PyO3: Better shape handling (#1143)

* Negative and `*args` shape handling

* Rename to `PyShapeWithHole` + validate that only one hole exists

* Regenerate stubs

---------

Co-authored-by: Laurent Mazare <laurent.mazare@gmail.com>

candle-pyo3/tests/native/test_shape.py

@@ -0,0 +1,31 @@
+from candle import Tensor
+from candle import rand
+import pytest
+
+
+def test_absolute_shapes_are_valid():
+    a = rand((10, 20))
+    assert a.shape == (10, 20)
+
+    b = rand(10, 20)
+    assert b.shape == (10, 20)
+    pytest.raises(OverflowError, lambda: rand((10, 20, -1)))
+    pytest.raises(OverflowError, lambda: rand(-1, 20))
+    pytest.raises(TypeError, lambda: rand("foo", True))
+
+
+def test_relative_shapes_are_valid():
+    a = rand(10, 20)
+    a = a.reshape((1, -1))
+    assert a.shape == (1, 200)
+
+    b = rand(10, 20)
+    b = b.reshape(-1, 1)
+    assert b.shape == (200, 1)
+
+    c = rand(10, 20)
+    pytest.raises(TypeError, lambda: c.reshape(1, "foo"))
+    pytest.raises(ValueError, lambda: c.reshape(1, -2))
+    pytest.raises(ValueError, lambda: c.reshape((-2, 1)))
+    pytest.raises(ValueError, lambda: c.reshape((0, 1)))
+    pytest.raises(ValueError, lambda: c.reshape((1, -1, -1)))