Numpy 2.0 compatibility

Numpy 2.0 changes scalar repr as per:

     https://numpy.org/neps/nep-0051-scalar-representation.html

Make matplotlib_export convert to python scalars where appropriate
to avoid 'np.*' in generated code.

Author: ales-erjavec

orangewidget/tests/test_matplotlib_export.py

@@ -1,11 +1,15 @@
+import numpy as np
 import pyqtgraph as pg
 
 from orangewidget.tests.base import GuiTest
-from orangewidget.utils.matplotlib_export import scatterplot_code
+from orangewidget.utils.matplotlib_export import (
+    scatterplot_code, numpy_repr, compress_if_all_same, numpy_repr_int
+)
 
 
 def add_intro(a):
     r = "import matplotlib.pyplot as plt\n" + \
+        "import numpy as np\n" + \
         "from numpy import array\n" + \
         "plt.clf()"
     return r + a
@@ -15,8 +19,24 @@ class TestScatterPlot(GuiTest):
     def test_scatterplot_simple(self):
         plotWidget = pg.PlotWidget(background="w")
         scatterplot = pg.ScatterPlotItem()
-        scatterplot.setData(x=[1, 2, 3], y=[3, 2, 1])
+        scatterplot.setData(
+            x=np.array([1., 2, 3]),
+            y=np.array([3., 2, 1]),
+            size=np.array([1., 1, 1])
+        )
         plotWidget.addItem(scatterplot)
         code = scatterplot_code(scatterplot)
         self.assertIn("plt.scatter", code)
         exec(add_intro(code), {})
+
+    def test_utils(self):
+        a = np.array([1.5, 2.5])
+        self.assertIn("1.5, 2.5", numpy_repr(a))
+        a = np.array([1, 1])
+        v = compress_if_all_same(a)
+        self.assertEqual(v, 1)
+        self.assertEqual(repr(v), "1")
+        self.assertIs(type(v), int)
+        a = np.array([1, 2], dtype=int)
+        v = numpy_repr_int(a)
+        self.assertIn("1, 2", v)

orangewidget/utils/matplotlib_export.py

@@ -14,7 +14,7 @@ def numpy_repr(a):
     # avoid numpy repr as it changes between versions
     # TODO handle numpy repr differences
     if isinstance(a, np.ndarray):
-        return "array(" + repr(list(a)) + ")"
+        return "array(" + repr(a.tolist()) + ")"
     try:
         np.set_printoptions(threshold=10**10)
         return repr(a)
@@ -25,12 +25,16 @@ def numpy_repr(a):
 def numpy_repr_int(a):
     # avoid numpy repr as it changes between versions
     # TODO handle numpy repr differences
-    return "array(" + repr(list(a)) + ", dtype='int')"
+    return "array(" + repr(a.tolist()) + ", dtype='int')"
 
 
 def compress_if_all_same(l):
     s = set(l)
-    return s.pop() if len(s) == 1 else l
+    if len(s) == 1:
+        v = s.pop()
+        return v.item() if isinstance(v, np.generic) else v
+    else:
+        return l
 
 
 def is_sequence_not_string(a):