## PR type:
What kind of change does this PR introduce?
<!-- Please uncomment one or more that apply to this PR. -->
- Performance improvement
<!-- - Bugfix -->
<!-- - Feature -->
<!-- - Code style update (formatting) -->
<!-- - Refactoring (no functional changes, no api changes) -->
<!-- - Build or CI related changes -->
<!-- - Documentation content changes -->
<!-- - Sample app changes -->
<!-- - Other... Please describe: -->
## What is the current behavior?
<!-- Please describe the current behavior that you are modifying, or link to a relevant issue. -->
The `MemoryStream` type wraps a `Memory<byte>` instance, so every time a read/write operation needs to be performed, it will need to use `Memory<T>.Span`, which is relatively expensive to invoke, as it needs to handle multiple possible sources of data. We can use generic types and the value delegate trick (constrained generic struct + interface) to optimize this away.
## What is the new behavior?
<!-- Describe how was this issue resolved or changed? -->
We now use a `MemoryStream<TSource>` type (which is internal anyway) and have a bunch of `IMemorySource` types specifically supporting `byte[]` and `MemoryManager<byte>` sources with additional optimizations wherever possible. Also, just using this already removes all the overhead of dynamically creating a `Span<T>` from the wrapped `Memory<T>` instance.
Here's a benchmark I put together to show the before/after:
The benchmark consists of writing 1024 times a 1024 bytes buffer to a target `Stream` instance.
The new `MemoryStream<TSource>` version is almost 25% faster just thanks to this change 🚀
## PR Checklist
Please check if your PR fulfills the following requirements:
- [X] Tested code with current [supported SDKs](../readme.md#supported)
- [ ] ~~Pull Request has been submitted to the documentation repository [instructions](..\contributing.md#docs).~~
- [ ] ~~Sample in sample app has been added / updated (for bug fixes / features)~~
- [ ] ~~Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/windows-toolkit/WindowsCommunityToolkit-design-assets)~~
- [X] Tests for the changes have been added (for bug fixes / features) (if applicable)
- [X] Header has been added to all new source files (run *build/UpdateHeaders.bat*)
- [X] Contains **NO** breaking changes
## Overview
Some `Guard` APIs were incorrectly using the wrong capitalization for the `WhiteSpace` part, not following the same structure of the actual APIs in the BCL (eg. `string.IsNullOrWhiteSpace`). This PR deprecates them and adds new APIs with the right name.
...I'm sorry 😅
<!-- Add a brief overview here of the feature/bug & fix. -->
## PR Type
What kind of change does this PR introduce?
<!-- Please uncomment one or more that apply to this PR. -->
- API rename
- API deprecation
## PR Checklist
Please check if your PR fulfills the following requirements:
- [X] Tested code with current [supported SDKs](../readme.md#supported)
- [ ] ~~Pull Request has been submitted to the documentation repository [instructions](..\contributing.md#docs). Link: <!-- docs PR link -->~~
- [ ] ~~Sample in sample app has been added / updated (for bug fixes / features)~~
- [ ] ~~Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/windows-toolkit/WindowsCommunityToolkit-design-assets)~~
- [ ] ~~Tests for the changes have been added (for bug fixes / features) (if applicable)~~
- [ ] ~~Header has been added to all new source files (run *build/UpdateHeaders.bat*)~~
- [X] Contains **NO** breaking changes
## Follow up for #3131
<!-- Add a brief overview here of the feature/bug & fix. -->
The `Type.ToTypeString()` introduced with the `Guard` API lacks support for nested types, pointer types and byref types.
## PR Type
What kind of change does this PR introduce?
<!-- Please uncomment one or more that apply to this PR. -->
<!-- - Bugfix -->
<!-- - Feature -->
<!-- - Code style update (formatting) -->
<!-- - Refactoring (no functional changes, no api changes) -->
<!-- - Build or CI related changes -->
<!-- - Documentation content changes -->
<!-- - Sample app changes -->
<!-- - Other... Please describe: -->
## What is the current behavior?
<!-- Please describe the current behavior that you are modifying, or link to a relevant issue. -->
The extension doesn't work properly when used with nested, pointer or byref types.
It will either crash or just return the wrong formatted type (eg. the declaring type instead of the nested type).
## What is the new behavior?
<!-- Describe how was this issue resolved or changed? -->
The extension now works correctly with all sorts of nested, pointer and byref types 🎉
## PR Checklist
Please check if your PR fulfills the following requirements:
- [X] Tested code with current [supported SDKs](../readme.md#supported)
- [ ] ~~Pull Request has been submitted to the documentation repository [instructions](..\contributing.md#docs).~~
- [ ] ~~Sample in sample app has been added / updated (for bug fixes / features)~~
- [ ] ~~Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/windows-toolkit/WindowsCommunityToolkit-design-assets)~~
- [X] Tests for the changes have been added (for bug fixes / features) (if applicable)
- [X] Header has been added to all new source files (run *build/UpdateHeaders.bat*)
- [X] Contains **NO** breaking changes
