Error when printing exclusion constraint with operator explicitly specifying schema

[bennieswart]

Consider the following code:

import pglast
sql = "ALTER TABLE T ADD CONSTRAINT C EXCLUDE USING gist (F WITH OPERATOR(intarray.&&))"
print(pglast.prettify(sql))

which produces the following error:

Traceback (most recent call last):
  File "format.py", line 3, in <module>
    print(pglast.prettify(sql))
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/__init__.py", line 46, in prettify
    prettified = IndentedStream(**options)(Node(orig_pt))
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 251, in __call__
    self.print_node(statement)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 380, in print_node
    printer(node, self)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printers/dml.py", line 701, in raw_stmt
    output.print_node(node.stmt)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 380, in print_node
    printer(node, self)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printers/ddl.py", line 252, in alter_table_stmt
    output.print_list(node.cmds, ',', standalone_items=True)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 598, in print_list
    super().print_list(nodes, sep, relative_indent, standalone_items, are_names, is_symbol)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 437, in print_list
    is_symbol=is_symbol)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 401, in _print_items
    self.print_node(item, is_name=are_names, is_symbol=is_symbol and idx == last)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 380, in print_node
    printer(node, self)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printers/ddl.py", line 284, in alter_table_cmd
    output.print_node(constraint)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printer.py", line 380, in print_node
    printer(node, self)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/printers/ddl.py", line 488, in constraint
    output.write(clauses.string_value)
  File "~/.pyenv/versions/3.5.2/lib/python3.5/site-packages/pglast/node.py", line 143, in string_value
    raise TypeError('%r does not contain a single String node' % self)
TypeError: [2*{String}] does not contain a single String node

This is almost certainly due to the && operator explicitly specifying the schema, that is, intarray.&&.
Version used is pglast 1.17 on python 3.5.2.

[lelit]

Thank you for the report, I can see the same problem in v3. I will try to address the problem as soon as possible, but only on the latter version.

[lelit]

As the fix was so simple, I changed my mind and applied it on v1 and merged in v3.

[lelit]

I released v1.18 with the fix.

[bennieswart]

Thanks, great job!