From 0ca7b53b4235c2fbabfbb6a4e2df2f7a369df6f2 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Fri, 12 Jul 2013 11:32:34 -0400 Subject: Fixed bug where the expression system relied upon the ``str()`` form of a some expressions when referring to the ``.c`` collection on a ``select()`` construct, but the ``str()`` form isn't available since the element relies on dialect-specific compilation constructs, notably the ``__getitem__()`` operator as used with a Postgresql ``ARRAY`` element. The fix also adds a new exception class :class:`.UnsupportedCompilationError` which is raised in those cases where a compiler is asked to compile something it doesn't know how to. Also in 0.8.3. [ticket:2780] --- lib/sqlalchemy/sql/compiler.py | 8 ++++++-- lib/sqlalchemy/sql/expression.py | 5 ++++- lib/sqlalchemy/sql/visitors.py | 15 +++++++++++++-- 3 files changed, 23 insertions(+), 5 deletions(-) (limited to 'lib/sqlalchemy/sql') diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py index 93dc3fc4d..a5f545de9 100644 --- a/lib/sqlalchemy/sql/compiler.py +++ b/lib/sqlalchemy/sql/compiler.py @@ -696,8 +696,12 @@ class SQLCompiler(engine.Compiled): if disp: return disp(binary, operator, **kw) else: - return self._generate_generic_binary(binary, - OPERATORS[operator], **kw) + try: + opstring = OPERATORS[operator] + except KeyError: + raise exc.UnsupportedCompilationError(self, operator) + else: + return self._generate_generic_binary(binary, opstring, **kw) def visit_custom_op_binary(self, element, operator, **kw): return self._generate_generic_binary(element, diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 6ee110e9c..9e5c4cfcb 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -2360,7 +2360,10 @@ class ColumnElement(ClauseElement, ColumnOperators): """ if name is None: name = self.anon_label - key = str(self) + try: + key = str(self) + except exc.UnsupportedCompilationError: + key = self.anon_label else: key = name co = ColumnClause(_as_truncated(name) if name_is_truncatable else name, diff --git a/lib/sqlalchemy/sql/visitors.py b/lib/sqlalchemy/sql/visitors.py index 24ada8d9f..7b729bf7f 100644 --- a/lib/sqlalchemy/sql/visitors.py +++ b/lib/sqlalchemy/sql/visitors.py @@ -26,6 +26,7 @@ http://techspot.zzzeek.org/2008/01/23/expression-transformations/ from collections import deque from .. import util import operator +from .. import exc __all__ = ['VisitableType', 'Visitable', 'ClauseVisitor', 'CloningVisitor', 'ReplacingCloningVisitor', 'iterate', @@ -70,14 +71,24 @@ def _generate_dispatch(cls): getter = operator.attrgetter("visit_%s" % visit_name) def _compiler_dispatch(self, visitor, **kw): - return getter(visitor)(self, **kw) + try: + meth = getter(visitor) + except AttributeError: + raise exc.UnsupportedCompilationError(visitor, cls) + else: + return meth(self, **kw) else: # The optimization opportunity is lost for this case because the # __visit_name__ is not yet a string. As a result, the visit # string has to be recalculated with each compilation. def _compiler_dispatch(self, visitor, **kw): visit_attr = 'visit_%s' % self.__visit_name__ - return getattr(visitor, visit_attr)(self, **kw) + try: + meth = getattr(visitor, visit_attr) + except AttributeError: + raise exc.UnsupportedCompilationError(visitor, cls) + else: + return meth(self, **kw) _compiler_dispatch.__doc__ = \ """Look for an attribute named "visit_" + self.__visit_name__ -- cgit v1.2.1