feat(ordering): add sequence flow + association to correct parent

* remove ModelUtil#getSharedParent because we do proper ordering
  via BpmnOrderingProvider now.
* Cherio!

Related to #316

lib/features/modeling/Modeling.js

@@ -47,8 +47,6 @@ Modeling.prototype.updateLabel = function(element, newLabel) {
 };
 
 
-var getSharedParent = require('./ModelingUtil').getSharedParent;
-
 Modeling.prototype.connect = function(source, target, attrs) {
 
   var bpmnRules = this._bpmnRules;
@@ -70,7 +68,7 @@ Modeling.prototype.connect = function(source, target, attrs) {
     }
   }
 
-  return this.createConnection(source, target, attrs, getSharedParent(source, target));
+  return this.createConnection(source, target, attrs, source.parent);
 };
 
 

lib/features/modeling/ModelingUtil.js

@@ -1,7 +1,5 @@
 'use strict';
 
-var find = require('lodash/collection/find');
-
 
 function getParents(element) {
 
@@ -19,16 +17,3 @@ function getParents(element) {
 }
 
 module.exports.getParents = getParents;
-
-
-function getSharedParent(a, b) {
-
-  var parentsA = getParents(a),
-      parentsB = getParents(b);
-
-  return find(parentsA, function(parent) {
-    return parentsB.indexOf(parent) !== -1;
-  });
-}
-
-module.exports.getSharedParent = getSharedParent;

lib/features/modeling/behavior/ReplaceConnectionBehavior.js

@@ -5,8 +5,7 @@ var forEach = require('lodash/collection/forEach'),
 
 var CommandInterceptor = require('diagram-js/lib/command/CommandInterceptor');
 
-var is = require('../../../util/ModelUtil').is,
-    getSharedParent = require('../ModelingUtil').getSharedParent;
+var is = require('../../../util/ModelUtil').is;
 
 function ReplaceConnectionBehavior(eventBus, modeling, bpmnRules) {
 
@@ -73,10 +72,10 @@ function ReplaceConnectionBehavior(eventBus, modeling, bpmnRules) {
     // replace SequenceFlow <> MessageFlow
 
     if (replacementType) {
-      modeling.createConnection(source, target, {
+      modeling.connect(source, target, {
         type: replacementType,
         waypoints: connection.waypoints.slice()
-      }, getSharedParent(source, target));
+      });
     }
   }
 

lib/features/ordering/BpmnOrderingProvider.js

@@ -4,6 +4,7 @@ var inherits = require('inherits');
 
 var OrderingProvider = require('diagram-js/lib/features/ordering/OrderingProvider');
 
+var is = require('../../util/ModelUtil').is;
 
 var findIndex = require('lodash/array/findIndex');
 
@@ -22,8 +23,28 @@ function BpmnOrderingProvider(eventBus) {
 
   var orders = [
     { type: 'label', order: { level: 7 } },
-    { type: 'bpmn:SequenceFlow', order: { level: 5 } },
-    { type: 'bpmn:MessageFlow', order: { level: 6, top: true } },
+    {
+      type: 'bpmn:SequenceFlow',
+      order: {
+        level: 5,
+        containers: [
+          'bpmn:Participant',
+          'bpmn:FlowElementsContainer'
+        ]
+      }
+    },
+    {
+      type: 'bpmn:Association',
+      order: {
+        level: 6,
+        containers: [
+          'bpmn:Participant',
+          'bpmn:FlowElementsContainer',
+          'bpmn:Collaboration'
+        ]
+      }
+    },
+    { type: 'bpmn:MessageFlow', order: { level: 6, containers: [ 'bpmn:Collaboration' ] } },
     { type: 'bpmn:BoundaryEvent', order: { level: 4 } },
     { type: 'bpmn:Participant', order: { level: -2 } },
     { type: 'bpmn:Lane', order: { level: -1 } }
@@ -48,15 +69,41 @@ function BpmnOrderingProvider(eventBus) {
     return order;
   }
 
+  var any = require('lodash/collection/any');
+
+  function isAny(element, types) {
+    return any(types, function(t) {
+      return is(element, t);
+    });
+  }
+
+  function findActualParent(element, newParent, containers) {
+
+    var actualParent = newParent;
+
+    while (actualParent) {
+
+      if (isAny(actualParent, containers)) {
+        break;
+      }
+
+      actualParent = actualParent.parent;
+    }
+
+    if (!actualParent) {
+      throw new Error('no parent for ' + element.id + ' in ' + newParent.id);
+    }
+
+    return actualParent;
+  }
+
   this.getOrdering = function(element, newParent) {
 
     var elementOrder = getOrder(element);
 
 
-    if (elementOrder.top) {
-      while (newParent.parent) {
-        newParent = newParent.parent;
-      }
+    if (elementOrder.containers) {
+      newParent = findActualParent(element, newParent, elementOrder.containers);
     }