Remove "permissions" control in Graph class

src/graph_tool/__init__.py

@@ -1621,10 +1621,6 @@ class Graph(object):
             # directedness is always a filter
             self.set_directed(g.is_directed())
 
-        # modification permissions
-        self.__perms = {"add_edge": True, "del_edge": True,
-                        "add_vertex": True, "del_vertex": True}
-
     def copy(self):
         """Return a deep copy of self. All :ref:`internal property maps <sec_internal_props>`
         are also copied."""
@@ -1655,10 +1651,6 @@ class Graph(object):
     # Graph access
     # ============
 
-    def __check_perms(self, ptype):
-        if not self.__perms[ptype]:
-            raise RuntimeError("the graph cannot be modified at this point!")
-
     def vertices(self):
         """Return an :meth:`iterator <iterator.__iter__>` over the vertices.
 
@@ -1759,7 +1751,6 @@ class Graph(object):
         if n == 0:
             return (None for i in range(0, 0))
 
-        self.__check_perms("add_vertex")
         v = libcore.add_vertex(self.__graph, n)
 
         vfilt = self.get_vertex_filter()
@@ -1815,8 +1806,6 @@ class Graph(object):
            the graph will no longer be the same.
 
         """
-        self.__check_perms("del_vertex")
-
         try:
             vs = numpy.array([int(vertex)], dtype="int64")
         except TypeError:
@@ -1862,7 +1851,6 @@ class Graph(object):
         in the graph if they don't yet exist.
 
         """
-        self.__check_perms("add_edge")
         e = libcore.add_edge(self.__graph,
                              self.vertex(int(source), add_missing=add_missing),
                              self.vertex(int(target), add_missing=add_missing))
@@ -1887,7 +1875,6 @@ class Graph(object):
            unchanged, unless :meth:`~Graph.set_fast_edge_removal` is set to
            `True`, in which case it can change.
         """
-        self.__check_perms("del_edge")
         return libcore.remove_edge(self.__graph, edge)
 
     def add_edge_list(self, edge_list, hashed=False, string_vals=False,
@@ -1911,7 +1898,6 @@ class Graph(object):
         If given, ``eprops`` specifies edge property maps that will be filled
         with the remaining values at each row, if there are more than two.
         """
-        self.__check_perms("add_edge")
         if eprops is None:
             eprops = ()
         else:
@@ -1954,13 +1940,10 @@ class Graph(object):
 
     def clear(self):
         """Remove all vertices and edges from the graph."""
-        self.__check_perms("del_vertex")
-        self.__check_perms("del_edge")
         self.__graph.Clear()
 
     def clear_edges(self):
         """Remove all edges from the graph."""
-        self.__check_perms("del_edge")
         self.__graph.ClearEdges()
 
     # Internal property maps

src/graph_tool/search/__init__.py

@@ -97,36 +97,6 @@ __all__ = ["bfs_search", "BFSVisitor", "dfs_search", "DFSVisitor",
            "StopSearch"]
 
 
-class VisitorWrapper(object):
-    def __init__(self, g, visitor, edge_members, vertex_members):
-        self.visitor = visitor
-        self.g = g
-        self.edge_members = set(edge_members)
-        self.vertex_members = set(vertex_members)
-
-    def __getattr__(self, attr):
-        try:
-            orig_attr = self.visitor.__getattribute__(attr)
-        except AttributeError:
-            return object.__getattribute__(self, attr)
-        if callable(orig_attr):
-            def wrapped_visitor_member(*args, **kwargs):
-                old_perms = dict(self.g._Graph__perms)
-                perms ={"del_vertex": False, "del_edge": False, "add_edge": False}
-                if attr in self.edge_members:
-                    perms.update({"del_edge": True, "add_edge": True})
-                elif attr in self.vertex_members:
-                    perms.update({"add_vertex": False})
-                self.g._Graph__perms.update(perms)
-                try:
-                    ret = orig_attr(*args, **kwargs)
-                finally:
-                    self.g._Graph__perms.update(old_perms)
-                return ret
-            return wrapped_visitor_member
-        else:
-            return orig_attr
-
 class BFSVisitor(object):
     r"""A visitor object that is invoked at the event-points inside the
     :func:`~graph_tool.search.bfs_search` algorithm. By default, it performs no
@@ -308,10 +278,6 @@ def bfs_search(g, source, visitor=BFSVisitor()):
     .. [bfs-wikipedia] http://en.wikipedia.org/wiki/Breadth-first_search
     """
 
