clear output in-between test runs

IPython/html/tests/casperjs/test_cases/isolated_svg.js

@@ -1,94 +1,97 b''
 //
 // Test display isolation
 // An object whose metadata contains an "isolated" tag must be isolated
 // from the rest of the document. In the case of inline SVGs, this means
 // that multiple SVGs have different scopes. This test checks that there
 // are no CSS leaks between two isolated SVGs.
 //
 
 casper.notebook_test(function () {
     this.evaluate(function () {
         var cell = IPython.notebook.get_cell(0);
         cell.set_text( "from IPython.core.display import SVG, display_svg\n"
                      + "s1 = '''<svg width='1cm' height='1cm' viewBox='0 0 1000 500'>"
                      + "<defs><style>rect {fill:red;}; </style></defs>"
                      + "<rect id='r1' x='200' y='100' width='600' height='300' /></svg>"
                      + "'''\n"
                      + "s2 = '''<svg width='1cm' height='1cm' viewBox='0 0 1000 500'>"
                      + "<rect id='r2' x='200' y='100' width='600' height='300' /></svg>"
                      + "'''\n"
                      + "display_svg(SVG(s1), metadata=dict(isolated=True))\n"
                      + "display_svg(SVG(s2), metadata=dict(isolated=True))\n"
             );
         cell.execute();
         console.log("hello" );
     });
 
     this.then(function() {
         var fname=this.test.currentTestFile.split('/').pop().toLowerCase();
         this.echo(fname)
         this.echo(this.currentUrl)
         this.evaluate(function (n) {
             IPython.notebook.rename(n);
             console.write("hello" + n);
             IPython.notebook.save_notebook();
         }, {n : fname});
         this.echo(this.currentUrl)
     });
 
     this.then(function() {
     
         url = this.evaluate(function() {
             IPython.notebook.rename("foo");
             //$("span#notebook_name")[0].click();
             //$("input")[0].value = "please-work";
             //$(".btn-primary")[0].click();
             return document.location.href;
         })
         this.echo("renamed" + url);
         this.echo(this.currentUrl);
     });
 
     this.wait_for_output(0);
 
     this.then(function () {
         var colors = this.evaluate(function () {
             var colors = [];
             var ifr = __utils__.findAll("iframe");
             var svg1 = ifr[0].contentWindow.document.getElementById('r1');
             colors[0] = window.getComputedStyle(svg1)["fill"];
             var svg2 = ifr[1].contentWindow.document.getElementById('r2');
             colors[1] = window.getComputedStyle(svg2)["fill"];
             return colors;
         });
 
         this.test.assertEquals(colors[0], '#ff0000', 'First svg should be red');
         this.test.assertEquals(colors[1], '#000000', 'Second svg should be black');
     });
 
     // now ensure that we can pass the same metadata dict to plain old display()
     this.thenEvaluate(function () {
         var cell = IPython.notebook.get_cell(0);
+        cell.clear_output();
         cell.set_text( "from IPython.display import display\n"
                      + "display(SVG(s1), metadata=dict(isolated=True))\n"
                      + "display(SVG(s2), metadata=dict(isolated=True))\n"
             );
         cell.execute();
     });
-   
+
+    this.wait_for_output(0);
+
     // same test as original
     this.then(function () {
         var colors = this.evaluate(function () {
             var colors = [];
             var ifr = __utils__.findAll("iframe");
             var svg1 = ifr[0].contentWindow.document.getElementById('r1');
             colors[0] = window.getComputedStyle(svg1)["fill"];
             var svg2 = ifr[1].contentWindow.document.getElementById('r2');
             colors[1] = window.getComputedStyle(svg2)["fill"];
             return colors;
         });
 
         this.test.assertEquals(colors[0], '#ff0000', 'First svg should be red');
         this.test.assertEquals(colors[1], '#000000', 'Second svg should be black');
     });
 });