HDF5 2.0 native complex as a first-class type on read; Python libver=

- Datatype::parse returns Datatype::Complex for class 11 (also inside
  compounds, arrays and VL types) instead of the {r, i} compound view.
- Facade: DType::Complex(Box<DType>); read_complex_f32/f64 accept it.
- h5rs dump/ls/diff print native complex as h5dump/h5ls/h5diff 2.2.0 do
  (checked against a fixture written by h5py 3.16 / libhdf5 2.0.0);
  dump --json keeps the {r, i} compound (hdf5-json has no complex class).
- clawhdf5-wasm reads native complex datasets as [re, im] pairs.
- Python: clawhdf5.File(path, 'w', libver=...) with h5py's values,
  mapped to FileBuilder::libver_bounds; 'v108' output opens in HDF5 1.8.23.
- Docs: known-issues entry moved to Fixed (history), CHANGELOG, READMEs.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

examples/wasm-viewer/README.md

@@ -123,8 +123,12 @@ else throws an `Error` naming the type.
   `readHyperslab`). Files of 4 GiB or more are refused at open (wasm32).
   Every response body is cut off past the length asked for. More in
   `docs/known-issues.md`.
-- Compound, reference, opaque and variable-length-sequence datasets are
-  refused with an error. Attributes of those types are listed with
+- HDF5 2.0 native complex datasets read as `[re, im]` pairs: `dtype`
+  `complex<f64>`, `elementShape` ending in `2`, the parts interleaved in
+  the typed array.
+- Compound (h5py's complex numbers, a compound `{r, i}`, included),
+  reference, opaque and variable-length-sequence datasets are refused with
+  an error. Attributes of those types are listed with
   `value: null` and their `dtype`.
 - No Zstd or SZIP filters (they link C): such a dataset fails with
   `unsupported filter`. Deflate, shuffle, Fletcher-32, LZ4, N-Bit and

examples/wasm-viewer/test/browser.sh

@@ -93,6 +93,12 @@ expect $H5 "/vlen_str" '<td>"двa"</td>' '<dd>vlen string</dd>'
 expect $H5 "/pairs" '<td>[2, 3]</td>' '<dd>array[2]&lt;i32&gt;</dd>'
 # 3-D: leading dimension held at 0, window over the last two.
 expect $H5 "/cube" '<dd>(2, 5, 6)</dd>' '<td>29</td>' 'dim 0'
+# HDF5 2.0 native complex (written when h5py's libhdf5 is 2.0 or later):
+# each cell is the [re, im] pair.
+if "$PY" -c 'import sys, h5py; sys.exit(not getattr(h5py.get_config(), "has_native_complex", False))'; then
+    expect $H5 "/native_c128" '<dd>complex&lt;f64&gt;</dd>' '<dd>(3, 2)</dd>' '<td>[1, -1.5]</td>' \
+        '<td>[5, -7.5]</td>'
+fi
 # Unsupported type: an error, not values.
 expect $H5 "/table" 'class="error"' 'reading compound{x: f64, n: i32} datasets is not supported'
 # Cross-origin: the page is on 127.0.0.1, the file on localhost. CORS that

