Failed to recognize trailing comma on import statement with parenthese

[williamjamir]

Hi,

Trailing comma is not allowed in import, but when inside parentheses it's valid syntax
I know that this one can sound too specific, but still a valid syntax =)

file:

from foo.a import (do,)

do()

Script:

import pasta
from pasta.augment import rename

path = r'test.py'


with open(path) as file:
    tree = pasta.parse(file.read())

Full stack trace

Traceback (most recent call last):
  File "script.py", line 8, in <module>
    tree = pasta.parse(file.read())
  File "/opt/pasta/pasta/__init__.py", line 25, in parse
    annotator.visit(t)
  File "/opt/pasta/pasta/base/annotate.py", line 1055, in visit
    super(AstAnnotator, self).visit(node)
  File "/opt/pasta/pasta/base/annotate.py", line 115, in visit
    super(BaseVisitor, self).visit(node)
  File "/home/william/miniconda3/envs/google_pasta_py27/lib/python2.7/ast.py", line 241, in visit
    return visitor(node)
  File "/opt/pasta/pasta/base/annotate.py", line 79, in wrapped
    f(self, node, *args, **kwargs)
  File "/opt/pasta/pasta/base/annotate.py", line 168, in visit_Module
    self.generic_visit(node)
  File "/home/william/miniconda3/envs/google_pasta_py27/lib/python2.7/ast.py", line 249, in generic_visit
    self.visit(item)
  File "/opt/pasta/pasta/base/annotate.py", line 1055, in visit
    super(AstAnnotator, self).visit(node)
  File "/opt/pasta/pasta/base/annotate.py", line 115, in visit
    super(BaseVisitor, self).visit(node)
  File "/home/william/miniconda3/envs/google_pasta_py27/lib/python2.7/ast.py", line 241, in visit
    return visitor(node)
  File "/opt/pasta/pasta/base/annotate.py", line 43, in wrapped
    f(self, node, *args, **kwargs)
  File "/opt/pasta/pasta/base/annotate.py", line 520, in visit_Expr
    self.visit(node.value)
  File "/opt/pasta/pasta/base/annotate.py", line 1055, in visit
    super(AstAnnotator, self).visit(node)
  File "/opt/pasta/pasta/base/annotate.py", line 115, in visit
    super(BaseVisitor, self).visit(node)
  File "/home/william/miniconda3/envs/google_pasta_py27/lib/python2.7/ast.py", line 241, in visit
    return visitor(node)
  File "/opt/pasta/pasta/base/annotate.py", line 43, in wrapped
    f(self, node, *args, **kwargs)
  File "/opt/pasta/pasta/base/annotate.py", line 637, in visit_Call
    self.visit(node.func)
  File "/opt/pasta/pasta/base/annotate.py", line 1055, in visit
    super(AstAnnotator, self).visit(node)
  File "/opt/pasta/pasta/base/annotate.py", line 115, in visit
    super(BaseVisitor, self).visit(node)
  File "/home/william/miniconda3/envs/google_pasta_py27/lib/python2.7/ast.py", line 241, in visit
    return visitor(node)
  File "/opt/pasta/pasta/base/annotate.py", line 43, in wrapped
    f(self, node, *args, **kwargs)
  File "/opt/pasta/pasta/base/annotate.py", line 754, in visit_Name
    self.token(node.id)
  File "/opt/pasta/pasta/base/annotate.py", line 1118, in token
    token_val, token.src, token.start[0], token.line))
pasta.base.annotate.AnnotationError: Expected 'do' but found ','
line 1: from foo.a import (do,)

cc @nicoddemus

[soupytwist]

Thanks for finding and reporting all these corner cases :)

This can probably be added to a generalized function as well.