From a1fe6e2c7607740c46eaab89e2bcd70aaccee71e Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Wed, 20 Jun 2007 22:28:54 +0000
Subject: [PATCH] - forwards-compatibility with 0.4: added one(), first(), and
 all() to Query - added selectone_by() to assignmapper

---
 CHANGES                            |  6 +++-
 lib/sqlalchemy/ext/assignmapper.py |  2 +-
 lib/sqlalchemy/orm/query.py        | 45 ++++++++++++++++++++++++++++--
 test/orm/inheritance5.py           |  2 ++
 4 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/CHANGES b/CHANGES
index 393c6a2882..5e3f960d01 100644
--- a/CHANGES
+++ b/CHANGES
@@ -8,6 +8,8 @@
     - association proxies no longer bind tightly to source collections
       [ticket:597], and are constructed with a thunk instead
 - orm
+    - forwards-compatibility with 0.4: added one(), first(), and 
+      all() to Query
     - added synchronization to the mapper() construction step, to avoid
       thread collections when pre-existing mappers are compiling in a 
       different thread [ticket:613]
@@ -42,7 +44,9 @@
     - sqlite better handles datetime/date/time objects mixed and matched
       with various Date/Time/DateTime columns
     - string PK column inserts dont get overwritten with OID [ticket:603] 
-
+- extensions
+    - added selectone_by() to assignmapper
+    
 0.3.8
 - engines
     - added detach() to Connection, allows underlying DBAPI connection
diff --git a/lib/sqlalchemy/ext/assignmapper.py b/lib/sqlalchemy/ext/assignmapper.py
index b124de8f6d..4708afd8dd 100644
--- a/lib/sqlalchemy/ext/assignmapper.py
+++ b/lib/sqlalchemy/ext/assignmapper.py
@@ -43,7 +43,7 @@ def assign_mapper(ctx, class_, *args, **kwargs):
     m = mapper(class_, extension=extension, *args, **kwargs)
     class_.mapper = m
     class_.query = classmethod(lambda cls: Query(class_, session=ctx.current))
-    for name in ['get', 'filter', 'filter_by', 'select', 'select_by', 'selectfirst', 'selectfirst_by', 'selectone', 'get_by', 'join_to', 'join_via', 'count', 'count_by', 'options', 'instances']:
+    for name in ['get', 'filter', 'filter_by', 'select', 'select_by', 'selectfirst', 'selectfirst_by', 'selectone', 'selectone_by', 'get_by', 'join_to', 'join_via', 'count', 'count_by', 'options', 'instances']:
         monkeypatch_query_method(ctx, class_, name)
     for name in ['flush', 'delete', 'expire', 'refresh', 'expunge', 'merge', 'save', 'update', 'save_or_update']:
         monkeypatch_objectstore_method(ctx, class_, name)
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 2266f9fa8d..c29933ef93 100644
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -828,15 +828,56 @@ class Query(object):
 
         return list(self)
 
-    def scalar(self):
+    def one(self):
+        """Return the first result of this ``Query``, raising an exception if more than one row exists.
+
+        This results in an execution of the underlying query.
+        
+        this method is for forwards-compatibility with 0.4.
+        """
+
+        if self._col is None or self._func is None: 
+            ret = list(self[0:2])
+
+            if len(ret) == 1:
+                return ret[0]
+            elif len(ret) == 0:
+                raise exceptions.InvalidRequestError('No rows returned for one()')
+            else:
+                raise exceptions.InvalidRequestError('Multiple rows returned for one()')
+        else:
+            return self._col_aggregate(self._col, self._func)
+
+    def first(self):
         """Return the first result of this ``Query``.
 
         This results in an execution of the underlying query.
+
+        this method is for forwards-compatibility with 0.4.
         """
+
         if self._col is None or self._func is None: 
-            return self[0]
+            ret = list(self[0:1])
+            if len(ret) > 0:
+                return ret[0]
+            else:
+                return None
         else:
             return self._col_aggregate(self._col, self._func)
+
+    def all(self):
+        return self.list()
+
+    def scalar(self):
+        """Return the first result of this ``Query``.
+
+        This results in an execution of the underlying query.
+        
+        this method will be deprecated in 0.4; first() is added for 
+        forwards-compatibility.
+        """
+        
+        return self.first()
     
     def __iter__(self):
         return iter(self.select_whereclause())
diff --git a/test/orm/inheritance5.py b/test/orm/inheritance5.py
index 56a83f5757..b0a905f339 100644
--- a/test/orm/inheritance5.py
+++ b/test/orm/inheritance5.py
@@ -843,9 +843,11 @@ class CustomPKTest(testbase.ORMTest):
             Column('id', Integer, primary_key=True),
             Column('type', String(30), nullable=False),
             Column('data', String(30)))
+        # note that the primary key column in t2 is named differently
         t2 = Table('t2', metadata,
             Column('t2id', Integer, ForeignKey('t1.id'), primary_key=True),
             Column('t2data', String(30)))
+            
     def test_custompk(self):
         """test that the primary_key attribute is propigated to the polymorphic mapper"""
         
-- 
2.47.2