From a1dde7eff9a0d44e057afb556d6eba697482c573 Mon Sep 17 00:00:00 2001
From: Manel Clos <manel.clos@ajgirona.cat>
Date: Tue, 25 Sep 2012 10:51:49 +0200
Subject: [PATCH] Query tolerance test

---
 tests/python_tests/query_tolerance_test.py | 43 ++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 tests/python_tests/query_tolerance_test.py

diff --git a/tests/python_tests/query_tolerance_test.py b/tests/python_tests/query_tolerance_test.py
new file mode 100644
index 000000000..160efb05f
--- /dev/null
+++ b/tests/python_tests/query_tolerance_test.py
@@ -0,0 +1,43 @@
+#!/usr/bin/env python
+
+from nose.tools import *
+from utilities import execution_path
+
+import os, mapnik
+
+def setup():
+    # All of the paths used are relative, if we run the tests
+    # from another directory we need to chdir()
+    os.chdir(execution_path('.'))
+
+def test_query_tolerance():
+    srs = '+init=epsg:4326'
+    lyr = mapnik.Layer('test')
+    lyr.datasource = mapnik.Shapefile(file='../data/shp/arrows.shp')
+    lyr.srs = srs
+    _width = 256
+    _map = mapnik.Map(_width,_width, srs)
+    _map.layers.append(lyr)
+    
+    # zoom determines tolerance
+    _map.zoom_all()
+    _map_env = _map.envelope()
+    tol = (_map_env.maxx - _map_env.minx) / _width * 3
+    # 0.046875 for arrows.shp and zoom_all
+    assert tol == 0.046875
+
+    # check point really exists
+    x, y = 2.0, 4.0
+    features = _map.query_point(0,x,y).features
+    assert len(features) == 1
+
+    # check inside tolerance limit
+    x = 2.0 + tol * 0.9
+    features = _map.query_point(0,x,y).features
+    assert len(features) == 1
+
+    # check outside tolerance limit
+    x = 2.0 + tol * 1.1
+    features = _map.query_point(0,x,y).features
+    assert len(features) == 0
+