pytester: Hookrecorder: improve assertoutcome

changelog/6176.improvement.rst

@@ -0,0 +1 @@
+Improved failure reporting with pytester's ``Hookrecorder.assertoutcome``.

src/_pytest/pytester.py

@@ -332,10 +332,17 @@ def countoutcomes(self) -> List[int]:
  return [len(x) for x in self.listoutcomes()]
 
  def assertoutcome(self, passed: int = 0, skipped: int = 0, failed: int = 0) -> None:
- realpassed, realskipped, realfailed = self.listoutcomes()
- assert passed == len(realpassed)
- assert skipped == len(realskipped)
- assert failed == len(realfailed)
+ __tracebackhide__ = True
+
+ outcomes = self.listoutcomes()
+ realpassed, realskipped, realfailed = outcomes
+ obtained = {
+ "passed": len(realpassed),
+ "skipped": len(realskipped),
+ "failed": len(realfailed),
+ }
+ expected = {"passed": passed, "skipped": skipped, "failed": failed}
+ assert obtained == expected, outcomes
 
  def clear(self) -> None:
  self.calls[:] = []

testing/test_assertion.py

@@ -70,7 +70,14 @@ def test_dummy_failure(testdir): # how meta!
  """
  )
  result = testdir.runpytest_subprocess()
- result.stdout.fnmatch_lines(["*assert 1 == 0*"])
+ result.stdout.fnmatch_lines(
+ [
+ "E * AssertionError: ([[][]], [[][]], [[]<TestReport *>[]])*",
+ "E * assert"
+ " {'failed': 1, 'passed': 0, 'skipped': 0} =="
+ " {'failed': 0, 'passed': 1, 'skipped': 0}",
+ ]
+ )
 
  @pytest.mark.parametrize("mode", ["plain", "rewrite"])
  def test_pytest_plugins_rewrite(self, testdir, mode):