[Feature] Remove System.out or System.err and use Logger for everything

[lucianoRM]

Hello!

We are using TestNG as a framework for executing E2E tests as a service. Everything works great but I have noticed that the code has multiple places where instead of a Logger, System.out and System.err are used to print information to the screen.

For example: org.testng.internal.Version#displayBanner

It would be really cool if every console output came from a Logger like you are using in other places. This way, we can add extra information to the log line via configuration (requestId for example).
Otherwise, it's really hard for us to find important information in our logs. For example, some failure stack traces are printed this way and are imposible to find.

[krmahadevan]

@lucianoRM what version are you working with? I believe TestNG 7.7.1 uses an slf4j api for its logging needs.

[lucianoRM]

We are using version 7.6.1 but I can still see those System.out in the master branch

For example: https://github.com/cbeust/testng/blob/2e0c8bd9d93dc48fba799e87083cea6cb63978f4/testng-core/src/main/java/org/testng/TestNG.java#L314

[krmahadevan]

@lucianoRM would you be willing to help raise a PR to fix it? We will be more than glad to help you get it merged

[lucianoRM]

Yeah! I could try to. I don't know if I have the time right now though. If I find a slot, I'll send the PR