+    ret = select_node(
+        cfg=cfg,
+        key=key,
+        default=default,
+        throw_on_resolution_failure=throw_on_resolution_failure,
+        throw_on_missing=throw_on_missing,
+        absolute_key=absolute_key,
+    )
+    if isinstance(ret, Node) and ret._is_missing():
+        return None
+
+    return _get_value(ret)
+
+
+def select_node(
+    cfg: Container,
+    key: str,
+    *,
+    default: Any = _DEFAULT_MARKER_,
+    throw_on_resolution_failure: bool = True,
+    throw_on_missing: bool = False,
+    absolute_key: bool = False,
+) -> Any:
+    try:
+        # for non relative keys, the interpretation can be:
+        # 1. relative to cfg
+        # 2. relative to the config root
+        # This is controlled by the absolute_key flag. By default, such keys are relative to cfg.
+        if not absolute_key and not key.startswith("."):
+            key = f".{key}"
+
+        cfg, key = cfg._resolve_key_and_root(key)
+        _root, _last_key, value = cfg._select_impl(
+            key,
+            throw_on_missing=throw_on_missing,
+            throw_on_resolution_failure=throw_on_resolution_failure,
+        )
+    except ConfigKeyError:
+        if default is not _DEFAULT_MARKER_:
+            return default
+        else:
+            raise
+
+    if (
+        default is not _DEFAULT_MARKER_
+        and _root is not None
+        and _last_key is not None
+        and _last_key not in _root
+    ):
+        return default
+
+    if value is not None and value._is_missing():
+        return None
+    return value

omegaconf/omegaconf.py

@@ -30,7 +30,6 @@
 from ._utils import (
     _DEFAULT_MARKER_,
     _ensure_container,
-    _get_value,
     _is_none,
     format_and_raise,
     get_dict_key_value_types,
@@ -53,7 +52,6 @@
 from .base import Container, Node, SCMode
 from .basecontainer import BaseContainer
 from .errors import (
-    ConfigKeyError,
     MissingMandatoryValue,
     OmegaConfBaseException,
     UnsupportedInterpolationType,
@@ -653,7 +651,6 @@ def select(
         default: Any = _DEFAULT_MARKER_,
         throw_on_resolution_failure: bool = True,
         throw_on_missing: bool = False,
-        absolute_key: bool = False,
     ) -> Any:
         """
         :param cfg: Config node to select from
@@ -663,43 +660,18 @@ def select(
                resolution error occurs, otherwise return None
         :param throw_on_missing: Raise an exception if an attempt to select a missing key (with the value '???')
                is made, otherwise return None
-        :param absolute_key: True to treat non-relative keys as relative to the config root
-                             False (default) to treat non-relative keys as relative to cfg
         :return: selected value or None if not found.
         """
-        try:
-            try:
-                # for non relative keys, the interpretation can be:
-                # 1. relative to cfg
-                # 2. relative to the config root
-                # This is controlled by the absolute_key flag. By default, such keys are relative to cfg.
-                if not absolute_key and not key.startswith("."):
-                    key = f".{key}"
-
-                cfg, key = cfg._resolve_key_and_root(key)
-                _root, _last_key, value = cfg._select_impl(
-                    key,
-                    throw_on_missing=throw_on_missing,
-                    throw_on_resolution_failure=throw_on_resolution_failure,
-                )
-            except ConfigKeyError:
-                if default is not _DEFAULT_MARKER_:
-                    return default
-                else:
-                    raise
-
-            if (
-                default is not _DEFAULT_MARKER_
-                and _root is not None
-                and _last_key is not None
-                and _last_key not in _root
-            ):
-                return default
+        from ._impl import select_value
 
-            if value is not None and value._is_missing():
-                return None
-
-            return _get_value(value)
+        try:
+            return select_value(
+                cfg=cfg,
+                key=key,
+                default=default,
+                throw_on_resolution_failure=throw_on_resolution_failure,
+                throw_on_missing=throw_on_missing,
+            )
         except Exception as e:
             format_and_raise(node=cfg, key=key, value=None, cause=e, msg=str(e))
 

omegaconf/resolvers/oc/dict.py

@@ -53,15 +53,15 @@ def _get_and_validate_dict_input(
     parent: BaseContainer,
     resolver_name: str,
 ) -> DictConfig:
-    from omegaconf import OmegaConf
+    from omegaconf._impl import select_value
 
     if not isinstance(key, str):
         raise TypeError(
             f"`{resolver_name}` requires a string as input, but obtained `{key}` "
             f"of type: {type(key).__name__}"
         )
 
-    in_dict = OmegaConf.select(
+    in_dict = select_value(
         parent,
         key,
         throw_on_missing=True,

tests/test_select.py

@@ -5,6 +5,7 @@
 from pytest import mark, param, raises
 
 from omegaconf import MissingMandatoryValue, OmegaConf
+from omegaconf._impl import select_value
 from omegaconf._utils import _ensure_container
 from omegaconf.errors import ConfigKeyError, InterpolationKeyError
 
@@ -265,8 +266,8 @@ def test_select_from_nested_node_with_a_relative_key(
     ) -> None:
         cfg = OmegaConf.create(inp)
         # select returns the same result when a key is relative independent of absolute_key flag.
-        assert OmegaConf.select(cfg.a, key, absolute_key=False) == expected
-        assert OmegaConf.select(cfg.a, key, absolute_key=True) == expected
+        assert select_value(cfg.a, key, absolute_key=False) == expected
+        assert select_value(cfg.a, key, absolute_key=True) == expected
 
     @mark.parametrize(
         ("key", "expected"),
@@ -282,7 +283,7 @@ def test_select_from_nested_node_relative_key_interpretation(
         self, key: str, expected: Any
     ) -> None:
         cfg = OmegaConf.create(inp)
-        assert OmegaConf.select(cfg.a, key, absolute_key=False) == expected
+        assert select_value(cfg.a, key, absolute_key=False) == expected
 
     @mark.parametrize(
         ("key", "expected"),
@@ -300,4 +301,4 @@ def test_select_from_nested_node_absolute_key_interpretation(
         self, key: str, expected: Any
     ) -> None:
         cfg = OmegaConf.create(inp)
-        assert OmegaConf.select(cfg.a, key, absolute_key=True) == expected
+        assert select_value(cfg.a, key, absolute_key=True) == expected