Revert "[WIP] ExplicitlyIndexedBackendArray"

This reverts commit 9b727e6.

xarray/backends/cfgrib_.py

@@ -13,7 +13,6 @@
     AbstractDataStore,
     BackendArray,
     BackendEntrypoint,
-    ExplicitlyIndexedBackendArray,
     _normalize_path,
 )
 from .locks import SerializableLock, ensure_lock
@@ -33,8 +32,8 @@ def __init__(self, datastore, array):
         self.array = array
 
     def __getitem__(self, key):
-        return ExplicitlyIndexedBackendArray(
-            self, key, self.shape, indexing.IndexingSupport.BASIC, self._getitem
+        return indexing.explicit_indexing_adapter(
+            key, self.shape, indexing.IndexingSupport.BASIC, self._getitem
         )
 
     def _getitem(self, key):

xarray/backends/common.py

@@ -88,25 +88,6 @@ def get_duck_array(self, dtype=None):
         return self[key]
 
 
-class ExplicitlyIndexedBackendArray(BackendArray):
-    def __init__(
-        self, backend_array, key, shape, indexing_support, raw_indexing_method
-    ):
-        self.backend_array = backend_array
-        self.key = key
-        self.shape = shape
-        self.indexing_support = indexing_support
-        self.raw_indexing_method = raw_indexing_method
-
-    def get_duck_array(self):
-        return indexing.explicit_indexing_adapter(
-            self.key, self.shape, self.indexing_support, self.raw_indexing_method
-        )
-
-    def repr(self):
-        return f"ExplicitlyIndexedBackendArray({type(self.backend_array)})"
-
-
 class AbstractDataStore:
     __slots__ = ()
 

xarray/backends/h5netcdf_.py

@@ -19,7 +19,6 @@
 from .common import (
     BACKEND_ENTRYPOINTS,
     BackendEntrypoint,
-    ExplicitlyIndexedBackendArray,
     WritableCFDataStore,
     _normalize_path,
     find_root_and_group,
@@ -42,8 +41,8 @@ def get_array(self, needs_lock=True):
         return ds.variables[self.variable_name]
 
     def __getitem__(self, key):
-        return ExplicitlyIndexedBackendArray(
-            self, key, self.shape, indexing.IndexingSupport.OUTER_1VECTOR, self._getitem
+        return indexing.explicit_indexing_adapter(
+            key, self.shape, indexing.IndexingSupport.OUTER_1VECTOR, self._getitem
         )
 
     def _getitem(self, key):

xarray/backends/netCDF4_.py

@@ -22,7 +22,6 @@
     BACKEND_ENTRYPOINTS,
     BackendArray,
     BackendEntrypoint,
-    ExplicitlyIndexedBackendArray,
     WritableCFDataStore,
     _normalize_path,
     find_root_and_group,
@@ -83,8 +82,8 @@ def get_array(self, needs_lock=True):
         return variable
 
     def __getitem__(self, key):
-        return ExplicitlyIndexedBackendArray(
-            self, key, self.shape, indexing.IndexingSupport.OUTER, self._getitem
+        return indexing.explicit_indexing_adapter(
+            key, self.shape, indexing.IndexingSupport.OUTER, self._getitem
         )
 
     def _getitem(self, key):

xarray/coding/strings.py

@@ -236,6 +236,4 @@ def __getitem__(self, key):
         key = type(key)(indexing.expanded_indexer(key.tuple, self.array.ndim))
         if key.tuple[-1] != slice(None):
             raise IndexError("too many indices")
-
-        dtype = "S" + str(self.array.shape[-1])
-        return lazy_elemwise_func(self.array[key], _numpy_char_to_bytes, dtype)
+        return _numpy_char_to_bytes(self.array[key])

xarray/core/indexing.py

@@ -528,7 +528,12 @@ def shape(self) -> tuple[int, ...]:
     def get_duck_array(self):
         array = as_indexable(self.array)
         array = array[self.key]
-        array = array.get_duck_array()
+        # array[self.key] is now a numpy array when
+        # self.array is a BackendArray subclass
+        # and self.key is BasicIndexer((slice(None, None, None),))
+        # so we need the explicit check for ExplicitlyIndexed
+        if isinstance(array, ExplicitlyIndexed):
+            array = array.get_duck_array()
         return array
 
     def transpose(self, order):