Parse error for Long octal literals in ast27 #26

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1. ddfisher commented on Jan 27, 2017

   

   ddfisher

   on Jan 27, 2017

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   011111111111111111111111 also fails.

   Here's why: Numbers are parsed in the parsenumber function in ast27/Python/ast.c. In two different circumstances, parsenumber calls PyLong_FromString to do the parsing:

   1. If the number ends with an 'l' or an 'L', we strip the final character (as Python 3 doesn't allow it) and pass it to PyLong_FromString.
   2. If the number is too large to be parsed by strtol (or there's some other error when we try parsing it with strtol), we pass it to PyLong_FromString.
      Unfortunately, Python 3 doesn't support the 01 octal syntax; it has to be 0o1 instead. Hence the error.
2. gvanrossum commented on Jan 27, 2017

   

   gvanrossum

   on Jan 27, 2017

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   You can pre-scan the number to determine the base and pass a base of 8 to PyLong_FromString.
3. ddfisher commented on Jan 27, 2017

   

   ddfisher

   on Jan 27, 2017

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   That's a great idea. Thanks!
4. gvanrossum

   closed this as completedin #28on Jan 27, 2017
5. gvanrossum

   added a commit that references this issue on Jan 27, 2017

   Fix parsing of old style octals in ast27 (#28)

   ...

   This issue will close once commit f72d7f3 is merged into the 'master' branch.

   f72d7f3