Problem

Django 6.0 introduced a breaking change requiring as_sql() methods to return params as a tuple, not a list.

From Django 6.0 Release Notes:

Prior to Django 6.0, custom lookups and custom expressions implementing the as_sql() method (and its supporting methods process_lhs() and process_rhs()) were allowed to return a sequence of params in either a list or a tuple. To address the interoperability problems that resulted, the second return element of the as_sql() method should now be a tuple.

Current Behavior

In psqlextra/expressions.py, several as_sql() methods return lists:

HStoreValue.as_sql (line 61)

return " || ".join(sql), params  # params is a list

HStoreColumn.as_sql (line 106)

return (
    "%s.%s->'%s'"
    % (qn(self.alias), qn(self.target.column), self.hstore_key),
    [],  # returns empty list
)

Note: ExcludedCol.as_sql (line 223) correctly uses tuple().

Error

When using LocalizedField (from django-localized-fields) with Django 6.0:

psycopg2.ProgrammingError: can't adapt type 'dict'

This occurs during ORM operations that trigger HStore field handling.

Expected Behavior

All as_sql() methods should return params as tuple:

# HStoreValue.as_sql
return " || ".join(sql), tuple(params)

# HStoreColumn.as_sql  
return (..., ())

Environment

• Django 6.0
• django-postgres-extra: 2.0.4, 2.0.9, 3.0.0rc1 (all affected)
• Python 3.12

Related

• Issue Django 5.0 support #232 (Django 5.0 support)
• Django 6.0 Release Notes - as_sql() change