Add pylint to depot_tools.

third_party/logilab/common/graph.py

+# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
+#
+# This file is part of logilab-common.
+#
+# logilab-common is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation, either version 2.1 of the License, or (at your option) any
+# later version.
+#
+# logilab-common is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Lesser General Public License along
+# with logilab-common.  If not, see <http://www.gnu.org/licenses/>.
+"""Graph manipulation utilities.
+
+(dot generation adapted from pypy/translator/tool/make_dot.py)
+"""
+
+__docformat__ = "restructuredtext en"
+
+__metaclass__ = type
+
+import os.path as osp
+import os
+import sys
+import tempfile
+from logilab.common.compat import str_encode
+
+def escape(value):
+    """Make <value> usable in a dot file."""
+    lines = [line.replace('"', '\\"') for line in value.split('\n')]
+    data = '\\l'.join(lines)
+    return '\\n' + data
+
+def target_info_from_filename(filename):
+    """Transforms /some/path/foo.png into ('/some/path', 'foo.png', 'png')."""
+    basename = osp.basename(filename)
+    storedir = osp.dirname(osp.abspath(filename))
+    target = filename.split('.')[-1]
+    return storedir, basename, target
+
+
+class DotBackend:
+    """Dot File backend."""
+    def __init__(self, graphname, rankdir=None, size=None, ratio=None,
+            charset='utf-8', renderer='dot', additionnal_param={}):
+        self.graphname = graphname
+        self.renderer = renderer
+        self.lines = []
+        self._source = None
+        self.emit("digraph %s {" % normalize_node_id(graphname))
+        if rankdir:
+            self.emit('rankdir=%s' % rankdir)
+        if ratio:
+            self.emit('ratio=%s' % ratio)
+        if size:
+            self.emit('size="%s"' % size)
+        if charset:
+            assert charset.lower() in ('utf-8', 'iso-8859-1', 'latin1'), \
+                   'unsupported charset %s' % charset
+            self.emit('charset="%s"' % charset)
+        for param in additionnal_param.iteritems():
+            self.emit('='.join(param))
+
+    def get_source(self):
+        """returns self._source"""
+        if self._source is None:
+            self.emit("}\n")
+            self._source = '\n'.join(self.lines)
+            del self.lines
+        return self._source
+
+    source = property(get_source)
+
+    def generate(self, outputfile=None, dotfile=None, mapfile=None):
+        """Generates a graph file.
+
+        :param outputfile: filename and path [defaults to graphname.png]
+        :param dotfile: filename and path [defaults to graphname.dot]
+
+        :rtype: str
+        :return: a path to the generated file
+        """
+        import subprocess # introduced in py 2.4
+        name = self.graphname
+        if not dotfile:
+            # if 'outputfile' is a dot file use it as 'dotfile'
+            if outputfile and outputfile.endswith(".dot"):
+                dotfile = outputfile
+            else:
+                dotfile = '%s.dot' % name
+        if outputfile is not None:
+            storedir, basename, target = target_info_from_filename(outputfile)
+            if target != "dot":
+                pdot, dot_sourcepath = tempfile.mkstemp(".dot", name)
+                os.close(pdot)
+            else:
+                dot_sourcepath = osp.join(storedir, dotfile)
+        else:
+            target = 'png'
+            pdot, dot_sourcepath = tempfile.mkstemp(".dot", name)
+            ppng, outputfile = tempfile.mkstemp(".png", name)
+            os.close(pdot)
+            os.close(ppng)
+        pdot = open(dot_sourcepath, 'w')
+        pdot.write(str_encode(self.source, 'utf8'))
+        pdot.close()
+        if target != 'dot':
+            if sys.platform == 'win32':
+                use_shell = True
+            else:
+                use_shell = False
+            if mapfile:
+                subprocess.call([self.renderer,  '-Tcmapx', '-o', mapfile, '-T', target, dot_sourcepath, '-o', outputfile],
+                                shell=use_shell)
+            else:
+                subprocess.call([self.renderer, '-T',  target,
+                                 dot_sourcepath, '-o',  outputfile],
+                                shell=use_shell)
+            os.unlink(dot_sourcepath)
+        return outputfile
+
+    def emit(self, line):
+        """Adds <line> to final output."""
+        self.lines.append(line)
+
+    def emit_edge(self, name1, name2, **props):
+        """emit an edge from <name1> to <name2>.
+        edge properties: see http://www.graphviz.org/doc/info/attrs.html
+        """
+        attrs = ['%s="%s"' % (prop, value) for prop, value in props.items()]
+        n_from, n_to = normalize_node_id(name1), normalize_node_id(name2)
+        self.emit('%s -> %s [%s];' % (n_from, n_to, ", ".join(attrs)) )
+
+    def emit_node(self, name, **props):
+        """emit a node with given properties.
