Conditionally include failing examples rather than handle them in the testing code

test/failing_examples.py

@@ -29,7 +29,6 @@ FAILING_EXAMPLES = [
     'from foo import a,',
     'from __future__ import whatever',
     'from __future__ import braces',
-    'from .__future__ import whatever',
     'def f(x=3, y): pass',
     'lambda x=3, y: x',
     '__debug__ = 1',
@@ -216,7 +215,6 @@ FAILING_EXAMPLES = [
     'f"{\'\\\'}"',
     'f"{#}"',
     "f'{1!b}'",
-    "f'{1:{5:{3}}}'",
     "f'{'",
     "f'{'",
     "f'}'",
@@ -411,3 +409,17 @@ if sys.version_info[:2] >= (3, 8):
     FAILING_EXAMPLES += [
         "f'{1=!b}'",
     ]
+
+if sys.version_info[:2] < (3, 12):
+    FAILING_EXAMPLES += [
+        # f-string expression part cannot include a backslash before 3.12
+        r'''f"{'\n'}"''',
+        # this compiles successfully but fails when evaluated in 3.12
+        "f'{1:{5:{3}}}'",
+    ]
+
+if sys.version_info[:2] < (3, 13):
+    # this compiles successfully but fails when evaluated in 3.13
+    FAILING_EXAMPLES += [
+        'from .__future__ import whatever',
+    ]

test/test_python_errors.py

@@ -105,7 +105,7 @@ def _get_actual_exception(code):
         # It's as simple as either an error or not.
         warnings.filterwarnings('ignore', category=SyntaxWarning)
         try:
-            compiled = compile(code, '<unknown>', 'exec')
+            compile(code, '<unknown>', 'exec')
         except (SyntaxError, IndentationError) as e:
             wanted = e.__class__.__name__ + ': ' + e.msg
             line_nr = e.lineno
@@ -115,20 +115,7 @@ def _get_actual_exception(code):
             wanted = 'SyntaxError: (value error) ' + str(e)
             line_nr = None
         else:
-            # In Python 3.12+, some invalid f-strings compile OK but
-            # only raise an exception when they are evaluated.
-            try:
-                eval(compiled)
-            except ValueError as e:
-                wanted = 'SyntaxError: (value error) ' + str(e)
-                line_nr = None
-            except (ImportError, ModuleNotFoundError):
-                # This comes from 'from .__future__ import whatever'
-                # in Python 3.13+
-                wanted = 'SyntaxError: future feature whatever is not defined'
-                line_nr = None
-            else:
-                assert False, "The piece of code should raise an exception."
+            assert False, "The piece of code should raise an exception."
 
     # SyntaxError
     # Some errors have changed error message in later versions of Python,