Add readonly modifier to internal static members

[xtqqczze]

PR Summary

• Add readonly modifier to internal static members.

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[powercode]

Why readonly instead of const?

[xtqqczze]

@powercode I considered a change to const would have uncertain benefit, and might be a risk, because all variables which consume const would then be hardcoded.

In theory since the fields are internal there should no danger in using const, but I was not confident there could be no issues.

https://blogs.msdn.microsoft.com/armenk/2013/03/01/how-dangerous-can-be-public-const-while-upgrading-or-fixing-a-component/

Armen Kirakosyan's blog

How dangerous can be “public const” while upgrading or fixing a component.

During my investigation I have noticed a source of potential problem for product upgrade where dev team should fix a bug or upgrade a component and distribute it. So what will happen when during fix/upgrade process (I will call it upgrade) a value which was declared as public const was changed. For clear understanding we...

[ghost]

This pull request has been automatically marked as Review Needed because it has been there has not been any activity for 7 days.
Mainainer, Please provide feedback and/or mark it as Waiting on Author

[xtqqczze]

rebased to resolve merge conflicts

[xtqqczze]

@iSazonov I have made amendments, can you review?

[xtqqczze]

@iSazonov force pushed to remove name changes, but now we have StyleCop rule violations, SA1304NonPrivateReadonlyFieldsMustBeginWithUpperCaseLetter

[xtqqczze]

rebased to resolve merge conflicts

[iSazonov]

force pushed to remove name changes, but now we have StyleCop rule violations, SA1304NonPrivateReadonlyFieldsMustBeginWithUpperCaseLetter

Our code convention is :

Use _camelCase to name internal and private fields and use readonly where possible.

So we have a conflict with StyleCop rule. But we can not use the rule without changing our code convention.
/cc @daxian-dbw for conclusion.

[xtqqczze]

So we have a conflict with StyleCop rule. But we can not use the rule without changing our code convention.
/cc @daxian-dbw for conclusion.

@iSazonov I have opened #12819 so we can make a general decision on the code convention.

[xtqqczze]

@iSazonov I am not sure why CodeFactor finds NonPrivateReadonlyFieldsMustBeginWithUpperCaseLetter issues as the rule is not enabled in setting.stylecop or the default rule-set.

[iSazonov]

@xtqqczze Perhaps it is CodeFactor effiect.

[ghost]

Hello @iSazonov!

Because this pull request has the AutoMerge label, I will be glad to assist with helping to merge this pull request once all check-in policies pass.

p.s. you can customize the way I help with merging this pull request, such as holding this pull request until a specific person approves. Simply @mention me (@msftbot) and give me an instruction to get started! Learn more here.

[xtqqczze]

@xtqqczze Perhaps it is CodeFactor effiect.

@iSazonov The rule is not present in the CodeFactor default rule-set.

[xtqqczze]

@iSazonov I have PR #12855 to disable NonPrivateReadonlyFieldsMustBeginWithUpperCaseLetter in Settings.StyleCop.

[ghost]

🎉v7.1.0-preview.4 has been released which incorporates this pull request.:tada:

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