added warning that POST cannot be redirected when appending slash

pecan/core.py

@@ -137,6 +137,8 @@ class Pecan(object):
             return node, remainder
         except NonCanonicalPath, e:
             if self.force_canonical and not _cfg(e.controller).get('accept_noncanonical', False):
+                if request.method == 'POST':
+                    raise RuntimeError, "You have POSTed to a URL '%s' which requires a slash.  Most browsers will not maintain POST data when redirected.  Please update you code to POST to '%s/' or set force_canonical to False" % (request.routing_path, request.routing_path)
                 raise exc.HTTPFound(add_slash=True)
             return e.controller, e.remainder
     

tests/test_base.py

@@ -693,6 +693,13 @@ class TestEngines(object):
         r = app.get('/sub', status=302)
         assert r.status_int == 302
 
+        try:
+            r = app.post('/sub', dict(foo=1))
+            raise Exception, "Post should fail"
+        except Exception, e:
+            raise e
+            assert isinstance(e, RuntimeError)
+
         r = app.get('/arg/index/foo')
         assert r.status_int == 200
         assert r.body == 'foo'
@@ -714,6 +721,10 @@ class TestEngines(object):
         assert r.status_int == 200
         assert 'subindex' in r.body
 
+        r = app.post('/sub', dict(foo=1))
+        assert r.status_int == 200
+        assert 'subindex' in r.body
+
         r = app.get('/sub/')
         assert r.status_int == 200
         assert 'subindex' in r.body