report more details on build backend exception (#8464)

Co-authored-by: Randy Döring <[email protected]>

src/poetry/installation/chef.py

@@ -137,14 +137,12 @@ def _prepare(
                     )
             except BuildBackendException as e:
                 message_parts = [str(e)]
-                if isinstance(e.exception, CalledProcessError) and (
-                    e.exception.stdout is not None or e.exception.stderr is not None
-                ):
-                    message_parts.append(
-                        decode(e.exception.stderr)
-                        if e.exception.stderr is not None
-                        else decode(e.exception.stdout)
-                    )
+                if isinstance(e.exception, CalledProcessError):
+                    text = e.exception.stderr or e.exception.stdout
+                    if text is not None:
+                        message_parts.append(decode(text))
+                else:
+                    message_parts.append(str(e.exception))
 
                 error = ChefBuildError("\n\n".join(message_parts))
 

tests/installation/test_executor.py

@@ -1238,9 +1238,17 @@ def test_executor_fallback_on_poetry_create_error_without_wheel_installer(
 
 
 @pytest.mark.parametrize("failing_method", ["build", "get_requires_for_build"])
+@pytest.mark.parametrize(
+    "exception",
+    [
+        CalledProcessError(1, ["pip"], output=b"original error"),
+        Exception("original error"),
+    ],
+)
 @pytest.mark.parametrize("editable", [False, True])
 def test_build_backend_errors_are_reported_correctly_if_caused_by_subprocess(
     failing_method: str,
+    exception: Exception,
     editable: bool,
     mocker: MockerFixture,
     config: Config,
@@ -1250,9 +1258,7 @@ def test_build_backend_errors_are_reported_correctly_if_caused_by_subprocess(
     env: MockEnv,
     fixture_dir: FixtureDirGetter,
 ) -> None:
-    error = BuildBackendException(
-        CalledProcessError(1, ["pip"], output=b"Error on stdout")
-    )
+    error = BuildBackendException(exception, description="hide the original error")
     mocker.patch.object(ProjectBuilder, failing_method, side_effect=error)
     io.set_verbosity(Verbosity.NORMAL)
 
@@ -1282,10 +1288,10 @@ def test_build_backend_errors_are_reported_correctly_if_caused_by_subprocess(
 
   ChefBuildError
 
-  Backend operation failed: CalledProcessError(1, ['pip'])
+  hide the original error
   \
 
-  Error on stdout
+  original error
 """
 
     assert directory_package.source_url is not None