Re: Please aim to add informative messages to your exceptions
On Sat, Sep 14, 2019 at 6:50 AM Boris Zbarsky wrote: > That means not using the following when throwing nsresults/DOMExceptions: > >ErrorResult::Throw(nsresult) >ErrorResult::operator=(nsresult) > > and instead using: > >ErrorResult::ThrowDOMException(nsresult, const nsACString&) > > which allows passing a message string that explains why the exception is > being thrown. One word of caution here. Please be careful putting variable data in these messages (e.g., data that varies based on state) as that might end up exposing more information to the site than we are comfortable with. Both from a compatibility/refactoring hazard as well as end user privacy. ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: Please aim to add informative messages to your exceptions
Very good news! Does this have any impact on SpiderMonkey error handling? Cheers, David On 14/09/2019 06:47, Boris Zbarsky wrote: > Hello, > > ErrorResult has two kinds of exception-throwing APIs on it: the older > ones that don't allow specifying a custom message string, and newer ones > that do. People should use the newer ones where possible. > > That means not using the following when throwing nsresults/DOMExceptions: > > ErrorResult::Throw(nsresult) > ErrorResult::operator=(nsresult) > > and instead using: > > ErrorResult::ThrowDOMException(nsresult, const nsACString&) > > which allows passing a message string that explains why the exception is > being thrown. Web developers will thank you and not post tweets like > https://twitter.com/sebmck/status/1155709250225573889 > > When throwing TypeError or RangeError, ThrowTypeError/ThrowRangeError > already require a message string, though I am making some changes in > https://phabricator.services.mozilla.com/D45932 to make it a bit simpler > to pass in custom message strings there. > > Thank you all for making web developers' lives better, > Boris > > P.S. We currently have a _lot_ of uses of the > no-informative-error-message APIs. Some of these might be things we > don't really expect web pages to hit (e.g. exceptions when in the wrong > type of global). But generally speaking all ~560 uses of > operator=(nsresult) are code smells, as are the ~1000 uses of > Throw(NS_ERROR_DOM_*). > ___ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Please aim to add informative messages to your exceptions
Hello, ErrorResult has two kinds of exception-throwing APIs on it: the older ones that don't allow specifying a custom message string, and newer ones that do. People should use the newer ones where possible. That means not using the following when throwing nsresults/DOMExceptions: ErrorResult::Throw(nsresult) ErrorResult::operator=(nsresult) and instead using: ErrorResult::ThrowDOMException(nsresult, const nsACString&) which allows passing a message string that explains why the exception is being thrown. Web developers will thank you and not post tweets like https://twitter.com/sebmck/status/1155709250225573889 When throwing TypeError or RangeError, ThrowTypeError/ThrowRangeError already require a message string, though I am making some changes in https://phabricator.services.mozilla.com/D45932 to make it a bit simpler to pass in custom message strings there. Thank you all for making web developers' lives better, Boris P.S. We currently have a _lot_ of uses of the no-informative-error-message APIs. Some of these might be things we don't really expect web pages to hit (e.g. exceptions when in the wrong type of global). But generally speaking all ~560 uses of operator=(nsresult) are code smells, as are the ~1000 uses of Throw(NS_ERROR_DOM_*). ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
