fix(dateparser): Throw on invalid date format string.

[stevecavanagh]

This PR replaces #3544. The dateParser will throw an exception for an invalid format string as suggested.

[dmitriz]

Two tests with the same name?

[wesleycho]

There is the question whether it is desirable to throw - Angular has a philosophy of allowing some failures to be silent, such as an Angular expression that fails to execute since the function is undefined.

Thoughts?

[nbering]

As a consumer of angular libraries, I have found that I expect my invalid input to fail silently, and if something is not behaving as expected I watch my own code.

I expect warnings if I'm using something that is deprecated, errors if something fails catastrophically in the architecture of my app, and that's about it.

If user input is invalid, I think that should fail silently unless the developer has set up form validation.

[realityking]

Since the format string will be set most of the time by the developer, I think a fatal error is appropriate. If this turns out to be a problem for someone, a configuration option could be added.

Angular's silence on errors is sometimes a real brain teaser, it'd be good not to take this further.

[stevecavanagh]

I will clean up the formatting in my PR and resubmit in the next day or so.

---- Rouven Weßling wrote ----

Since the format string will be set most of the time by the developer, I think a fatal error is appropriate. If this turns out to be a problem for someone, a configuration option could be added.

Angular's silence on errors is sometimes a real brain teaser, it'd be good not to take this further.

—
Reply to this email directly or view it on GitHub.

[stevecavanagh]

Please close in favor of #3690.

[rvanbaalen]

As requested.

[stevecavanagh]

Please consider #3691 as a replacement for this PR.