feat(debug): Make ngProbe accept a CSS selector

Closes #970

Author: vicb

lib/application.dart

@@ -126,7 +126,7 @@ class AngularModule extends Module {
  */
 abstract class Application {
   static _find(String selector, [dom.Element defaultElement]) {
-    var element = dom.window.document.querySelector(selector);
+    var element = dom.document.querySelector(selector);
     if (element == null) element = defaultElement;
     if (element == null) {
       throw "Could not find application element '$selector'.";

lib/introspection.dart

@@ -10,34 +10,44 @@ import 'package:angular/core/module_internal.dart';
 import 'package:angular/core_dom/module_internal.dart';
 
 /**
- * Return the closest [ElementProbe] object for a given [Element].
+ * Return the [ElementProbe] object for the closest [Element] in the hierarchy.
+ *
+ * The node parameter could be:
+ * * a [dom.Node],
+ * * a CSS selector for this node.
  *
  * **NOTE:** This global method is here to make it easier to debug Angular
  * application from the browser's REPL, unit or end-to-end tests. The
  * function is not intended to be called from Angular application.
  */
-ElementProbe ngProbe(dom.Node node) {
-  if (node == null) {
-    throw "ngProbe called without node";
+ElementProbe ngProbe(nodeOrSelector) {
+  var errorMsg;
+  var node;
+  if (nodeOrSelector == null) throw "ngProbe called without node";
+  if (nodeOrSelector is String) {
+    var nodes = ngQuery(dom.document, nodeOrSelector);
+    if (nodes.isNotEmpty) node = nodes.first;
+    errorMsg = "Could not find a probe for the selector '$nodeOrSelector' nor its parents";
+  } else {
+    node = nodeOrSelector;
+    errorMsg = "Could not find a probe for the node '$node' nor its parents";
   }
-  var origNode = node;
   while (node != null) {
     var probe = elementExpando[node];
     if (probe != null) return probe;
     node = node.parent;
   }
-  throw "Could not find a probe for [$origNode]";
+  throw errorMsg;
 }
 
-
 /**
  * Return the [Injector] associated with a current [Element].
  *
  * **NOTE**: This global method is here to make it easier to debug Angular
  * application from the browser's REPL, unit or end-to-end tests. The function
  * is not intended to be called from Angular application.
  */
-Injector ngInjector(dom.Node node) => ngProbe(node).injector;
+Injector ngInjector(nodeOrSelector) => ngProbe(nodeOrSelector).injector;
 
 
 /**
@@ -47,7 +57,7 @@ Injector ngInjector(dom.Node node) => ngProbe(node).injector;
  * application from the browser's REPL, unit or end-to-end tests. The function
  * is not intended to be called from Angular application.
  */
-Scope ngScope(dom.Node node) => ngProbe(node).scope;
+Scope ngScope(nodeOrSelector) => ngProbe(nodeOrSelector).scope;
 
 
 List<dom.Element> ngQuery(dom.Node element, String selector,
@@ -70,14 +80,11 @@ List<dom.Element> ngQuery(dom.Node element, String selector,
 }
 
 /**
- * Return a List of directive controllers associated with a current [Element].
+ * Return a List of directives associated with a current [Element].
  *
  * **NOTE**: This global method is here to make it easier to debug Angular
  * application from the browser's REPL, unit or end-to-end tests. The function
  * is not intended to be called from Angular application.
  */
-List<Object> ngDirectives(dom.Node node) {
-  ElementProbe probe = elementExpando[node];
-  return probe == null ? [] : probe.directives;
-}
+List<Object> ngDirectives(nodeOrSelector) => ngProbe(nodeOrSelector).directives;
 

lib/introspection_js.dart

@@ -17,11 +17,14 @@ var elementExpando = new Expando('element');
 
 publishToJavaScript() {
   js.context
-    ..['ngProbe'] = new js.JsFunction.withThis((_, dom.Node node) => _jsProbe(ngProbe(node)))
-    ..['ngInjector'] = new js.JsFunction.withThis((_, dom.Node node) => _jsInjector(ngInjector(node)))
-    ..['ngScope'] = new js.JsFunction.withThis((_, dom.Node node) => _jsScope(ngScope(node), ngProbe(node).injector.get(ScopeStatsConfig)))
+    ..['ngProbe'] = new js.JsFunction.withThis((_, nodeOrSelector) =>
+        _jsProbe(ngProbe(nodeOrSelector)))
+    ..['ngInjector'] = new js.JsFunction.withThis((_, nodeOrSelector) =>
+        _jsInjector(ngInjector(nodeOrSelector)))
+    ..['ngScope'] = new js.JsFunction.withThis((_, nodeOrSelector) =>
+        _jsScope(ngScope(nodeOrSelector), ngProbe(nodeOrSelector).injector.get(ScopeStatsConfig)))
     ..['ngQuery'] = new js.JsFunction.withThis((_, dom.Node node, String selector, [String containsText]) =>
-  new js.JsArray.from(ngQuery(node, selector, containsText)));
+        new js.JsArray.from(ngQuery(node, selector, containsText)));
 }
 
 js.JsObject _jsProbe(ElementProbe probe) {
@@ -34,7 +37,7 @@ js.JsObject _jsProbe(ElementProbe probe) {
 }
 
 js.JsObject _jsInjector(Injector injector) =>
-new js.JsObject.jsify({"get": injector.get})..['_dart_'] = injector;
+    new js.JsObject.jsify({"get": injector.get})..['_dart_'] = injector;
 
 js.JsObject _jsScope(Scope scope, ScopeStatsConfig config) {
   return new js.JsObject.jsify({

test/introspection_spec.dart

@@ -3,6 +3,7 @@ library introspection_spec;
 import '_specs.dart';
 import 'dart:js' as js;
 import 'package:angular/application_factory.dart';
+import 'dart:html';
 
 void main() {
   describe('introspection', () {
@@ -31,6 +32,20 @@ void main() {
       expect(toHtml(ngQuery(div, 'li', 'xxx'))).toEqual('');
     });
 
+    it('should select probe using CSS selector', (TestBed _) {
+      _.compile('<div ng-show="true">WORKS</div>');
+      document.body.append(_.rootElement);
+      var div = new Element.html('<div><p><span></span></p></div>');
+      var span = div.querySelector('span');
+      var shadowRoot = span.createShadowRoot();
+      shadowRoot.innerHtml = '<ul><li>stash</li><li>secret</li><ul>';
+
+      ElementProbe probe = ngProbe('[ng-show]');
+      expect(probe).toBeDefined();
+      expect(probe.injector.get(NgShow) is NgShow).toEqual(true);
+      _.rootElement.remove();
+    });
+
     it('should select elements in the root shadow root', () {
       var div = new Element.html('<div></div>');
       var shadowRoot = div.createShadowRoot();