From: Mike Bayer Date: Fri, 12 Jul 2013 15:32:34 +0000 (-0400) Subject: Fixed bug where the expression system relied upon the ``str()`` X-Git-Tag: rel_0_9_0b1~184 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0ca7b53b4235c2fbabfbb6a4e2df2f7a369df6f2;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git 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] --- diff --git a/doc/build/changelog/changelog_08.rst b/doc/build/changelog/changelog_08.rst index 5c03b9007d..8ec248b893 100644 --- a/doc/build/changelog/changelog_08.rst +++ b/doc/build/changelog/changelog_08.rst @@ -6,6 +6,22 @@ .. changelog:: :version: 0.8.3 + .. change:: + :tags: bug, sql, postgresql + :tickets: 2780 + + 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. + + .. change:: + :tags: bug, engine, oracle :tickets: 2776 Dialect.initialize() is not called a second time if an :class:`.Engine` diff --git a/doc/build/changelog/changelog_09.rst b/doc/build/changelog/changelog_09.rst index 4eab720e0a..b1966f899e 100644 --- a/doc/build/changelog/changelog_09.rst +++ b/doc/build/changelog/changelog_09.rst @@ -6,6 +6,20 @@ .. changelog:: :version: 0.9.0 + .. change:: + :tags: bug, sql, postgresql + :tickets: 2780 + + 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. + .. change:: :tags: bug, engine, oracle :tickets: 2776 diff --git a/lib/sqlalchemy/exc.py b/lib/sqlalchemy/exc.py index f5dc1119dc..cfd1e2bc7b 100644 --- a/lib/sqlalchemy/exc.py +++ b/lib/sqlalchemy/exc.py @@ -72,6 +72,18 @@ class CircularDependencyError(SQLAlchemyError): class CompileError(SQLAlchemyError): """Raised when an error occurs during SQL compilation""" +class UnsupportedCompilationError(CompileError): + """Raised when an operation is not supported by the given compiler. + + + .. versionadded:: 0.8.3 + + """ + + def __init__(self, compiler, element_type): + super(UnsupportedCompilationError, self).__init__( + "Compiler %r can't render element of type %s" % + (compiler, element_type)) class IdentifierError(SQLAlchemyError): """Raised when a schema name is beyond the max character limit""" diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py index 93dc3fc4d0..a5f545de9a 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 6ee110e9c4..9e5c4cfcb6 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 24ada8d9f2..7b729bf7f8 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__ diff --git a/test/sql/test_compiler.py b/test/sql/test_compiler.py index 8b9f9cfa49..bdfcccb22e 100644 --- a/test/sql/test_compiler.py +++ b/test/sql/test_compiler.py @@ -2482,6 +2482,46 @@ class SelectTest(fixtures.TestBase, AssertsCompiledSQL): ) +class UnsupportedTest(fixtures.TestBase): + def test_unsupported_element_str_visit_name(self): + from sqlalchemy.sql.expression import ClauseElement + class SomeElement(ClauseElement): + __visit_name__ = 'some_element' + + assert_raises_message( + exc.UnsupportedCompilationError, + r"Compiler ", + SomeElement().compile + ) + + def test_unsupported_element_meth_visit_name(self): + from sqlalchemy.sql.expression import ClauseElement + class SomeElement(ClauseElement): + @classmethod + def __visit_name__(cls): + return "some_element" + + assert_raises_message( + exc.UnsupportedCompilationError, + r"Compiler ", + SomeElement().compile + ) + + def test_unsupported_operator(self): + from sqlalchemy.sql.expression import BinaryExpression + def myop(x, y): + pass + binary = BinaryExpression(column("foo"), column("bar"), myop) + assert_raises_message( + exc.UnsupportedCompilationError, + r"Compiler