| Index: test/browser/_utils.js | 
| =================================================================== | 
| --- a/test/browser/_utils.js | 
| +++ b/test/browser/_utils.js | 
| @@ -21,8 +21,34 @@ | 
| { | 
| return new Promise(resolve => | 
| { | 
| setTimeout(resolve, delay); | 
| }); | 
| } | 
| exports.timeout = timeout; | 
| + | 
| +function expectHidden(test, element, id) | 
| +{ | 
| + let withId = ""; | 
| + if (typeof id != "undefined") | 
| + withId = ` with ID '${id}'`; | 
| + | 
| + test.equal( | 
| + window.getComputedStyle(element).display, "none", | 
| + `The element${withId}'s display property should be set to 'none'`); | 
| +} | 
| + | 
| +exports.expectHidden = expectHidden; | 
| + | 
| +function expectVisible(test, element, id) | 
| +{ | 
| + let withId = ""; | 
| + if (typeof id != "undefined") | 
| + withId = ` with ID '${id}'`; | 
| + | 
| + test.notEqual( | 
| + window.getComputedStyle(element).display, "none", | 
| + `The element${withId}'s display property should not be set to 'none'`); | 
| +} | 
| + | 
| +exports.expectVisible = expectVisible; |