[Python][UHI] Extend TH1 equality operator to consider additional properties

bindings/pyroot/pythonizations/python/ROOT/_pythonization/_uhi.py

@@ -386,6 +386,9 @@ def _eq(self, other):
         isinstance(other, type(self))
         and _shape(self) == _shape(other)
         and np.array_equal(_values_default(self), _values_default(other))
+        and self.kind == other.kind
+        and np.array_equal(_get_sum_of_weights_squared(self), _get_sum_of_weights_squared(other))
+        and all(a == b for a, b in zip(self.axes, other.axes))
     )
 
 
@@ -559,11 +562,12 @@ def _get_sum_of_weights_squared(self) -> np.typing.NDArray[Any]:  # noqa: F821
     import numpy as np
 
     shape = _shape(self, include_flow_bins=False)
-    return np.frombuffer(
+    sumw2_arr = np.frombuffer(
         self.GetSumw2().GetArray(),
         dtype=self.GetSumw2().GetArray().typecode,
         count=self.GetSumw2().GetSize(),
-    ).reshape(shape, order="F")[tuple([slice(1, -1)] * len(shape))]
+    )
+    return sumw2_arr[tuple([slice(1, -1)] * len(shape))].reshape(shape, order="F") if sumw2_arr.size > 0 else sumw2_arr
 
 
 values_func_dict: dict[str, Callable] = {

bindings/pyroot/pythonizations/test/uhi_indexing.py

@@ -315,6 +315,36 @@ def test_statistics_slice(self, hist_setup):
         assert hist_setup.GetStdDev() == pytest.approx(sliced_hist.GetStdDev(), rel=10e-5)
         assert hist_setup.GetMean() == pytest.approx(sliced_hist.GetMean(), rel=10e-5)
 
+    def test_equality_operator(self, hist_setup):
+        if _special_setting(hist_setup) or isinstance(hist_setup, (ROOT.TH1C, ROOT.TH2C, ROOT.TH3C)):
+            pytest.skip("This feature cannot be tested here")
+
+        assert hist_setup == hist_setup[...]
+
+        cloned_histograms = {
+            "content": hist_setup.Clone(),
+            "error": hist_setup.Clone(),
+            "weight": hist_setup.Clone(),
+            "axis": hist_setup.Clone(),
+        }
+        assert all(hist_setup == other for other in cloned_histograms.values())
+
+        # Change the content of a bin
+        cloned_histograms["content"].SetBinContent(1, 100)
+        assert hist_setup != cloned_histograms["content"]
+
+        # Change the error of a bin
+        cloned_histograms["error"].SetBinError(1, 10)
+        assert hist_setup != cloned_histograms["error"]
+
+        # Change the weight of a bin
+        cloned_histograms["weight"].AddBinContent(1, 100)
+        assert hist_setup != cloned_histograms["weight"]
+
+        # Change the x axis
+        cloned_histograms["axis"].GetXaxis().Set(10, 1, 5)
+        assert hist_setup != cloned_histograms["axis"]
+
 
 if __name__ == "__main__":
     pytest.main(args=[__file__])