[vscode] Report the origin of an unexpected exception during validation (#18494)

esphome/vscode.py

@@ -3,12 +3,14 @@ from __future__ import annotations
 from io import StringIO
 import json
 from pathlib import Path
+import sys
+import traceback
 from typing import Any
 
 from esphome.config import Config, _format_vol_invalid, validate_config
 import esphome.config_validation as cv
 from esphome.const import __version__ as ESPHOME_VERSION
-from esphome.core import CORE, DocumentRange
+from esphome.core import CORE, DocumentRange, EsphomeError
 from esphome.yaml_util import parse_yaml
 
 
@@ -97,6 +99,16 @@ def _ace_loader(fname: Path) -> dict[str, Any]:
     return parse_yaml(fname, raw_yaml_stream)
 
 
+def _format_unexpected_error(err: Exception) -> str:
+    """Describe a crash inside validation with the frame it came from."""
+    message = f"Unexpected error while validating: {type(err).__name__}: {err}"
+    frames = traceback.extract_tb(err.__traceback__)
+    if not frames:
+        return message
+    frame = frames[-1]
+    return f"{message} ({frame.filename}:{frame.lineno} in {frame.name})"
+
+
 def _print_version():
     """Print ESPHome version."""
     print(
@@ -134,8 +146,12 @@ def read_config(args):
         try:
             config = loader(file_name)
             res = validate_config(config, command_line_substitutions)
-        except Exception as err:  # noqa: BLE001  # pylint: disable=broad-except
+        except (EsphomeError, cv.Invalid) as err:
             vs.add_yaml_error(str(err))
+        except Exception as err:  # noqa: BLE001  # pylint: disable=broad-except
+            # stdout carries the JSON protocol; the full chain goes to stderr.
+            traceback.print_exc(file=sys.stderr)
+            vs.add_yaml_error(_format_unexpected_error(err))
         else:
             for err in res.errors:
                 try:

tests/unit_tests/test_vscode.py

@@ -3,6 +3,8 @@ from pathlib import Path
 from unittest.mock import Mock, patch
 
 from esphome import vscode
+import esphome.config_validation as cv
+from esphome.core import EsphomeError
 
 
 def _run_repl_test(input_data):
@@ -126,3 +128,67 @@ packages:
     assert range["start_col"] == 2
     assert range["end_line"] == 1
     assert range["end_col"] == 7
+
+
+def _explode(*_args: object, **_kwargs: object) -> None:
+    raise AttributeError("'NoneType' object has no attribute 'get'")
+
+
+def test_unexpected_error_reports_origin() -> None:
+    source_path = str(Path("dir_path", "x.yaml"))
+    with patch("esphome.vscode.validate_config", _explode):
+        output_lines = _run_repl_test(
+            [
+                _validate(source_path),
+                _file_response("""esphome:
+  name: test1
+"""),
+            ]
+        )
+
+    result = json.loads(output_lines[-1])
+    assert result["validation_errors"] == []
+    (error,) = result["yaml_errors"]
+    assert error["message"].startswith(
+        "Unexpected error while validating: AttributeError: "
+        "'NoneType' object has no attribute 'get' ("
+    )
+    assert "test_vscode.py" in error["message"]
+    assert error["message"].endswith(" in _explode)")
+
+
+def test_esphome_error_stays_plain() -> None:
+    source_path = str(Path("dir_path", "x.yaml"))
+    with patch("esphome.vscode.validate_config", side_effect=EsphomeError("boom")):
+        output_lines = _run_repl_test(
+            [
+                _validate(source_path),
+                _file_response("""esphome:
+  name: test1
+"""),
+            ]
+        )
+
+    result = json.loads(output_lines[-1])
+    assert result["yaml_errors"] == [{"message": "boom"}]
+
+
+def test_invalid_stays_plain() -> None:
+    source_path = str(Path("dir_path", "x.yaml"))
+    with patch("esphome.vscode.validate_config", side_effect=cv.Invalid("bad value")):
+        output_lines = _run_repl_test(
+            [
+                _validate(source_path),
+                _file_response("""esphome:
+  name: test1
+"""),
+            ]
+        )
+
+    result = json.loads(output_lines[-1])
+    assert result["yaml_errors"] == [{"message": "bad value"}]
+
+
+def test_format_unexpected_error_without_traceback() -> None:
+    message = vscode._format_unexpected_error(ValueError("boom"))
+    assert message == "Unexpected error while validating: ValueError: boom"