itertools: fix count() repr to show float step 1.0 (#8261)

Assisted-by: Claude Code:claude-opus-4-8

Lib/test/test_itertools.py

@@ -538,7 +538,6 @@ class TestBasicOps(unittest.TestCase):
         #check proper internal error handling for large "step' sizes
         count(1, maxsize+5); sys.exc_info()
 
-    @unittest.expectedFailure  # TODO: RUSTPYTHON; 'count(10.5)' != 'count(10.5, 1.0)'
     def test_count_with_step(self):
         self.assertEqual(lzip('abc',count(2,3)), [('a', 2), ('b', 5), ('c', 8)])
         self.assertEqual(lzip('abc',count(start=2,step=3)),

crates/vm/src/stdlib/itertools.rs

@@ -225,7 +225,9 @@ mod decl {
             let step = &zelf.step;
             let mut result = Wtf8Buf::from("count(");
             result.push_wtf8(cur_repr.as_wtf8());
-            if !vm.bool_eq(step, vm.ctx.new_int(1).as_object())? {
+            let step_is_int_one = step.fast_isinstance(vm.ctx.types.int_type)
+                && vm.bool_eq(step, vm.ctx.new_int(1).as_object())?;
+            if !step_is_int_one {
                 result.push_str(", ");
                 result.push_wtf8(step.repr(vm)?.as_wtf8());
             }