New Editorconfig UX does not use the correct syntax for updating severity of IDE code style

[mavasani]

Version Used:

Steps to Reproduce:

Change the severity of any code style option, say null propagation in the new editorconfig UX (say bump it to a warning)

Expected Behavior:
Generated editorconfig uses dotnet_diagnostic syntax for severity specification:

dotnet_diagnostic.IDE0031.severity = warning

Actual Behavior:

dotnet_style_null_propagation=true:warning

Generated syntax above is deprecated for severity specification, as the severity suffix is not respected on command line builds. Please see the Severity section under https://docs.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/language-rules#option-format and he discussion in #44201 for details.

@jmarolf As mentioned in #44201 (comment), the editorconfig UX should use the severity specification syntax that works for both in IDE and command line, but the current behavior only works in the IDE. ConfigurationUpdater component that is used in Configure Severity light bulb action already does this the correct way, and also adds a useful comment header:

I was really hoping we re-used the same ConfigurationUpdater component for severity/option changes in the editorconfig file from the editorconfig UX to avoid such inconsistencies. Did we end up rewriting a completely new component for updating editorconfig in the editorconfig UX?

[mavasani]

Tagging @vatsalyaagrawal - I believe this a very critical issue and should be addressed asap. Editorconfig UX and Configure Severity lightbulb action now diverge significantly in how editorconfig gets updated and this adds confusion for the users, plus also causes different IDE gestures to configure editorconfig severity to generate different syntax which has differing behavior on command line. We need to fix this before the deprecated severity syntax starts spreading through more editorconfigs.

[Youssef1313]

Duplicate of #52694

[mavasani]

Thanks @Youssef1313. Agreed that technically it is duplicate. However, I still want to retain this issue as it seems we added a duplicate severity/options configuration component for Editorconfig UX, instead of re-using the one used for Configure Severity lightbulb action. Regardless of how the syntax changes are done, we should only have a single shared component between these two UI gestures to change/update editorconfig.