Summary

Allow marking a test or test class to be ignored unless it is explicitly selected for running, i.e. such test(s) won't be executed when using Run All Tests but will execute when selected for individual run.
Similar to NUnit's [Explicit] attribute: https://docs.nunit.org/articles/nunit/writing-tests/attributes/explicit.html

Background and Motivation

Some tests are meant only to be used by developers on development box to help with debugging or other code simulations.
Currently, we mark these as [Ignored] and enable them only as needed. Unfortunately, this leads to many accidental situations where the test is left un-ignored and committed to the repository.

Proposed Feature

Adding an [Explicit] attribute known from other test frameworks might be a good fit.

• Add Explicit property to [Fact] and friends xunit/xunit#2518
• https://docs.nunit.org/articles/nunit/writing-tests/attributes/explicit.html