+        node properties: see http://www.graphviz.org/doc/info/attrs.html
+        """
+        attrs = ['%s="%s"' % (prop, value) for prop, value in props.items()]
+        self.emit('%s [%s];' % (normalize_node_id(name), ", ".join(attrs)))
+
+def normalize_node_id(nid):
+    """Returns a suitable DOT node id for `nid`."""
+    return '"%s"' % nid
+
+class GraphGenerator:
+    def __init__(self, backend):
+        # the backend is responsible to output the graph in a particular format
+        self.backend = backend
+
+    # XXX doesn't like space in outpufile / mapfile
+    def generate(self, visitor, propshdlr, outputfile=None, mapfile=None):
+        # the visitor
+        # the property handler is used to get node and edge properties
+        # according to the graph and to the backend
+        self.propshdlr = propshdlr
+        for nodeid, node in visitor.nodes():
+            props = propshdlr.node_properties(node)
+            self.backend.emit_node(nodeid, **props)
+        for subjnode, objnode, edge in visitor.edges():
+            props = propshdlr.edge_properties(edge, subjnode, objnode)
+            self.backend.emit_edge(subjnode, objnode, **props)
+        return self.backend.generate(outputfile=outputfile, mapfile=mapfile)
+
+
+class UnorderableGraph(Exception):
+    pass
+
+def ordered_nodes(graph):
+    """takes a dependency graph dict as arguments and return an ordered tuple of
+    nodes starting with nodes without dependencies and up to the outermost node.
+
+    If there is some cycle in the graph, :exc:`UnorderableGraph` will be raised.
+
+    Also the given graph dict will be emptied.
+    """
+    # check graph consistency
+    cycles = get_cycles(graph)
+    if cycles:
+        cycles = '\n'.join([' -> '.join(cycle) for cycle in cycles])
+        raise UnorderableGraph('cycles in graph: %s' % cycles)
+    vertices = set(graph)
+    to_vertices = set()
+    for edges in graph.values():
+        to_vertices |= set(edges)
+    missing_vertices = to_vertices - vertices
+    if missing_vertices:
+        raise UnorderableGraph('missing vertices: %s' % ', '.join(missing_vertices))
+    # order vertices
+    order = []
+    order_set = set()
+    old_len = None
+    while graph:
+        if old_len == len(graph):
+            raise UnorderableGraph('unknown problem with %s' % graph)
+        old_len = len(graph)
+        deps_ok = []
+        for node, node_deps in graph.items():
+            for dep in node_deps:
+                if dep not in order_set:
+                    break
+            else:
+                deps_ok.append(node)
+        order.append(deps_ok)
+        order_set |= set(deps_ok)
+        for node in deps_ok:
+            del graph[node]
+    result = []
+    for grp in reversed(order):
+        result.extend(sorted(grp))
+    return tuple(result)
+
+
+def get_cycles(graph_dict, vertices=None):
+    '''given a dictionary representing an ordered graph (i.e. key are vertices
+    and values is a list of destination vertices representing edges), return a
+    list of detected cycles
+    '''
+    if not graph_dict:
+        return ()
+    result = []
+    if vertices is None:
+        vertices = graph_dict.keys()
+    for vertice in vertices:
+        _get_cycles(graph_dict, vertice, [], result)
+    return result
+
+def _get_cycles(graph_dict, vertice=None, path=None, result=None):
+    """recursive function doing the real work for get_cycles"""
+    if vertice in path:
+        cycle = [vertice]
+        for node in path[::-1]:
+            if node == vertice:
+                break
+            cycle.insert(0, node)
+        # make a canonical representation
+        start_from = min(cycle)
+        index = cycle.index(start_from)
+        cycle = cycle[index:] + cycle[0:index]
+        # append it to result if not already in
+        if not cycle in result:
+            result.append(cycle)
+        return
+    path.append(vertice)
+    try:
+        for node in graph_dict[vertice]:
+            _get_cycles(graph_dict, node, path, result)
+    except KeyError:
+        pass
+    path.pop()
+
+def has_path(graph_dict, fromnode, tonode, path=None):
+    """generic function taking a simple graph definition as a dictionary, with
+    node has key associated to a list of nodes directly reachable from it.
+
+    Return None if no path exists to go from `fromnode` to `tonode`, else the
+    first path found (as a list including the destination node at last)
+    """
+    if path is None:
+        path = []
+    elif fromnode in path:
+        return None
+    path.append(fromnode)
+    for destnode in graph_dict[fromnode]:
+        if destnode == tonode or has_path(graph_dict, destnode, tonode, path):
+            return path[1:] + [tonode]
+    path.pop()
+    return None
+