chore(draw/BpmnRenderer): exposed _drawPath helper

This allows extensions to reuse the internal drawPath utility.

Cf. #722 for context.

lib/draw/BpmnRenderer.js

@@ -1755,6 +1755,11 @@ function BpmnRenderer(eventBus, styles, pathMap, canvas, priority) {
       strokeWidth: 2
     });
   }
+
+
+  // extension API, use at your own risk
+  this._drawPath = drawPath;
+
 }
 
 

test/spec/draw/BpmnRendererSpec.js

@@ -222,7 +222,7 @@ describe('draw - bpmn renderer', function() {
 
 
   it('should add random ID suffix to marker ID', function(done) {
-    
+
     var xml = require('../../fixtures/bpmn/simple.bpmn');
     bootstrapViewer(xml)(function(err) {
 
@@ -331,4 +331,26 @@ describe('draw - bpmn renderer', function() {
 
   });
 
+
+  describe('extension API', function() {
+
+    var diagramXML = require('../../fixtures/bpmn/simple.bpmn');
+
+    beforeEach(bootstrapModeler(diagramXML, {
+      modules: [
+        coreModule,
+        rendererModule
+      ]
+    }));
+
+
+    it('should expose helpers', inject(function(bpmnRenderer) {
+
+      // then
+      expect(bpmnRenderer._drawPath).to.be.a('function');
+
+    }));
+
+  });
+
 });