ENH: capture and report build errors when rebuilding editable wheels

mesonpy/_editable.py

@@ -319,7 +319,7 @@ def _work_to_do(self, env: dict[str, str]) -> bool:
  dry_run_build_cmd = self._build_cmd + ['-n']
  # Check adapted from
  # https://github.com/mesonbuild/meson/blob/a35d4d368a21f4b70afa3195da4d6292a649cb4c/mesonbuild/mtest.py#L1635-L1636
- p = subprocess.run(dry_run_build_cmd, cwd=self._build_path, env=env, capture_output=True)
+ p = subprocess.run(dry_run_build_cmd, cwd=self._build_path, env=env, check=False, capture_output=True)
  return b'ninja: no work to do.' not in p.stdout and b'samu: nothing to do' not in p.stdout
 
  @functools.lru_cache(maxsize=1)
@@ -332,15 +332,43 @@ def _rebuild(self) -> Node:
  env[MARKER] = os.pathsep.join((env.get(MARKER, ''), self._build_path))
 
  if self._verbose or bool(env.get(VERBOSE, '')):
+ log_path = None
  # We want to show some output only if there is some work to do.
  if self._work_to_do(env):
  build_command = ' '.join(self._build_cmd)
  print(f'meson-python: building {self._name}: {build_command}', flush=True)
  subprocess.run(self._build_cmd, cwd=self._build_path, env=env, check=True)
  else:
- subprocess.run(self._build_cmd, cwd=self._build_path, env=env, stdout=subprocess.DEVNULL, check=True)
- except subprocess.CalledProcessError as exc:
- raise ImportError(f're-building the {self._name} meson-python editable wheel package failed') from exc
+ # Redirect build log to file.
+ log_path = os.path.join(self._build_path, 'meson-logs', 'meson-python-build-log.txt')
+ with open(log_path, 'w') as log:
+ subprocess.run(self._build_cmd, cwd=self._build_path, env=env, check=True,
+ stderr=subprocess.STDOUT, stdout=log)
+ except subprocess.CalledProcessError as err:
+ msg = f'rebuilding the "{self._name}" editable package failed'
+ if log_path:
+ with open(log_path, 'r', encoding='utf8') as log:
+ # Skip to the error.
+ for line in log:
+ if line.startswith('FAILED: '):
+ break
+ else:
+ # When no `FAILED: ` line is found, rewind to the
+ # beginning of the log.
+ log.seek(0)
+ if line.strip().endswith(' build.ninja'):
+ # When the error occurred when rebuilding `ninja.build`,
+ # the meson output appears before the `FAILED: ` line.
+ # Rewind the build log to the beginning to report the
+ # error.
+ log.seek(0)
+ error = log.read()
+ if sys.version_info >= (3, 11):
+ exc = ImportError(msg)
+ exc.add_note(error)
+ raise exc from err
+ msg = f'{msg}:\n{error}'
+ raise ImportError(msg) from err
 
  install_plan_path = os.path.join(self._build_path, 'meson-info', 'intro-install_plan.json')
  with open(install_plan_path, 'r', encoding='utf8') as f:

tests/test_editable.py

@@ -332,13 +332,53 @@ def test_editable_rebuild_error(package_purelib_and_platlib, tmp_path, verbose):
  # Insert invalid code in the extension module source code
  path.write_text('return')
 
- # Import module and trigger rebuild: the build fails and ImportErrror is raised
+ # Import module and trigger rebuild: the build fails and ImportError is raised
  stdout = io.StringIO()
  with redirect_stdout(stdout):
- with pytest.raises(ImportError, match='re-building the purelib-and-platlib '):
+ with pytest.raises(ImportError, match='rebuilding the "purelib-and-platlib" ') as exc:
  import plat # noqa: F401
  assert not verbose or stdout.getvalue().startswith('meson-python: building ')
 
+ if sys.version_info >= (3, 11):
+ assert verbose or hasattr(exc.value, '__notes__')
+ assert verbose or 'ninja: build stopped: subcommand failed.' in exc.value.__notes__[0]
+ else:
+ assert verbose or 'ninja: build stopped: subcommand failed.' in exc.value.msg
+
+ finally:
+ del sys.meta_path[0]
+ sys.modules.pop('pure', None)
+ path.write_text(code)
+
+
+def test_editable_reconfigure_error(package_purelib_and_platlib, tmp_path):
+ with mesonpy._project({'builddir': os.fspath(tmp_path)}) as project:
+
+ finder = _editable.MesonpyMetaFinder(
+ project._metadata.name, {'plat', 'pure'},
+ os.fspath(tmp_path), project._build_command,
+ verbose=False,
+ )
+ path = package_purelib_and_platlib / 'meson.build'
+ code = path.read_text()
+
+ try:
+ # Install editable hooks
+ sys.meta_path.insert(0, finder)
+
+ # Emit an error (with unicode characters) during reconfigure
+ with open(path, 'a', encoding='utf8') as f:
+ f.write('\n\nerror(\'injected error \N{BOMB}\')\n')
+
+ # Import module and trigger rebuild: the build fails and ImportErrror is raised
+ stdout = io.StringIO()
+ with redirect_stdout(stdout):
+ with pytest.raises(ImportError, match='rebuilding the "purelib-and-platlib" ') as exc:
+ import plat # noqa: F401
+ msg = exc.value.__notes__[0] if sys.version_info >= (3, 11) else exc.value.msg
+ assert 'ERROR: Problem encountered: injected error' in msg
+ assert 'ninja: error: rebuilding \'build.ninja\': subcommand failed' in msg
+
  finally:
  del sys.meta_path[0]
  sys.modules.pop('pure', None)