Add a test for the even handler leaking fix addressed in #10626https://github.com/PowerShell/PowerShell/pull/10626
The test is added to verify that PowerShell unregister the 'AppDomain.ProcessExit' event handler when a Runspace closes.
This PR does 4 things:
* Adds a new cmdlet `New-PSBreakpoint` which creates new `Breakpoint` objects and writes them to the pipeline
* Adds a `-Breakpoint` parameter to `Debug-Runspace` which will receive `Breakpoint` objects
* Makes the constructors for `*Breakpoint` public for use with the API
* Makes `Debugger.GetBreakpoint(string id)` and `Debugger.GetBreakpoints()` public since `SetBreakpoints` is public
Note: `New-PSBreakpoint` and `Set-PSBreakpoint` (which already exists) are similar... but `Set-PSBreakpoint` also sets the breakpoints in the _current_ runspace. This is not ideal if we want to set breakpoints in a _different runspace than the current one_.
## PR Context
The "Attach to process" debugging experience in the PowerShell extension for VSCode is _ok_ but it's not great.
The reason it's not great is due to the `BreakAll` feature of PowerShell debugging which, when you run `Debug-Runspace`, will break at the first piece of code that gets run. This is not ideal when you "Attach to process" _and then_ run your code in the other runspace.
Today, the experience drops you in `PSReadLine`'s psm1 if PSRL is available or in the vscode PowerShell helper psm1.
It's unexpected for the user and not ideal.
This PR will allow the extension to pass in the breakpoints that need to be set initially with `BreakAll` turned off for none of this silly behavior.
### Silly behavior example
If you want a repro, try this:
PowerShell instance 1:
```
Enter-PSHostProcess -Id $otherprocesspid
Debug-Runspace 1
```
PowerShell instance 2:
```
./runfoo.ps1
```
Note that you end up NOT `runfoo.ps1`
By not doing excessive amounts of extra work, formatting can be sped up quite significantly (about 8x faster).
The main change comes from adding new, more efficient, primitive to query an object for the existence of an instance member.
The formatting system has been checking for if an object has properties other than some decorated properties added by PS remoting, and it doesn't this by retrieving all properties which results in heavy allocations and wasted cycles.
By adding `GetFirstOrDefault` to `PSObject` and similar primitives to the underlying Adapters, we are able to return early, without having to get all properties back.
We have the public API `JsonObject.ConvertFromJson` to convert from JSON string in the PowerShell context. It would be good to have a public API for conversion to JSON. This PR refactors the `ConvertTo-Json` cmdlet to move the core implementation to `JsonObject.ConvertToJson`, and make `ConvertTo-Json` call that public method.
This would help the Azure Function PowerShell worker. Currently, we depends on [calling the cmdlet](729710d259/src/PowerShell/PowerShellManager.cs (L198-L205)) to convert object to JSON which is expensive. Once we have the public method `JsonObject.ConvertToJson` exposed, we can call the API directly to avoid a command invocation.
## Motivation
I have a PR where there are many new xUnit tests.
It would also be useful to create new xUnit tests for public APIs.
The number of xUnit tests will increase and their ordering is required.
## PR Summary
- Move C# xUnit tests in new folder. This allows to put new xUnit tests in directory structure in accordance with directory structure where cs files are.
- Use an xUnit TestCaseOrderer attribute to sequentially process tests for `powershell.config.json`.
- Update README.md
- A race condition was fixed which allowed to run all XUnit tests in single batch job.
