- Added support for the case of the misbehaving DBAPI that has

pep-249 exception names linked to exception classes of an entirely
different name, preventing SQLAlchemy's own exception wrapping from
wrapping the error appropriately.
The SQLAlchemy dialect in use needs to implement a new
accessor :attr:`.DefaultDialect.dbapi_exception_translation_map`
to support this feature; this is implemented now for the py-postgresql
dialect.
fixes #3421

1 files changed, 57 insertions, 0 deletions

diff --git a/test/base/test_except.py b/test/base/test_except.py
index 918e7a042..9e8dd4760 100644
--- a/test/base/test_except.py
+++ b/test/base/test_except.py
@@ -4,6 +4,7 @@
 from sqlalchemy import exc as sa_exceptions
 from sqlalchemy.testing import fixtures
 from sqlalchemy.testing import eq_
+from sqlalchemy.engine import default
 
 
 class Error(Exception):
@@ -28,8 +29,28 @@ class OutOfSpec(DatabaseError):
     pass
 
 
+# exception with a totally different name...
+class WrongNameError(DatabaseError):
+    pass
+
+# but they're going to call it their "IntegrityError"
+IntegrityError = WrongNameError
+
+
+# and they're going to subclass it!
+class SpecificIntegrityError(WrongNameError):
+    pass
+
+
 class WrapTest(fixtures.TestBase):
 
+    def _translating_dialect_fixture(self):
+        d = default.DefaultDialect()
+        d.dbapi_exception_translation_map = {
+            "WrongNameError": "IntegrityError"
+        }
+        return d
+
     def test_db_error_normal(self):
         try:
             raise sa_exceptions.DBAPIError.instance(
@@ -160,6 +181,42 @@ class WrapTest(fixtures.TestBase):
         except sa_exceptions.ArgumentError:
             self.assert_(False)
 
+        dialect = self._translating_dialect_fixture()
+        try:
+            raise sa_exceptions.DBAPIError.instance(
+                '', [],
+                sa_exceptions.ArgumentError(), DatabaseError,
+                dialect=dialect)
+        except sa_exceptions.DBAPIError as e:
+            self.assert_(e.__class__ is sa_exceptions.DBAPIError)
+        except sa_exceptions.ArgumentError:
+            self.assert_(False)
+
+    def test_db_error_dbapi_uses_wrong_names(self):
+        dialect = self._translating_dialect_fixture()
+
+        try:
+            raise sa_exceptions.DBAPIError.instance(
+                '', [], IntegrityError(),
+                DatabaseError, dialect=dialect)
+        except sa_exceptions.DBAPIError as e:
+            self.assert_(e.__class__ is sa_exceptions.IntegrityError)
+
+        try:
+            raise sa_exceptions.DBAPIError.instance(
+                '', [], SpecificIntegrityError(),
+                DatabaseError, dialect=dialect)
+        except sa_exceptions.DBAPIError as e:
+            self.assert_(e.__class__ is sa_exceptions.IntegrityError)
+
+        try:
+            raise sa_exceptions.DBAPIError.instance(
+                '', [], SpecificIntegrityError(),
+                DatabaseError)
+        except sa_exceptions.DBAPIError as e:
+            # doesn't work without a dialect
+            self.assert_(e.__class__ is not sa_exceptions.IntegrityError)
+
     def test_db_error_keyboard_interrupt(self):
         try:
             raise sa_exceptions.DBAPIError.instance(