-    visitor = VisitorWrapper(g, visitor,
-                             ["initialize_vertex", "examine_vertex", "finish_vertex"],
-                             ["initialize_vertex"])
-
     try:
         libgraph_tool_search.bfs_search(g._Graph__graph,
                                         int(source), visitor)
@@ -539,10 +505,6 @@ def dfs_search(g, source, visitor=DFSVisitor()):
     .. [dfs-wikipedia] http://en.wikipedia.org/wiki/Depth-first_search
     """
 
-    visitor = VisitorWrapper(g, visitor,
-                             ["initialize_vertex", "discover_vertex", "finish_vertex",
-                              "start_vertex"], ["initialize_vertex"])
-
     try:
         libgraph_tool_search.dfs_search(g._Graph__graph,
                                         int(source), visitor)
@@ -811,10 +773,6 @@ def dijkstra_search(g, source, weight, visitor=DijkstraVisitor(), dist_map=None,
     .. [dijkstra-wikipedia] http://en.wikipedia.org/wiki/Dijkstra's_algorithm
     """
 
-    visitor = VisitorWrapper(g, visitor,
-                             ["initialize_vertex", "examine_vertex", "finish_vertex"],
-                             ["initialize_vertex"])
-
     if visitor is None:
         visitor = DijkstraVisitor()
     if dist_map is None:
@@ -1078,8 +1036,6 @@ def bellman_ford_search(g, source, weight, visitor=BellmanFordVisitor(),
     .. [bellman-ford-wikipedia] http://en.wikipedia.org/wiki/Bellman-Ford_algorithm
     """
 
-    visitor = VisitorWrapper(g, visitor, [], [])
-
     if dist_map is None:
         dist_map = g.new_vertex_property(weight.value_type())
     if pred_map is None:
@@ -1537,10 +1493,6 @@ def astar_search(g, source, weight, visitor=AStarVisitor(),
     .. [astar-wikipedia] http://en.wikipedia.org/wiki/A*_search_algorithm
     """
 
-    visitor = VisitorWrapper(g, visitor,
-                             ["initialize_vertex", "examine_vertex", "finish_vertex"],
-                             ["initialize_vertex"])
-
     if dist_map is None:
         dist_map = g.new_vertex_property(weight.value_type())
     if pred_map is None:
@@ -1572,9 +1524,6 @@ def astar_search(g, source, weight, visitor=AStarVisitor(),
 
     try:
         if not implicit:
-            g._Graph__perms.update({"del_vertex": False, "del_edge": False,
-                                    "add_edge": False})
-
             libgraph_tool_search.astar_search(g._Graph__graph,
                                               int(source), _prop("v", g, dist_map),
                                               _prop("v", g, pred_map),
@@ -1587,19 +1536,13 @@ def astar_search(g, source, weight, visitor=AStarVisitor(),
             elif cost_map.value_type() != dist_map.value_type():
                 raise ValueError("The cost_map value type must be the same as" +
                                  " dist_map.")
-            g._Graph__perms.update({"del_vertex": False})
             libgraph_tool_search.astar_search_implicit\
                 (g._Graph__graph, int(source),
                  _prop("v", g, dist_map), _prop("v", g, pred_map),
                  _prop("v", g, cost_map), _prop("e", g, weight), visitor,
                  compare, combine, zero, infinity, h)
     except StopSearch:
-        g._Graph__perms.update({"del_vertex": True, "del_edge": True,
-                                "add_edge": True})
-    finally:
-        g._Graph__perms.update({"del_vertex": True, "del_edge": True,
-                                "add_edge": True})
-
+        pass
     return dist_map, pred_map