From 760a322329f30f975d705faa0b85688d9e61cf65 Mon Sep 17 00:00:00 2001
From: colganwi <colgan.william@gmail.com>
Date: Mon, 2 Dec 2024 14:24:33 -0500
Subject: [PATCH] h5ad without X

---
 CHANGELOG.md               | 10 ++++++++++
 pyproject.toml             |  2 +-
 src/treedata/_core/read.py |  3 ++-
 tests/test_readwrite.py    |  8 ++++++++
 4 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2847c25..07d53ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,16 @@ and this project adheres to [Semantic Versioning][].
 
 ### Fixed
 
+## [0.1.2] - 2024-12-02
+
+### Added
+
+### Changed
+
+### Fixed
+
+-   Fixed `KeyError: "Unable to synchronously open object (object 'X' doesn't exist)"'` when reading h5ad without X field (#40)
+
 ## [0.1.1] - 2024-11-25
 
 ### Added
diff --git a/pyproject.toml b/pyproject.toml
index bd19974..da585fe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ requires = ["hatchling"]
 
 [project]
 name = "treedata"
-version = "0.1.1"
+version = "0.1.2"
 description = "anndata with trees"
 readme = "README.md"
 requires-python = ">=3.10"
diff --git a/src/treedata/_core/read.py b/src/treedata/_core/read.py
index 3bd9466..13ef36a 100755
--- a/src/treedata/_core/read.py
+++ b/src/treedata/_core/read.py
@@ -76,7 +76,8 @@ def _read_tdata(f, filename, backed) -> dict:
         backed = "r"
     # Read X if not backed
     if not backed:
-        d["X"] = _read_elem(f["X"])
+        if "X" in f:
+            d["X"] = _read_elem(f["X"])
     else:
         d.update({"filename": filename, "filemode": backed})
     # Read standard elements
diff --git a/tests/test_readwrite.py b/tests/test_readwrite.py
index 1b5bf2c..3ce3c1c 100755
--- a/tests/test_readwrite.py
+++ b/tests/test_readwrite.py
@@ -102,6 +102,14 @@ def test_read_anndata(X, tmp_path):
     assert tdata.obst_keys() == []
 
 
+def test_read_no_X(X, tmp_path):
+    tdata = td.TreeData(obs=pd.DataFrame(index=["0", "1", "2"]))
+    file_path = tmp_path / "test.h5ad"
+    tdata.write_h5ad(file_path)
+    tdata2 = td.read_h5ad(file_path)
+    assert tdata2.X is None
+
+
 def test_h5ad_backing(tdata, tree, tmp_path):
     tdata_copy = tdata.copy()
     assert not tdata.isbacked