diff --git a/src/core/source/utils.js b/src/core/source/utils.js
index 86c2030..16ffcca 100644
--- a/src/core/source/utils.js
+++ b/src/core/source/utils.js
@@ -192,8 +192,18 @@ function translateNode(node){
 //
 
 function wrapSource(source, breakpointAt){
+  function wrapToBlock(node){
+    if (node.parentNode.type != 'BlockStatement' && node.parentNode.type != 'Program')
+    {
+      var tokens = getNodeRangeTokens(node);
+      tokens[0].value = '{\n' + tokens[0].value;
+      tokens[1].value = tokens[1].value + '\n}';
+    }
+  }
+
   var ast = parse(source);
 
+
   if (breakpointAt == 'none')
   {
     traverseAst(ast, function(node){
@@ -230,10 +240,12 @@ function wrapSource(source, breakpointAt){
         {
           var token = getNodeRangeTokens(node)[0];
           var singleArg = node.arguments.length == 1 ? node.arguments[0] : null;
-          var isForCode = '__isFor(' + node.range + ',' + (node.loc.end.line - 1) + ')';
-          var newValue = token.value.replace(/^__enterLine\(\d+\)/, isForCode);
+          var isForCode = 'if(__isFor(' + node.range + ',' + (node.loc.end.line - 1) + '))debugger;\n';
+          var newValue = token.value.replace(/^__enterLine\(\d+\); /, isForCode);
+
+          token.value = newValue != token.value ? newValue : isForCode + token.value;
 
-          token.value = newValue != token.value ? newValue : isForCode + ' || ' + token.value;
+          wrapToBlock(node.parentNode);
 
           if (singleArg &&
               singleArg.type == 'BinaryExpression' &&
diff --git a/src/core/test.js b/src/core/test.js
index b8192f2..245083b 100644
--- a/src/core/test.js
+++ b/src/core/test.js
@@ -218,10 +218,18 @@ var TestCase = AbstractTest.subclass({
       this.testWrappedSources = {};
 
     if (!this.testWrappedSources[breakpointAt])
+    {
+      var sourceMap = '';
+        // '\n//# sourceMappingURL=data:application/json;base64,' +
+        // require('basis.utils.base64').encode('{"version":3,"sources":["' + basis.path.origin + '/foo.js' + '"],"sourcesContent":[' + JSON.stringify(source) + '],' +
+        // '"mappings":"AAAA' + basis.string.repeat(';AACA', source.split('\n').length) +
+        // '"}', true) + '\n';
+
       this.testWrappedSources[breakpointAt] =
         'function(' + sourceUtils.getFunctionInfo(this.data.test).args.concat('assert', '__isFor', '__enterLine', '__exception', '__wrapFunctionExpression', '__actual', '__expected').join(', ') + '){\n' +
           sourceUtils.getWrappedSource(source, breakpointAt) +
-        '\n}';
+        '\n}' + sourceMap;
+    }
 
     return this.testWrappedSources[breakpointAt];
   },
@@ -236,7 +244,7 @@ var TestCase = AbstractTest.subclass({
     AbstractTest.prototype.reset.call(this);
     this.setState(STATE.UNDEFINED);
   },
-  run: function(){
+  run: function(breakAssert){
     // var _warn = basis.dev.warn;
     // var _error = basis.dev.error;
     var warnMessages = [];
@@ -247,6 +255,7 @@ var TestCase = AbstractTest.subclass({
     var timeoutTimer;
     var async = this.data.async ? 1 : 0;
     var isNode = null;
+    var isForNum = 0;
     var sourceCode = this.getSourceCode();
     var beforeAfterInfo = this.getBeforeAfterInfo();
 
@@ -328,6 +337,7 @@ var TestCase = AbstractTest.subclass({
 
             errors.push({
               num: report.testCount,
+              debug: isForNum,
               node: isNode,
               error: error,
               expected: utils.makeStaticCopy(expected),
@@ -364,6 +374,7 @@ var TestCase = AbstractTest.subclass({
         range: [start, end],
         line: line
       };
+      return ++isForNum === breakAssert;
     };
 
     var __enterLine = function(line){
diff --git a/src/reporter/app.js b/src/reporter/app.js
index fe81b6a..f04c54e 100644
--- a/src/reporter/app.js
+++ b/src/reporter/app.js
@@ -44,18 +44,18 @@ toc.addHandler({
 });
 toc.selection.addHandler({
   itemsChanged: function(selection){
-    this.setDelegate(selection.pick());
+    testDetails.setDelegate(selection.pick());
   }
-}, testDetails);
+});
 
 // content section setup
 testDetails.selection.addHandler({
   itemsChanged: function(selection){
     var selected = selection.pick();
     if (selected)
-      this.setDelegate(selected.root);
+      toc.setDelegate(selected.root);
   }
-}, toc);
+});
 
