Fix fixup code and add test

Author: erlend-aasland

Lib/test/test_clinic.py

@@ -1483,6 +1483,18 @@ def test_parameters_required_after_star(self):
             with self.subTest(block=block):
                 self.expect_failure(block, err)
 
+    def test_parameters_required_after_depr_star(self):
+        dataset = (
+            "module foo\nfoo.bar\n  * [from 3.14]",
+            "module foo\nfoo.bar\n  * [from 3.14]\nDocstring here.",
+            "module foo\nfoo.bar\n  this: int\n  * [from 3.14]",
+            "module foo\nfoo.bar\n  this: int\n  * [from 3.14]\nDocstring.",
+        )
+        err = "Function 'foo.bar' specifies '* [from 3.14]' without any parameters afterwards."
+        for block in dataset:
+            with self.subTest(block=block):
+                self.expect_failure(block, err)
+
     def test_depr_star_invalid_format_1(self):
         block = """
             module foo

Tools/clinic/clinic.py

@@ -5729,12 +5729,10 @@ def check_remaining(
         ) -> None:
             assert isinstance(self.function, Function)
 
-            if values := self.function.parameters.values():
-                last_param = next(reversed(values))
-                no_param_after_symbol = condition(last_param)
-            else:
-                no_param_after_symbol = True
-            if no_param_after_symbol:
+            values = self.function.parameters.values()
+            assert values
+            last_param = next(reversed(values))
+            if condition(last_param):
                 fname = self.function.full_name
                 fail(f"Function {fname!r} specifies {symbol!r} "
                      "without any parameters afterwards.", line_number=lineno)