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Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/BuiltinFunctions.java

@@ -731,6 +731,8 @@ PCode compile(String expression, String filename, String mode, Object kwFlags, O
             ParserMode pm;
             if (mode.equals("exec")) {
                 pm = ParserMode.File;
+                // CPython adds a newline and we need to do the same in order to produce
+                // SyntaxError with the same offset when the line is incomplete
                 if (!code.endsWith("\n")) {
                     code += '\n';
                 }

graalpython/lib-graalpython/sys.py

@@ -185,6 +185,9 @@ def __print_traceback__(typ, value, tb):
         try:
             import traceback
             lines = traceback.format_exception(typ, value, tb)
+            # CPython's C traceback printer diverges from traceback.print_exception in this small detail.
+            # We'd like to contribute to CPython to fix the divergence, but for now we do just
+            # a string substitution to pass the tests
             lines[-1] = lines[-1].replace(f'<unprintable {typ.__name__} object>', f'<exception str() failed>')
             for line in lines:
                 print(line, file=stderr, end="")