Refactor crash handling in pylinter and add tests

pylint/lint/pylinter.py

@@ -3,7 +3,6 @@
 
 import collections
 import contextlib
-import datetime
 import functools
 import operator
 import os
@@ -12,7 +11,6 @@
 import traceback
 import warnings
 from io import TextIOWrapper
-from pathlib import Path
 
 import astroid
 from astroid import AstroidError
@@ -26,7 +24,11 @@
     report_messages_stats,
     report_total_messages_stats,
 )
-from pylint.lint.utils import fix_import_path
+from pylint.lint.utils import (
+    fix_import_path,
+    get_fatal_error_message,
+    prepare_crash_report,
+)
 from pylint.message import MessageDefinitionStore, MessagesHandlerMixIn
 from pylint.reporters.ureports import nodes as report_nodes
 from pylint.utils import ASTWalker, FileState, utils
@@ -1006,51 +1008,6 @@ def check_single_file(self, name, filepath, modname):
                 self.get_ast, check_astroid_module, name, filepath, modname
             )
 
-    @staticmethod
-    def _prepare_crash_report(ex: Exception, filepath: str) -> str:
-        now = datetime.datetime.now().strftime("%Y-%m-%d-%H")
-        issue_template_path = Path(f"pylint-crash-{now}.txt")
-        with open(filepath, encoding="utf8") as f:
-            file_content = f.read()
-        template = ""
-        if not issue_template_path.exists():
-            template = """\
-First, please verify that the bug is not already filled:
-https://github.com/PyCQA/pylint/issues/
-
-Then create a new crash issue:
-https://github.com/PyCQA/pylint/issues/new?assignees=&labels=crash%2Cneeds+triage&template=BUG-REPORT.yml
-
-"""
-        template += f"""\
-
-Issue title:
-Crash ``{ex}`` (if possible, be more specific about what made pylint crash)
-Content:
-When parsing the following file:
-
-<!--
- If sharing the code is not an option, please state so,
- but providing only the stacktrace would still be helpful.
- -->
-
-```python
-{file_content}
-```
-
-pylint crashed with a {ex.__class__.__name__} with the following stacktrace:
-```
-"""
-        with open(issue_template_path, "a", encoding="utf8") as f:
-            f.write(template)
-            traceback.print_exc(file=f)
-            f.write("\n```\n")
-        return (
-            f"Fatal error while checking '{filepath}'. "
-            f"Please open an issue in our bug tracker so we address this. "
-            f"There is a pre-filled template that you can use in '{issue_template_path}'."
-        )
-
     def _check_files(self, get_ast, file_descrs):
         """Check all files from file_descrs
 
@@ -1062,19 +1019,24 @@ def _check_files(self, get_ast, file_descrs):
         """
         with self._astroid_module_checker() as check_astroid_module:
             for name, filepath, modname in file_descrs:
+                error = None
                 try:
                     self._check_file(
                         get_ast, check_astroid_module, name, filepath, modname
                     )
-                except AstroidError as ex:
-                    self.add_message(
-                        "astroid-error",
-                        args=(filepath, self._prepare_crash_report(ex, filepath)),
-                    )
                 except Exception as ex:  # pylint: disable=broad-except
-                    self.add_message(
-                        "fatal", args=self._prepare_crash_report(ex, filepath)
+                    error = ex
+                    template_path = prepare_crash_report(
+                        error, filepath, "pylint-crash-"
                     )
+                if error is not None:
+                    msg = get_fatal_error_message(filepath, template_path)
+                    if isinstance(error, AstroidError):
+                        symbol = "astroid-error"
+                        msg = (filepath, msg)
+                    else:
+                        symbol = "fatal"
+                    self.add_message(symbol, args=msg)
 
     def _check_file(self, get_ast, check_astroid_module, name, filepath, modname):
         """Check a file using the passed utility functions (get_ast and check_astroid_module)

pylint/lint/utils.py

@@ -3,6 +3,9 @@
 
 import contextlib
 import sys
+import traceback
+from datetime import datetime
+from pathlib import Path
 
 from pylint.lint.expand_modules import get_python_path
 
@@ -11,6 +14,55 @@ class ArgumentPreprocessingError(Exception):
     """Raised if an error occurs during argument preprocessing."""
 
 
+def prepare_crash_report(ex: Exception, filepath: str, crash_file_prefix: str) -> Path:
+    now = datetime.now().strftime("%Y-%m-%d-%H")
+    issue_template_path = Path(f"{crash_file_prefix}{now}.txt").resolve()
+    with open(filepath, encoding="utf8") as f:
+        file_content = f.read()
+    template = ""
+    if not issue_template_path.exists():
+        template = """\
+First, please verify that the bug is not already filled:
+https://github.com/PyCQA/pylint/issues/
+
+Then create a new crash issue:
+https://github.com/PyCQA/pylint/issues/new?assignees=&labels=crash%2Cneeds+triage&template=BUG-REPORT.yml
+
+"""
+    template += f"""\
+
+Issue title:
+Crash ``{ex}`` (if possible, be more specific about what made pylint crash)
+Content:
+When parsing the following file:
+
+<!--
+ If sharing the code is not an option, please state so,
+ but providing only the stacktrace would still be helpful.
+ -->
+
+```python
+{file_content}
+```
+
+pylint crashed with a ``{ex.__class__.__name__}`` and with the following stacktrace:
+```
+"""
+    with open(issue_template_path, "a", encoding="utf8") as f:
+        f.write(template)
+        traceback.print_exc(file=f)
+        f.write("```\n")
+    return issue_template_path
+
+
+def get_fatal_error_message(filepath: str, issue_template_path: Path) -> str:
+    return (
+        f"Fatal error while checking '{filepath}'. "
+        f"Please open an issue in our bug tracker so we address this. "
+        f"There is a pre-filled template that you can use in '{issue_template_path}'."
+    )
+
+
 def preprocess_options(args, search_for):
     """look for some options (keys of <search_for>) which have to be processed
     before others

tests/lint/test_utils.py

@@ -0,0 +1,29 @@
+from pylint.lint.utils import get_fatal_error_message, prepare_crash_report
+
+
+def test_prepare_crash_report(tmp_path):
+    exception_content = "Exmessage"
+    python_file = tmp_path / "myfile.py"
+    python_content = "from shadok import MagicFaucet"
+    with open(python_file, "w", encoding="utf8") as f:
+        f.write(python_content)
+    try:
+        raise Exception(exception_content)
+    except Exception as ex:  # pylint: disable=broad-except
+        template_path = prepare_crash_report(ex, python_file, tmp_path)
+    assert str(tmp_path) in str(template_path)
+    with open(template_path, encoding="utf8") as f:
+        template_content = f.read()
+    assert python_content in template_content
+    assert exception_content in template_content
+    assert "in test_prepare_crash_report" in template_content
+    assert "raise Exception(exception_content)" in template_content
+
+
+def test_get_fatal_error_message():
+    python_path = "mypath.py"
+    crash_path = "crash.txt"
+    msg = get_fatal_error_message(python_path, crash_path)
+    assert python_path in msg
+    assert crash_path in msg
+    assert "open an issue" in msg