Improve error message when "No valid constructors"

[fagossa]

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Fixes

Fixes #8474.

Purpose

This improves the error message when a Module that matches the constructor parameters specified could not be found.

Thanks a lot for your time!

[mkurz]

A more descriptive commit message would be nice 😉

[fagossa]

@mkurz I improved the commit message with a little more detail

[octonato]

@fagossa, the commit message is still "Fix #8474". You only changed the title of the PR.

Can you edit the message and do a push-forced? Tanks.

[fagossa]

@renatocaval Actually I included more detail several lines bellow. I've ammended it so that the whole thing is visible in only one line:

Fix #8474. Improve error message when "No valid constructors"

Is that ok? Thanks for your time

[octonato]

Yep, that's perfect.

Thanks @fagossa

[octonato]

I think you got it the other way around.

If we throw such an exception to the users, we are just telling them which constructors we have found on the module they registered.

The actual suggestion was to inform the users that the module has the wrong constructor signature and therefore they need to adapt.

See @kubukoz comment here:
#8474 (comment)

And @gmethvin comment here:
#8474 (comment)

We should list the valid constructors, not those the user has defined.

[octonato]

I did a quick test and this is what I got:

class OnlyConfigModule(val config: Config) extends AbstractModule {
  override def configure(): Unit = ()
}

val env = Environment.simple()
val conf = Configuration(
  "play.modules.enabled" -> Seq(
    classOf[OnlyConfigModule].getName
  )
)

val located: Seq[Any] = Modules.locate(env, conf)

and it throws..

play.api.PlayException: No valid public constructors for play.api.inject.OnlyConfigModule. 
Expected one of: (com.typesafe.config.Config)

As a user, I would think: that's exactly the constructor that I defined, why it saying that it is expecting this constructor and still not using it.

[fagossa]

:O You are right
I'll take a look at it

[cchantep]

@fagossa any chance to finalize it?

[mkurz]

This got fixed in #10150