fix: AxesTuple constuctor more strict

Author: henryiii

docs/CHANGELOG.md

@@ -2,6 +2,18 @@
 
 ## Version 1.2
 
+### Version 1.2.2
+
+#### User changes
+
+* PyPy 3.8 now supported. [#677][]
+* The GIL is released a little more often now. [#662][]
+* AxesTuple does not allow construction of non-axes. [#680][]
+
+[#662]: https://github.com/scikit-hep/boost-histogram/pull/662
+[#677]: https://github.com/scikit-hep/boost-histogram/pull/677
+[#680]: https://github.com/scikit-hep/boost-histogram/pull/680
+
 ### Version 1.2.1
 
 #### User changes

src/boost_histogram/_internal/axestuple.py

@@ -1,5 +1,5 @@
 from functools import partial
-from typing import Any, List, Tuple, TypeVar
+from typing import Any, Iterable, List, Tuple, Type, TypeVar
 
 import numpy as np
 
@@ -45,6 +45,15 @@ class AxesTuple(tuple):  # type: ignore[type-arg]
     __slots__ = ()
     _MGRIDOPTS = {"sparse": True, "indexing": "ij"}
 
+    def __new__(cls: Type[B], __iterable: Iterable[Axis]) -> B:
+        self = super().__new__(cls, __iterable)  # type: ignore[arg-type]
+        for item in self:
+            if not isinstance(item, Axis):
+                raise TypeError(
+                    f"Only an iterable of Axis supported in AxesTuple, got {item}"
+                )
+        return self
+
     @property
     def size(self) -> Tuple[int, ...]:
         return tuple(s.size for s in self)
@@ -93,14 +102,15 @@ def __getitem__(self, item: Any) -> Any:
         result = super().__getitem__(item)
         return self.__class__(result) if isinstance(result, tuple) else result
 
-    def __getattr__(self, attr: str) -> Any:
-        return self.__class__(getattr(s, attr) for s in self)
+    def __getattr__(self, attr: str) -> Tuple[Any, ...]:
+        return tuple(getattr(s, attr) for s in self)
 
     def __setattr__(self, attr: str, values: Any) -> None:
         try:
             return super().__setattr__(attr, values)
         except AttributeError:
-            self.__class__(s.__setattr__(attr, v) for s, v in zip_strict(self, values))
+            for s, v in zip_strict(self, values):
+                s.__setattr__(attr, v)
 
     value.__doc__ = Axis.value.__doc__
     index.__doc__ = Axis.index.__doc__

tests/test_axes_object.py

@@ -1,9 +1,19 @@
 import numpy as np
+import pytest
 
 import boost_histogram as bh
 
 
-def test_axes_all_at_once():
+@pytest.fixture
+def h():
+    return bh.Histogram(
+        bh.axis.Regular(10, 0, 10, metadata=2),
+        bh.axis.Integer(0, 5, metadata="hi"),
+        bh.axis.StrCategory(["HI", "HO"]),
+    )
+
+
+def test_axes_basics(h):
     h = bh.Histogram(
         bh.axis.Regular(10, 0, 10, metadata=2),
         bh.axis.Integer(0, 5, metadata="hi"),
@@ -22,6 +32,8 @@ def test_axes_all_at_once():
 
     assert h.axes.metadata == (None, 3, "bye")
 
+
+def test_axes_centers(h):
     centers = h.axes.centers
     answers = np.ogrid[0.5:10, 0.5:5, 0.5:2]
     full_answers = np.mgrid[0.5:10, 0.5:5, 0.5:2]
@@ -33,6 +45,8 @@ def test_axes_all_at_once():
         np.testing.assert_allclose(centers.flatten()[i], answers[i].flatten())
         np.testing.assert_allclose(h.axes[i].centers, answers[i].ravel())
 
+
+def test_axes_edges(h):
     edges = h.axes.edges
     answers = np.ogrid[0:11, 0:6, 0:3]
     full_answers = np.mgrid[0:11, 0:6, 0:3]
@@ -44,6 +58,8 @@ def test_axes_all_at_once():
         np.testing.assert_allclose(edges.ravel()[i], answers[i].ravel())
         np.testing.assert_allclose(h.axes[i].edges, answers[i].ravel())
 
+
+def test_axes_widths(h):
     widths = h.axes.widths
     answers = np.ogrid[1:1:10j, 1:1:5j, 1:1:2j]
     full_answers = np.mgrid[1:1:10j, 1:1:5j, 1:1:2j]
@@ -54,3 +70,12 @@ def test_axes_all_at_once():
         np.testing.assert_allclose(widths.T[i], answers[i].T)
         np.testing.assert_allclose(widths.ravel()[i], answers[i].ravel())
         np.testing.assert_allclose(h.axes[i].widths, answers[i].ravel())
+
+
+def test_axis_misconstuct():
+    inp = [bh.axis.Regular(12, 0, 1)]
+    ok = bh.axis.AxesTuple(inp)
+    assert ok[0] == inp[0]
+
+    with pytest.raises(TypeError):
+        bh.axis.AxesTuple(inp[0])