Decorator for computed test cases

[Nysosis]

Hi,

Recently came across the desired to be able to specify multiple test cases programmatically (i.e. I had a matrix of combinations I wanted to feed through).

The current @TestCase decorator works great, but AFAIK there's no way to easily specify multiple in that way (there could be, my knowledge of how decorators works is limited).

So what I did was to create a local @TestCases decorator, which was inspired heavily by the @TestCase decorator - except it took an any[][] instead of any[], which allowed me to add multiple items to the TEST_CASES metadata at once.

This allowed me to do something like:

const cases = Array.from(Array(10)).map((_, i) => [i, i * 2])

// ...

@TestCase(...cases)
public FirstIsSecondTimeTwo(first: number, second: number) {
    Expect(second).toBe(first * 2)
}

Obviously a contrived example, but I've found similar functionality very helpful in other unit testing frameworks.

If there's a way of doing it already (native TS/JS or through the library) then point me how and we can close this issue down, otherwise I can either submit a pull request with the decorator I've done and/or we can discuss the interface for specifying computed test cases

[jamesadarich]

Nice idea @Nysosis,

Might be nice to wrap this up as a decorator that takes a generator specifically for this. What do you think?

[Nysosis]

Yup, I did consider making it use a generator at the time. Built it taking an array for simplicity sake just to get it done quick. I'll take a look at re-impl with a generator and submit a PR for it

…

On 30 July 2017 at 00:08, James Richford ***@***.***> wrote: Nice idea @Nysosis <https://github.com/nysosis>, Might be nice to wrap this up as a decorator that takes a generator specifically for this. What do you think? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#413 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFOQHjJV9LxzX9b8Vwsjs7GI9d4go_juks5sS7tygaJpZM4OlSfu> .

[jamesadarich]

I guess if we make it a separate decorator e.g. TestCasesFor or something along those lines there's no reason it couldn't take both? So you can work with whatever suits the situation?

[Nysosis]

Well taking a quick look, I can make it work both ways, generators or explicit array, for the one function easily enough, with a signature of `export function TestCases(caseArguments: IterableIterator<any> | any[][]) { ... }`. Though can't use the spread operator on on the `any[][]` argument to make that mode a bit nice to work with (by saving you typing `[` and `]`)

…

On 30 July 2017 at 09:24, James Richford ***@***.***> wrote: I guess if we make it a separate decorator e.g. TestCasesFor or something along those lines there's no reason it couldn't take both? So you can work with whatever suits the situation? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#413 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFOQHkK2hGkY_zpY6uXdmwzTTyIS_Esrks5sTD3SgaJpZM4OlSfu> .

[jamesadarich]

Closed by #414