fix(format): a dataset attribute set again replaces the earlier value

b0a1e4f fixed this for group and root attributes only. Setting a dataset attribute twice still wrote two attribute messages with one name, and h5py read back the first value: set_attr("a", 1) then set_attr("a", 2) read as 1, and list(attrs) was ["a", "a"]. DatasetBuilder::set_attr now replaces the earlier value, compact or dense. Likewise, a hand-set attribute named like a provenance attribute (_provenance_sha256, ...) is replaced by the computed one instead of being written next to it and read first. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>
2026-09-26 09:02:09 -05:00
parent 400e3a9fec
commit 8bcae3c78e
3 changed files with 72 additions and 2 deletions
@@ -876,3 +876,65 @@ fn chained_hard_links_resolve_in_linear_time() {
        assert_eq!(f.dataset("g/s59/s0/v").unwrap().read_i32().unwrap(), [5]);
    }
 }
+
+#[test]
+fn a_dataset_attribute_set_again_takes_the_new_value() {
+    skip_if_no_python!();
+    // Setting a dataset attribute twice wrote two attribute messages with
+    // one name, and h5py read back the first value. Also with dense
+    // attribute storage (more than 8).
+    let dir = tempfile::tempdir().unwrap();
+    let mut b = FileBuilder::new();
+    b.create_dataset("x")
+        .with_f64_data(&[1.0])
+        .set_attr("a", AttrValue::I64(1))
+        .set_attr("a", AttrValue::I64(2));
+    let d = b.create_dataset("dense");
+    d.with_i32_data(&[1]);
+    for i in 0..12 {
+        d.set_attr(&format!("k{i:02}"), AttrValue::I64(i));
+    }
+    d.set_attr("k03", AttrValue::String("three".into()));
+    let path = write(&dir, "ds_attrs.h5", b);
+    let out = h5py(
+        &path,
+        "with h5py.File(path, 'r') as f:\n\
+         \x20   a, d = f['x'].attrs, f['dense'].attrs\n\
+         \x20   print(json.dumps([list(a), int(a['a']), len(d), d['k03'].decode(), int(d['k04'])]))",
+    );
+    assert_eq!(out, r#"[["a"], 2, 12, "three", 4]"#);
+    let f = File::open(&path).unwrap();
+    assert!(matches!(
+        f.dataset("x").unwrap().attrs().unwrap()["a"],
+        AttrValue::I64(2)
+    ));
+}
+
+#[cfg(feature = "provenance")]
+#[test]
+fn provenance_attributes_replace_ones_set_by_hand() {
+    skip_if_no_python!();
+    // A hand-set attribute with a provenance attribute's name was written
+    // next to the computed one, and h5py read the hand-set value.
+    let dir = tempfile::tempdir().unwrap();
+    let mut b = FileBuilder::new();
+    b.create_dataset("p")
+        .with_i32_data(&[1, 2])
+        .with_provenance("me", "2026-09-26T00:00:00Z", None)
+        .set_attr("_provenance_sha256", AttrValue::String("forged".into()));
+    let path = write(&dir, "prov.h5", b);
+    let out = h5py(
+        &path,
+        "with h5py.File(path, 'r') as f:\n\
+         \x20   a = f['p'].attrs\n\
+         \x20   h = a['_provenance_sha256']\n\
+         \x20   h = h.decode() if isinstance(h, bytes) else h\n\
+         \x20   print(json.dumps([list(a).count('_provenance_sha256'), h != 'forged']))",
+    );
+    assert_eq!(out, "[1, true]");
+    let f = File::open(&path).unwrap();
+    assert_eq!(
+        f.dataset("p").unwrap().verify_provenance().unwrap(),
+        clawhdf5_format::provenance::VerifyResult::Ok
+    );
+}