examples/wasm-viewer/test/make_fixture.py

@@ -80,6 +80,15 @@ with h5py.File(h5, "w") as f:
                          **hdf5plugin.Zstd())
     comp = np.zeros(2, dtype=[("x", "<f8"), ("n", "<i4")])
     f.create_dataset("table", data=comp)
+    if getattr(h5py.get_config(), "has_native_complex", False):
+        # HDF5 2.0 native complex (class 11): read as [re, im] pairs.
+        from h5py import h5d, h5s, h5t
+
+        for name, t, dt in [(b"native_c128", h5t.COMPLEX_IEEE_F64LE, "<c16"),
+                            (b"native_c64_be", h5t.COMPLEX_IEEE_F32BE, ">c8")]:
+            z = (np.arange(6) - 1.5j * np.arange(6)).reshape(3, 2).astype(dt)
+            d = h5d.create(f.id, name, t, h5s.create_simple(z.shape))
+            d.write(h5s.ALL, h5s.ALL, z, mtype=t)
     g = f.create_group("sensors")
     g.attrs["location"] = "lab"
     g.create_dataset("temp", data=np.array([21.5, 22.0, 22.25], dtype="<f4"))
@@ -105,6 +114,8 @@ def kind(dt):
         return "strings"
     if dt.subdtype is not None:
         return kind(dt.subdtype[0])
+    if dt.kind == "c":
+        return "f64" if dt.itemsize == 16 else "f32"
     if dt.kind == "f":
         return "f64" if dt.itemsize == 8 else "f32"
     if dt.kind in "iu":
@@ -120,20 +131,25 @@ def flat(a, k):
         return [x.decode() if isinstance(x, bytes) else str(x) for x in a.ravel()]
     if k.startswith(("i", "u")):
         return [str(int(x)) for x in a.ravel()]
+    if a.dtype.kind == "c":
+        # [re, im] pairs, in order.
+        a = np.stack([a.real, a.imag], axis=-1)
     return [float(x) for x in a.ravel()]
 
 
 def entry(ds, slab=None):
     k = kind(ds.dtype)
     data = ds[()]
-    e = {"kind": k, "shape": list(np.shape(data)), "values": flat(data, k)}
+    # A complex element reads as its two parts: one more dimension.
+    pair = [2] if ds.dtype.kind == "c" else []
+    e = {"kind": k, "shape": list(np.shape(data)) + pair, "values": flat(data, k)}
     if slab:
         start, count, stride = slab
         idx = tuple(slice(s, s + (c - 1) * st + 1, st)
                     for s, c, st in zip(start, count, stride))
         part = ds[idx]
         e["slab"] = {"start": start, "count": count, "stride": stride,
-                     "shape": list(part.shape), "values": flat(part, k)}
+                     "shape": list(part.shape) + pair, "values": flat(part, k)}
     return e
 
 
@@ -176,7 +192,10 @@ def describe(path):
                                           "datasets": sorted(sets)}
                 for n, o in members.items():
                     walk(key.rstrip("/") + "/" + n, o)
-            elif obj.dtype.names:
+            elif obj.dtype.names or (
+                    obj.dtype.kind == "c"
+                    and obj.id.get_type().get_class() != getattr(h5py.h5t, "COMPLEX", None)):
+                # h5py's own complex numbers are a compound {r, i}: refused.
                 expected["errors"][key] = "compound"
             else:
                 expected["datasets"][key] = entry(obj, slab_for(obj))

examples/wasm-viewer/test/test.mjs

@@ -399,7 +399,7 @@ async function remoteTests() {
   await fails(async () => {
     const f = await pkg.openUrl(`${base}/fix/fixture.h5`, {
       blockSize: 512,
-      fetch: tamper(async (r) => withHeaders(r, { "Content-Range": "bytes 0-511/25752" })),
+      fetch: tamper(async (r) => withHeaders(r, { "Content-Range": `bytes 0-511/${statSync(join(fixDir, "fixture.h5")).size}` })),
     });
     await f.read("/grid");
   }, /the server sent 0-511/, "wrong range");
@@ -550,7 +550,7 @@ async function floodTests() {
       const range = new Headers(init.headers).get("Range");
       if (range === "bytes=0-511") return fetch(url, init);
       const m = /^bytes=(\d+)-(\d+)$/.exec(range);
-      return new Response(f.body, { status: 206, headers: { "Content-Range": `bytes ${m[1]}-${m[2]}/25752` } });
+      return new Response(f.body, { status: 206, headers: { "Content-Range": `bytes ${m[1]}-${m[2]}/${statSync(join(fixDir, "fixture.h5")).size}` } });
     },
   }).catch((e) => e);
   // The open itself may need a second range: flooded either way.