fosite.Arguments: Nano optimization of .Exact()

[redbaron]

Previously Arguments.Exact had vague semantic where
it coudln't distinguish between value with a space and multiple
values. Split it into 2 functions with clear semantic.

Old .Exact() remains for compatibility and marked as deprecated

[CLAassistant]

All committers have signed the CLA.

[aeneasr]

These are functionally different because before it worked for len > 1 and now it doesn’t.

[redbaron]

These are functionally different because before it worked for len > 1 and now it doesn’t.

for len>1 before and after it returns false, as it should, no?

[redbaron]

Only case I can see them being different is that previously .Exact() incorrectly returned true for following case:

        var v Arguments = []string{"A", "B"}
	v.Exact("A B") 

do I miss something?

[aeneasr]

        var v Arguments = []string{"A", "B"}
	v.Exact("A B") 

that is the use case I was thinking about. While it does not appear to be used like that anywhere in fosite, it was originally implemented that way because we might have arguments where order matters / must be preserved. I'm not sure if we import this code somewhere else that depends on this behavior, thus I am hesitant to merge it.

[redbaron]

we might have arguments where order matters

This should be covered by func (r Arguments) ExactSlice(names []string) bool

Using .Exact(strings.Join(names," ")) for this purpose is clear misuse

[aeneasr]

That might be, but as I explained we have other code that (might) depend on this behavior and even if you have a better naming for it, it doesn't change that fact! Breaking the functionality in such a way without e.g. renaming the function as well is not something that can be merged.

If you want, you can introduce a new function ExactOne(name string) and ExactSlice and leave the existing one untouched, updating all the code where currently Exact is used and mark Exact as deprecated using godoc.

[redbaron]

Added ExactOne and MatchesExact, also added tests for discussed edge cases

[aeneasr]

Awesome, thank you!