diff -r 058bb3dc685f -r 0b59724cb3f2 cubicweb/web/views/ibreadcrumbs.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cubicweb/web/views/ibreadcrumbs.py	Sat Jan 16 13:48:51 2016 +0100
@@ -0,0 +1,203 @@
+# copyright 2003-2014 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
+#
+# This file is part of CubicWeb.
+#
+# CubicWeb 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.
+#
+# CubicWeb 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 CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
+"""breadcrumbs components definition for CubicWeb web client"""
+
+__docformat__ = "restructuredtext en"
+from cubicweb import _
+
+from warnings import warn
+
+from six import text_type
+
+from logilab.mtconverter import xml_escape
+
+from cubicweb import tags, uilib
+from cubicweb.entity import Entity
+from cubicweb.predicates import (is_instance, one_line_rset, adaptable,
+                                one_etype_rset, multi_lines_rset, any_rset,
+                                match_form_params)
+from cubicweb.view import EntityView, EntityAdapter
+from cubicweb.web.views import basecomponents
+# don't use AnyEntity since this may cause bug with isinstance() due to reloading
+
+
+
+class IBreadCrumbsAdapter(EntityAdapter):
+    """adapters for entities which can be"located" on some path to display in
+    the web ui
+    """
+    __regid__ = 'IBreadCrumbs'
+    __select__ = is_instance('Any', accept_none=False)
+
+    def parent_entity(self):
+        itree = self.entity.cw_adapt_to('ITree')
+        if itree is not None:
+            return itree.parent()
+        return None
+
+    def breadcrumbs(self, view=None, recurs=None):
+        """return a list containing some:
+
+        * tuple (url, label)
+        * entity
+        * simple label string
+
+        defining path from a root to the current view
+
+        the main view is given as argument so breadcrumbs may vary according to
+        displayed view (may be None). When recursing on a parent entity, the
+        `recurs` argument should be a set of already traversed nodes (infinite
+        loop safety belt).
+        """
+        parent = self.parent_entity()
+        if parent is not None:
+            if recurs:
+                _recurs = recurs
+            else:
+                _recurs = set()
+            if _recurs and parent.eid in _recurs:
+                self.error('cycle in breadcrumbs for entity %s' % self.entity)
+                return []
+            _recurs.add(parent.eid)
+            adapter = parent.cw_adapt_to('IBreadCrumbs')
+            path = adapter.breadcrumbs(view, _recurs) + [self.entity]
+        else:
+            path = [self.entity]
+        if not recurs:
+            if view is None:
+                if 'vtitle' in self._cw.form:
+                    # embeding for instance
+                    path.append( self._cw.form['vtitle'] )
+            elif view.__regid__ != 'primary' and hasattr(view, 'title'):
+                path.append( self._cw._(view.title) )
+        return path
+
+
+class BreadCrumbEntityVComponent(basecomponents.HeaderComponent):
+    __regid__ = 'breadcrumbs'
+    __select__ = (basecomponents.HeaderComponent.__select__
+                  & one_line_rset() & adaptable('IBreadCrumbs'))
+    order = basecomponents.ApplicationName.order + 1
+    context = basecomponents.ApplicationName.context
+    separator = u'&#160;&gt;&#160;'
+    link_template = u'<a href="%s">%s</a>'
+    first_separator = True
+
+    # XXX support kwargs for compat with other components which gets the view as
+    # argument
+    def render(self, w, **kwargs):
+        try:
+            entity = self.cw_extra_kwargs['entity']
+        except KeyError:
+            entity = self.cw_rset.get_entity(0, 0)
+        adapter = entity.cw_adapt_to('IBreadCrumbs')
+        view = self.cw_extra_kwargs.get('view')
+        path = adapter.breadcrumbs(view)
+        if path:
+            self.open_breadcrumbs(w)
+            self.render_breadcrumbs(w, entity, path)
+            self.close_breadcrumbs(w)
+
+    def open_breadcrumbs(self, w):
+        w(u'<span id="breadcrumbs" class="pathbar">')
+        if self.first_separator:
+            w(self.separator)
+
+    def close_breadcrumbs(self, w):
+        w(u'</span>')
+
+    def render_breadcrumbs(self, w, contextentity, path):
+        root = path.pop(0)
+        if isinstance(root, Entity):
+            w(self.link_template % (self._cw.build_url(root.__regid__),
+                                         root.dc_type('plural')))
+            w(self.separator)
+        self.wpath_part(w, root, contextentity, not path)
+        for i, parent in enumerate(path):
+            w(self.separator)
+            w(u"\n")
+            self.wpath_part(w, parent, contextentity, i == len(path) - 1)
+
+    def wpath_part(self, w, part, contextentity, last=False): # XXX deprecates last argument?
+        if isinstance(part, Entity):
+            w(part.view('breadcrumbs'))
+        elif isinstance(part, tuple):
+            url, title = part
+            textsize = self._cw.property_value('navigation.short-line-size')
+            w(self.link_template % (
+                xml_escape(url), xml_escape(uilib.cut(title, textsize))))
+        else:
+            textsize = self._cw.property_value('navigation.short-line-size')
+            w(xml_escape(uilib.cut(text_type(part), textsize)))
+
+
+class BreadCrumbETypeVComponent(BreadCrumbEntityVComponent):
+    __select__ = (basecomponents.HeaderComponent.__select__
+                  & multi_lines_rset() & one_etype_rset()
+                  & adaptable('IBreadCrumbs'))
+
+    def render_breadcrumbs(self, w, contextentity, path):
+        # XXX hack: only display etype name or first non entity path part
+        root = path.pop(0)
+        if isinstance(root, Entity):
+            w(u'<a href="%s">%s</a>' % (self._cw.build_url(root.__regid__),
+                                        root.dc_type('plural')))
+        else:
+            self.wpath_part(w, root, contextentity, not path)
+
+
+class BreadCrumbAnyRSetVComponent(BreadCrumbEntityVComponent):
+    __select__ = basecomponents.HeaderComponent.__select__ & any_rset()
+
+    # XXX support kwargs for compat with other components which gets the view as
+    # argument
+    def render(self, w, **kwargs):
+        self.open_breadcrumbs(w)
+        w(self._cw._('search'))
+        self.close_breadcrumbs(w)
+
+
+class BreadCrumbLinkToVComponent(BreadCrumbEntityVComponent):
+    __select__ = basecomponents.HeaderComponent.__select__ & match_form_params('__linkto')
+
+    def render(self, w, **kwargs):
+        eid = self._cw.list_form_param('__linkto')[0].split(':')[1]
+        entity = self._cw.entity_from_eid(eid)
+        ecmp = self._cw.vreg[self.__registry__].select(
+            self.__regid__, self._cw, entity=entity, **kwargs)
+        ecmp.render(w, **kwargs)
+
+
+class BreadCrumbView(EntityView):
+    __regid__ = 'breadcrumbs'
+
+    def cell_call(self, row, col, **kwargs):
+        entity = self.cw_rset.get_entity(row, col)
+        desc = uilib.cut(entity.dc_description(), 50)
+        # NOTE remember camember: tags.a autoescapes
+        self.w(tags.a(entity.view('breadcrumbtext'),
+                      href=entity.absolute_url(), title=desc))
+
+
+class BreadCrumbTextView(EntityView):
+    __regid__ = 'breadcrumbtext'
+
+    def cell_call(self, row, col, **kwargs):
+        entity = self.cw_rset.get_entity(row, col)
+        textsize = self._cw.property_value('navigation.short-line-size')
+        self.w(uilib.cut(entity.dc_title(), textsize))