From bfd8df75615a42c32dcfb7e4f57acef92f6c6981 Mon Sep 17 00:00:00 2001
From: Isaac Virshup <ivirshup@gmail.com>
Date: Tue, 10 Oct 2023 23:35:12 +0200
Subject: [PATCH] simplify

---
 anndata/_core/merge.py                        | 22 +++++++++----------
 anndata/compat/__init__.py                    |  9 ++++++++
 anndata/experimental/merge.py                 | 15 ++++---------
 .../multi_files/_anncollection.py             | 14 ++++--------
 4 files changed, 28 insertions(+), 32 deletions(-)

diff --git a/anndata/_core/merge.py b/anndata/_core/merge.py
index e29bd759b..2df90e290 100644
--- a/anndata/_core/merge.py
+++ b/anndata/_core/merge.py
@@ -22,13 +22,19 @@
 import numpy as np
 import pandas as pd
 from natsort import natsorted
-from packaging.version import parse as parse_version
 from scipy import sparse
 from scipy.sparse import spmatrix
 
 from anndata._warnings import ExperimentalFeatureWarning
 
-from ..compat import AwkArray, CupyArray, CupyCSRMatrix, CupySparseMatrix, DaskArray
+from ..compat import (
+    AwkArray,
+    CupyArray,
+    CupyCSRMatrix,
+    CupySparseMatrix,
+    DaskArray,
+    _map_cat_to_str,
+)
 from ..utils import asarray, dim_len
 from .anndata import AnnData
 from .index import _subset, make_slice
@@ -1240,15 +1246,9 @@ def concat(
         [pd.Series(dim_indices(a, axis=axis)) for a in adatas], ignore_index=True
     )
     if index_unique is not None:
-        if parse_version(pd.__version__) >= parse_version("2.0"):
-            # Argument added in pandas 2.0
-            concat_indices = concat_indices.str.cat(
-                label_col.map(str, na_action="ignore"), sep=index_unique
-            )
-        else:
-            concat_indices = concat_indices.str.cat(
-                label_col.map(str), sep=index_unique
-            )
+        concat_indices = concat_indices.str.cat(
+            _map_cat_to_str(label_col), sep=index_unique
+        )
     concat_indices = pd.Index(concat_indices)
 
     alt_indices = merge_indices(
diff --git a/anndata/compat/__init__.py b/anndata/compat/__init__.py
index d6ab5c2f3..10a41d037 100644
--- a/anndata/compat/__init__.py
+++ b/anndata/compat/__init__.py
@@ -14,6 +14,7 @@
 import h5py
 import numpy as np
 import pandas as pd
+from packaging.version import parse as _parse_version
 from scipy.sparse import issparse, spmatrix
 
 from .exceptiongroups import add_note  # noqa: F401
@@ -391,3 +392,11 @@ def _safe_transpose(x):
         return _transpose_by_block(x)
     else:
         return x.T
+
+
+def _map_cat_to_str(cat: pd.Categorical):
+    if _parse_version(pd.__version__) >= _parse_version("2.0"):
+        # Argument added in pandas 2.0
+        return cat.map(str, na_action="ignore")
+    else:
+        return cat.map(str)
diff --git a/anndata/experimental/merge.py b/anndata/experimental/merge.py
index fef14a2ea..59c0623a8 100644
--- a/anndata/experimental/merge.py
+++ b/anndata/experimental/merge.py
@@ -13,7 +13,6 @@
 
 import numpy as np
 import pandas as pd
-from packaging.version import parse as parse_version
 from scipy.sparse import csc_matrix, csr_matrix
 
 from .._core.file_backing import to_memory
@@ -33,7 +32,7 @@
 )
 from .._core.sparse_dataset import BaseCompressedSparseDataset, sparse_dataset
 from .._io.specs import read_elem, write_elem
-from ..compat import H5Array, H5Group, ZarrArray, ZarrGroup
+from ..compat import H5Array, H5Group, ZarrArray, ZarrGroup, _map_cat_to_str
 from . import read_dispatched
 
 SPARSE_MATRIX = {"csc_matrix", "csr_matrix"}
@@ -597,15 +596,9 @@ def concat_on_disk(
         [pd.Series(_df_index(g[dim])) for g in groups], ignore_index=True
     )
     if index_unique is not None:
-        if parse_version(pd.__version__) >= parse_version("2.0"):
-            # Argument added in pandas 2.0
-            concat_indices = concat_indices.str.cat(
-                label_col.map(str, na_action="ignore"), sep=index_unique
-            )
-        else:
-            concat_indices = concat_indices.str.cat(
-                label_col.map(str), sep=index_unique
-            )
+        concat_indices = concat_indices.str.cat(
+            _map_cat_to_str(label_col), sep=index_unique
+        )
 
     # Resulting indices for {dim} and {alt_dim}
     concat_indices = pd.Index(concat_indices)
diff --git a/anndata/experimental/multi_files/_anncollection.py b/anndata/experimental/multi_files/_anncollection.py
index b5fa42a7d..acacdc8d3 100644
--- a/anndata/experimental/multi_files/_anncollection.py
+++ b/anndata/experimental/multi_files/_anncollection.py
@@ -8,7 +8,6 @@
 import numpy as np
 import pandas as pd
 from h5py import Dataset
-from packaging.version import parse as parse_version
 
 from ..._core.aligned_mapping import AxisArrays
 from ..._core.anndata import AnnData
@@ -16,6 +15,7 @@
 from ..._core.merge import concat_arrays, inner_concat_aligned_mapping
 from ..._core.sparse_dataset import BaseCompressedSparseDataset
 from ..._core.views import _resolve_idx
+from ...compat import _map_cat_to_str
 
 ATTRS = ["obs", "obsm", "layers"]
 
@@ -721,15 +721,9 @@ def __init__(
             categories=keys,
         )
         if index_unique is not None:
-            if parse_version(pd.__version__) >= parse_version("2.0"):
-                # Argument added in pandas 2.0
-                concat_indices = concat_indices.str.cat(
-                    label_col.map(str, na_action="ignore"), sep=index_unique
-                )
-            else:
-                concat_indices = concat_indices.str.cat(
-                    label_col.map(str), sep=index_unique
-                )
+            concat_indices = concat_indices.str.cat(
+                _map_cat_to_str(label_col), sep=index_unique
+            )
         self.obs_names = pd.Index(concat_indices)
 
         if not self.obs_names.is_unique: