bpo-34463: Make python tracebacks identical to C tracebacks for SyntaxErrors without a lineno (GH-23427)
diff --git a/Lib/traceback.py b/Lib/traceback.py
index 457d925..4e008bc 100644
--- a/Lib/traceback.py
+++ b/Lib/traceback.py
@@ -525,7 +525,8 @@ def __init__(self, exc_type, exc_value, exc_traceback, *, limit=None,
if exc_type and issubclass(exc_type, SyntaxError):
# Handle SyntaxError's specially
self.filename = exc_value.filename
- self.lineno = str(exc_value.lineno)
+ lno = exc_value.lineno
+ self.lineno = str(lno) if lno is not None else None
self.text = exc_value.text
self.offset = exc_value.offset
self.msg = exc_value.msg
@@ -584,9 +585,12 @@ def format_exception_only(self):
def _format_syntax_error(self, stype):
"""Format SyntaxError exceptions (internal helper)."""
# Show exactly where the problem was found.
- filename = self.filename or "<string>"
- lineno = str(self.lineno) or '?'
- yield ' File "{}", line {}\n'.format(filename, lineno)
+ filename_suffix = ''
+ if self.lineno is not None:
+ yield ' File "{}", line {}\n'.format(
+ self.filename or "<string>", self.lineno)
+ elif self.filename is not None:
+ filename_suffix = ' ({})'.format(self.filename)
text = self.text
if text is not None:
@@ -604,7 +608,7 @@ def _format_syntax_error(self, stype):
caretspace = ((c if c.isspace() else ' ') for c in ltext[:caret])
yield ' {}^\n'.format(''.join(caretspace))
msg = self.msg or "<no detail available>"
- yield "{}: {}\n".format(stype, msg)
+ yield "{}: {}{}\n".format(stype, msg, filename_suffix)
def format(self, *, chain=True):
"""Format the exception.