use apply and call on WebExtension API functions

Question

Created Sep ’20

Replies 3

Boosts 0

Participants 2

Hi,
I am converting a chrome extension to safari web extension.
In my test in Safari 14 beta 4. (14610.1.26), it seems the web extension api can't use the apply or call method.
For example:
In Chrome, we can use

Code Block javascriptchrome.tabs.query.apply(null, [{}, function(tabs){
  console.log(1, tabs);
}]);

But in Safari, this will not work, we can only use

Code Block javascriptbrowser.tabs.query({}, function(tabs){
  console.log(1, tabs)
});

It would be very helpful if in Safari we can use apply and call method for WebExtension APIs

Thank you very much

Answered by Frameworks Engineer in 630955022

Both of these cases are because the API functions require a proper this object when called. This is currently a requirement in Safari and different from Chrome.

For the first case you can do:

Code Block browser.tabs.query.apply(browser.tabs, [{}, function(tabs){
    console.log(1, tabs);
}]);

Or in the second case:

Code Block apiTest(browser.tabs.query.bind(browser.tabs));

Here is some more info on bind() and this object.

Boost

Answer 1

lu.xu OP

Sep ’20

Another interesting finding is, seems we can not pass the API as a parameter

Code Block javascriptfunction apiTest(method){
  method({}, function(result) {
    console.log('Result', result);
  });
}
apiTest(browser.tabs.query);

This works in Chrome, but not working in Safari

0

Answer 2

Frameworks Engineer OP

Apple

Sep ’20

Accepted Answer

Both of these cases are because the API functions require a proper this object when called. This is currently a requirement in Safari and different from Chrome.

For the first case you can do:

Code Block browser.tabs.query.apply(browser.tabs, [{}, function(tabs){
    console.log(1, tabs);
}]);

Or in the second case:

Code Block apiTest(browser.tabs.query.bind(browser.tabs));

Here is some more info on bind() and this object.

0

Answer 3

lu.xu OP

Sep ’20

Thanks timothy, it works!

0