Diff syntax highlighting in MarkdownTextblock

[aalok05]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  <!-- Please search GitHub for a similar issue or PR before submitting -->
[x] Feature request
[ ] Sample app request
[ ] Documentation issue or request
[ ] Question of Support request => Please do not submit support request here, instead see https://github.com/Microsoft/UWPCommunityToolkit/blob/master/contributing.md#question

UserVoice link

https://wpdev.uservoice.com/forums/110705-universal-windows-platform/suggestions/32159233-diff-syntax-highlighting-in-markdowntextblock

Current behavior

Diff syntax highlighting is currently not supported in MarkdownTextblock. This would be useful for GitHub related scenarios.

@@ -52,17 +52,6 @@ 
// Unchanged code 
- // Deleted line 
+ // Added line

Expected behavior

@@ -52,17 +52,6 @@ 
// Unchanged code 
- // Deleted line 
+ // Added line

Environment

Nuget Package(s): 

Package Version(s): 

Windows 10 Build Number:
- [ ] Anniversary Update (14393) 
- [ ] Creators Update (15063)
- [ ] Fall Creators Update (16299)
- [ ] Insider Build (xxxxx)

App min and target version:
- [x] Anniversary Update (14393) 
- [ ] Creators Update (15063)
- [ ] Fall Creators Update (16299)
- [ ] Insider Build (xxxxx)

Device form factor:
- [ ] Desktop
- [ ] Mobile
- [ ] Xbox
- [ ] Surface Hub
- [ ] IoT

Visual Studio 
- [ ] 2017 15.3
- [x] 2017 15.4

[nmetulev]

Great suggestion. Thanks for creating a UserVoice entry. If you are up for it, feel free to submit a PR to add this feature

[aalok05]

Ok I'll start working on a PR 👍

[xied75]

Is this part of Markdown standard? Just curious.

[nmetulev]

There isn't really a markdown standard, commonMark probably being the most common one. Don't believe diff syntax higlighting is in commonMark, but it's used in many markdown implementations.

[WilliamABradley]

This has relevance to #1650

[lucaasrojas]

Whats the current status?

[kbrons]

Closing the issue because of inactivity. Let's reopen if someone wants to work on it.

[nmetulev]

Let's leave this issue open in case someone wants to work on it. I'll mark it as help wanted

[WilliamABradley]

#1650 is now finished, and there is a PR here for this: CommunityToolkit/ColorCode-Universal#3