doc: address how to use TAEF (#7590)

This PR updates the doc in the repo to address how to use TAEF as part
of the development workflow.

Closes #1962

CONTRIBUTING.md

@@ -140,6 +140,13 @@ Once you've discussed your proposed feature/fix/etc. with a team member, and you
 1. Create & push a feature branch
 1. Create a [Draft Pull Request (PR)](https://github.blog/2019-02-14-introducing-draft-pull-requests/)
 1. Work on your changes
+1. Build and see if it works. Consult [How to build OpenConsole](./doc/building.md) if you have problems.
+
+### Testing
+
+Testing is a key component in the development workflow. Both Windows Terminal and Windows Console use TAEF(the Test Authoring and Execution Framework) as the main framework for testing.
+
+If your changes affect existing test cases, or you're working on brand new features and also the accompanying test cases, see [TAEF](./doc/TAEF.md) for more information about how to validate your work locally.
 
 ### Code Review
 

doc/TAEF.md

@@ -1,9 +1,30 @@
-### TAEF ###
+### TAEF Overview ###
+
 TAEF, the Test Authoring and Execution Framework, is used extensively within the Windows organization to test the operating system code in a unified manner for system, driver, and application code. As the console is a Windows OS Component, we strive to continue using the same system such that tests can be ran in a unified manner both externally to Microsoft as well as inside the official OS Build/Test system.
 
-The [official documentation](https://msdn.microsoft.com/en-us/library/windows/hardware/hh439725\(v=vs.85\).aspx) for TAEF describes the basic architecture, usage, and functionality of the test system. It is similar to Visual Studio test, but a bit more comprehensive and flexible.
+The [official documentation](https://docs.microsoft.com/en-us/windows-hardware/drivers/taef/) for TAEF describes the basic architecture, usage, and functionality of the test system. It is similar to Visual Studio test, but a bit more comprehensive and flexible.
 
-For the purposes of the console project, you can run the tests using the *TE.exe* that matches the architecture for which the test was build (x86/x64) in the pattern
+### Writing Tests
+
+You may want to read the section [Authoring Tests in C++](https://docs.microsoft.com/en-us/windows-hardware/drivers/taef/authoring-tests-in-c--) before getting your hands dirty. Note that the quoted header name in `#include "WexTestClass.h"` might be a bit confusing. You are not required to copy TAEF headers into the project folder.
+
+Use the [TAEF Verify Macros for C++](https://docs.microsoft.com/en-us/windows-hardware/drivers/taef/verify) in your test code to perform verifications.
+
+### Running Tests
+
+If you have Visual Studio and related C++ components installed, and you have successfully restored NuGets, you should have the TAEF test runner `te.exe` available locally as part of the `Taef.Redist.Wlk` package.
+
+> Note that you cannot easily run TAEF tests directly through Visual Studio. The `Taef.Redist.Wlk` NuGet package comes with an adapter that will let you browse and execute TAEF tests inside of Visual Studio, but its performance and reliability prevent us from recommending it here.
+
+In a "normal" CMD environment, `te.exe` may not be directly available. Try the following command to set up the development enviroment first:
+
+```shell
+.\tools\razzle.cmd
+```
+
+Then you should be able to use `%TAEF%` as an alias of the actual `te.exe`.
+
+For the purposes of the OpenConsole project, you can run the tests using the `te.exe` that matches the architecture for which the test was built (x86/x64):
 
 	te.exe Console.Unit.Tests.dll
 
@@ -15,6 +36,15 @@ Limiting the tests to be run is also useful with:
 
 Any pattern of class/method names can be specified after the */name:* flag with wildcard patterns.
 
-For any further details on the functionality of the TAEF test runner, *TE.exe*, please see the documentation above or run the embedded help with
+For any further details on the functionality of the TAEF test runner, please see the [Executing Tests](https://docs.microsoft.com/en-us/windows-hardware/drivers/taef/executing-tests) section in the official documentation. Or run the embedded help with
 
 	te.exe /!
+
+If you use PowerShell, try the following command:
+
+```powershell
+Import-Module .\tools\OpenConsole.psm1
+Invoke-OpenConsoleTests
+```
+
+`Invoke-OpenConsoleTests` supports a number of options, which you can enumerate by running `Invoke-OpenConsoleTests -?`.