 var view = new Node({
   template: resource('./template/view.tmpl'),
diff --git a/src/reporter/app/check-debugger.js b/src/reporter/app/check-debugger.js
new file mode 100644
index 0000000..775e327
--- /dev/null
+++ b/src/reporter/app/check-debugger.js
@@ -0,0 +1,31 @@
+var Node = require('basis.ui').Node;
+
+var timer;
+var view = new Node({
+  show: new basis.Token(false),
+  template: resource('./template/debugger-open.tmpl'),
+  binding: {
+    show: 'show'
+  }
+});
+
+basis.doc.body.ready(function(body){
+  body.appendChild(view.element);
+});
+
+module.exports = function(){
+  if (timer)
+    timer = clearTimeout(timer);
+
+  var time = Date.now();
+  view.show.set(false);
+  timer = setTimeout(function(){
+    if (Date.now() - time < 200)
+    {
+      view.show.set(true);
+      timer = setTimeout(function(){
+        view.show.set(false);
+      }, 3000);
+    }
+  }, 100);
+};
diff --git a/src/reporter/app/template/debugger-open.css b/src/reporter/app/template/debugger-open.css
new file mode 100644
index 0000000..4449097
--- /dev/null
+++ b/src/reporter/app/template/debugger-open.css
@@ -0,0 +1,17 @@
+.notify
+{
+  position: fixed;
+  top: 45px;
+  right: 5px;
+  padding: 8px;
+  background: rgba(0,0,0,.75);
+  color: white;
+  font-family: Tahoma, serif;
+  opacity: 0;
+  transition: opacity .25s;
+  z-index: 100;
+}
+.notify_show
+{
+  opacity: 1;
+}
diff --git a/src/reporter/app/template/debugger-open.tmpl b/src/reporter/app/template/debugger-open.tmpl
new file mode 100644
index 0000000..bfb87bb
--- /dev/null
+++ b/src/reporter/app/template/debugger-open.tmpl
@@ -0,0 +1,7 @@
+<b:style src="./debugger-open.css"/>
+<b:isolate/>
+<b:define name="show" type="bool"/>
+
+<div class="notify notify_{show}">
+  To see effect, debugger should be opened.
+</div>
diff --git a/src/reporter/app/template/test-source.css b/src/reporter/app/template/test-source.css
index 8fb373c..56adf9d 100644
--- a/src/reporter/app/template/test-source.css
+++ b/src/reporter/app/template/test-source.css
@@ -104,6 +104,24 @@
   margin: 0;
   margin-top: 1px;
   overflow: hidden;
+  cursor: pointer;
+  position: relative;
+}
+.Basis-SyntaxHighlight .error-line-details-item:hover
+{
+  background: #F8F8F8;
+  box-shadow: 0 0 0px 1px white inset;
+}
+.Basis-SyntaxHighlight .error-line-details-item:hover:after
+{
+  content: 'pause before this assert';
+  position: absolute;
+  top: 3px;
+  right: 3px;
+  padding: 2px 6px;
+  background: black;
+  background: rgba(0,0,0,.65);
+  color: white;
 }
 .Basis-SyntaxHighlight .error-line-details-item:first-child
 {
diff --git a/src/reporter/app/template/test.css b/src/reporter/app/template/test.css
index f7ee371..c313ad5 100644
--- a/src/reporter/app/template/test.css
+++ b/src/reporter/app/template/test.css
@@ -60,12 +60,14 @@
 .loc-link
 {
   cursor: pointer;
-  border-bottom: 1px solid black;
-  border-color: rgba(0, 0, 0, .2);
+  /*border-bottom: 1px solid black;
+  border-color: rgba(0, 0, 0, .2);*/
+  background: linear-gradient(to bottom, rgba(128, 128, 128, .25) 1px, transparent 1px) repeat-x 0 1.2em;
 }
 .loc-link:hover
 {
   color: #A00;
-  border-color: #A00;
-  border-color: rgba(160, 0, 0, .2);
+  /*border-color: #A00;
+  border-color: rgba(160, 0, 0, .2);*/
+  background-image: linear-gradient(to bottom, rgba(160, 0, 0, .25) 1px, transparent 1px);
 }
diff --git a/src/reporter/app/test.js b/src/reporter/app/test.js
index 55e62ac..9b46b4c 100644
--- a/src/reporter/app/test.js
+++ b/src/reporter/app/test.js
@@ -9,6 +9,7 @@ var Node = require('basis.ui').Node;
 //
 
 var document = global.document;
+var checkDebugger = require('./check-debugger.js');
 var highlight = require('app.highlight');
 var TestCase = require('core.test').TestCase;
 var strDiff = require('diff');
@@ -43,7 +44,7 @@ var CodeView = Node.subclass({
       getter: function(node){
         return node.getBeforeAfterInfo().afterCount;
       }
-    },    
+    },
     afterCollapsed: 'afterCollapsed',
     hasParent: {
       events: 'ownerChanged',
@@ -60,6 +61,14 @@ var CodeView = Node.subclass({
     },
     toggleAfter: function(){
       this.afterCollapsed.set(!this.afterCollapsed.value);
+    },
+    debug: function(event){
+      var target = event.actionTarget;
+      var debug = Number(target.getAttribute('data-debug'));
+      var test = this.root instanceof TestCase ? this.root : this.data.test;
+
+      checkDebugger();
+      test.run(debug);
     }
   },
 
@@ -157,7 +166,7 @@ var CodeView = Node.subclass({
               }
 
               return (
-                '<div class="error-line-details-item">' +
+                '<div class="error-line-details-item" event-click="debug" data-debug="' + lineError.debug + '">' +
                   '<span class="num">' + (lineError.num + 1) + '</span>' +
                   '<span class="caption">Expected:</span>' +
                   '<span class="expected">' + expected + '</span>' +
@@ -271,6 +280,7 @@ var TestSuiteNode = TestNode.subclass({
 
   template: resource('./template/test-suite.tmpl'),
 
+  sorting: 'root.basisObjectId',
   childClass: TestNode,
   childFactory: function(config){
     if (config.delegate.data.type == 'case')