#336 OFFSET must not be negative

AUTHORS

@@ -47,3 +47,4 @@ Patches and Suggestions
 - Ignacy Sokołowski
 - Steven Harms
 - David Lord @davidism
+- Blake Grotewold

docs/api.rst

@@ -49,12 +49,12 @@ Models
 
    .. method:: limit(limit)
 
-      Apply a LIMIT  to the query and return the newly resulting query.
+      Apply a LIMIT to the query and return the newly resulting query.
 
    .. method:: offset(offset)
 
-      Apply an OFFSET  to the query and return the newly resulting
-      query.
+      Apply an OFFSET to the query and return the newly resulting
+      query. If the offset is less than 0, it will defaulted to 0.
 
    .. method:: first()
 

flask_sqlalchemy/__init__.py

@@ -317,8 +317,9 @@ def __init__(self, query, page, per_page, total, items):
         #: the unlimited query object that was used to create this
         #: pagination object.
         self.query = query
-        #: the current page number (1 indexed)
-        self.page = page
+        #: the current page number (1 indexed). if it is lower than 1
+        #: it gets defaulted to 1.
+        self.page = page if page and page > 0 else 1
         #: the number of items to be displayed on a page.
         self.per_page = per_page
         #: the total number of items matching the query
@@ -470,8 +471,11 @@ def paginate(self, page=None, per_page=None, error_out=True):
             if per_page is None:
                 per_page = 20
 
-        if error_out and page < 1:
-            abort(404)
+        if page < 1:
+            if error_out:
+                abort(404)
+            else:
+                page = 1
 
         items = self.limit(per_page).offset((page - 1) * per_page).all()
 

test_sqlalchemy.py

@@ -8,6 +8,7 @@
 from sqlalchemy import MetaData
 from sqlalchemy.ext.declarative import declared_attr
 from sqlalchemy.orm import sessionmaker
+from werkzeug.exceptions import NotFound
 
 
 def make_todo_model(db):
@@ -352,6 +353,14 @@ def test_pagination_pages_when_0_items_per_page(self):
         p = sqlalchemy.Pagination(None, 1, 0, 500, [])
         self.assertEqual(p.pages, 0)
 
+    def test_pagination_page_when_page_number_is_none(self):
+        p = sqlalchemy.Pagination(None, None, 20, 500, [])
+        self.assertEqual(p.page, 1)
+
+    def test_pagination_page_when_page_number_is_negative(self):
+        p = sqlalchemy.Pagination(None, -1, 20, 500, [])
+        self.assertEqual(p.page, 1)
+
     def test_query_paginate(self):
         app = flask.Flask(__name__)
         db = sqlalchemy.SQLAlchemy(app)
@@ -380,6 +389,23 @@ def index():
             p = Todo.query.paginate()
             self.assertEqual(p.total, 100)
 
+    def test_query_paginate_with_negative_page(self):
+        app = flask.Flask(__name__)
+        db = sqlalchemy.SQLAlchemy(app)
+        Todo = make_todo_model(db)
+        db.create_all()
+
+        with app.app_context():
+            db.session.add_all([Todo('', '') for _ in range(100)])
+            db.session.commit()
+
+            # with error_out
+            self.assertRaises(NotFound, lambda: Todo.query.paginate(page=-1))
+
+            # without error_out
+            p = Todo.query.paginate(page=-1, error_out=False)
+            self.assertEqual(p.page, 1)
+
 
 class BindsTestCase(unittest.TestCase):