diff --git a/Lib/test/test_venv.py b/Lib/test/test_venv.py index 94d626598bac38..eca35ec4bfd1ab 100644 --- a/Lib/test/test_venv.py +++ b/Lib/test/test_venv.py @@ -5,6 +5,7 @@ Licensed to the PSF under a contributor agreement. """ +import contextlib import ensurepip import os import os.path @@ -478,16 +479,10 @@ def do_test_with_pip(self, system_site_packages): # Actually run the create command with all that unhelpful # config in place to ensure we ignore it - try: + with self.nicer_error(): self.run_with_capture(venv.create, self.env_dir, system_site_packages=system_site_packages, with_pip=True) - except subprocess.CalledProcessError as exc: - # The output this produces can be a little hard to read, - # but at least it has all the details - details = exc.output.decode(errors="replace") - msg = "{}\n\n**Subprocess Output**\n{}" - self.fail(msg.format(exc, details)) # Ensure pip is available in the virtual environment envpy = os.path.join(os.path.realpath(self.env_dir), self.bindir, self.exe) # Ignore DeprecationWarning since pip code is not part of Python @@ -508,13 +503,14 @@ def do_test_with_pip(self, system_site_packages): # Check the private uninstall command provided for the Windows # installers works (at least in a virtual environment) with EnvironmentVarGuard() as envvars: - # It seems ensurepip._uninstall calls subprocesses which do not - # inherit the interpreter settings. - envvars["PYTHONWARNINGS"] = "ignore" - out, err = check_output([envpy, - '-W', 'ignore::DeprecationWarning', - '-W', 'ignore::ImportWarning', '-I', - '-m', 'ensurepip._uninstall']) + with self.nicer_error(): + # It seems ensurepip._uninstall calls subprocesses which do not + # inherit the interpreter settings. + envvars["PYTHONWARNINGS"] = "ignore" + out, err = check_output([envpy, + '-W', 'ignore::DeprecationWarning', + '-W', 'ignore::ImportWarning', '-I', + '-m', 'ensurepip._uninstall']) # We force everything to text, so unittest gives the detailed diff # if we get unexpected results err = err.decode("latin-1") # Force to text, prevent decoding errors @@ -540,6 +536,25 @@ def do_test_with_pip(self, system_site_packages): if not system_site_packages: self.assert_pip_not_installed() + @contextlib.contextmanager + def nicer_error(self): + """ + Capture output from a failed subprocess for easier debugging. + + The output this handler produces can be a little hard to read, + but at least it has all the details. + """ + try: + yield + except subprocess.CalledProcessError as exc: + out = exc.output.decode(errors="replace") + err = exc.stderr.decode(errors="replace") + self.fail( + f"{exc}\n\n" + f"**Subprocess Output**\n{out}\n\n" + f"**Subprocess Error**\n{err}" + ) + # Issue #26610: pip/pep425tags.py requires ctypes @unittest.skipUnless(ctypes, 'pip requires ctypes') @requires_zlib() @@ -547,5 +562,6 @@ def test_with_pip(self): self.do_test_with_pip(False) self.do_test_with_pip(True) + if __name__ == "__main__": unittest.main() diff --git a/Misc/NEWS.d/next/Tests/2022-06-17-13-55-11.gh-issue-93957.X4ovYV.rst b/Misc/NEWS.d/next/Tests/2022-06-17-13-55-11.gh-issue-93957.X4ovYV.rst new file mode 100644 index 00000000000000..2719933f6b94c7 --- /dev/null +++ b/Misc/NEWS.d/next/Tests/2022-06-17-13-55-11.gh-issue-93957.X4ovYV.rst @@ -0,0 +1,2 @@ +Provide nicer error reporting from subprocesses in +test_venv.EnsurePipTest.test_with_pip.