fix addmarker - extract mark from markdecorator

src/_pytest/nodes.py

@@ -173,10 +173,12 @@ def listchain(self):
         chain.reverse()
         return chain
 
-    def add_marker(self, marker):
+    def add_marker(self, marker, append=True):
         """dynamically add a marker object to the node.
 
         :type marker: str or pytest.mark.*
+        ``append=True`` whether to append the marker,
+            if false insert at position 0
         """
         from _pytest.mark import MarkDecorator, MARK_GEN
 
@@ -185,7 +187,10 @@ def add_marker(self, marker):
         elif not isinstance(marker, MarkDecorator):
             raise ValueError("is not a string or pytest.mark.* Marker")
         self.keywords[marker.name] = marker
-        self.own_markers.append(marker.mark)
+        if append:
+            self.own_markers.append(marker.mark)
+        else:
+            self.own_markers.insert(0, marker.mark)
 
     def iter_markers(self, name=None):
         """

testing/test_mark.py

@@ -1132,3 +1132,12 @@ def test_addmarker_getmarker():
     node.add_marker("b")
     node.get_marker("a").combined
     node.get_marker("b").combined
+
+
+def test_addmarker_order():
+    node = Node("Test", config=mock.Mock(), session=mock.Mock(), nodeid="Test")
+    node.add_marker("a")
+    node.add_marker("b")
+    node.add_marker("c", append=False)
+    extracted = [x.name for x in node.iter_markers()]
+    assert extracted == ["c", "a", "b"]