From b56a638c010f42529b4c69a663c5c297e3c819c8 Mon Sep 17 00:00:00 2001
From: Natanael Copa <ncopa@alpinelinux.org>
Date: Mon, 13 May 2024 08:43:49 +0200
Subject: [PATCH] Treat methodName="runTest" similar to unittest.TestCase

pytest 8.2 relies on a feature of `unittest.TestCase` where the
initialization of it with the default `methodName="runTest"` is treated
specially, allowing it to insantiate even without `runTest` method
actually existing.

See under "Changed in Python 3.2" in unittest.TestCase docs

This fixes the error with pytest 8.2:
  AttributeError: 'TestUtil' object has no attribute 'runTest'. Did you mean: 'subTest'?

Fixes: https://github.com/testing-cabal/testtools/issues/372
ref: https://docs.python.org/3/library/unittest.html#unittest.TestCase
ref: https://github.com/python/cpython/blob/51aefc5bf907ddffaaf083ded0de773adcdf08c8/Lib/unittest/case.py#L419-L426
ref: https://github.com/pytest-dev/pytest/issues/12263#issuecomment-2081434468
---
 testtools/testcase.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/testtools/testcase.py b/testtools/testcase.py
index 08b158b6..fefa3e7e 100644
--- a/testtools/testcase.py
+++ b/testtools/testcase.py
@@ -735,7 +735,17 @@ def _run_teardown(self, result):
 
     def _get_test_method(self):
         method_name = getattr(self, "_testMethodName")
-        return getattr(self, method_name)
+        try:
+            m = getattr(self, method_name)
+        except AttributeError:
+            if method_name != "runTest":
+                # We allow instantiation with no explicit method name
+                # but not an *incorrect* or missing method name.
+                raise ValueError(
+                        "no such test method in %s: %s" % (self.__class__, method_name)
+                )
+        else:
+            return m
 
     def _run_test_method(self, result):
         """Run the test method for this test.