[Analyzer] Lift arrays of literals to static fields

[stephentoub]

We should consider adding an info-level analyzer that flags cases where arrays of literals are being allocated and recommend they instead be lifted to be stored in static readonly fields. We'll need to experiment a bit to drive down false positive rates, e.g.

• Don't warn if the array is returned out of the method.
• Don't warn if the array is mutated by the method.
• Don't warn if the array is being stored / passed immediately as a ReadOnlySpan<T>.

Related:
#33793

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[ghost]

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Issue Details

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We should consider adding an info-level analyzer that flags cases where arrays of literals are being allocated and recommend they instead be lifted to be stored in static readonly fields. We'll need to experiment a bit to drive down false positive rates, e.g.

• Don't warn if the array is returned out of the method.
• Don't warn if the array is mutated by the method.
• Don't warn if the array is being stored / passed immediately as a ReadOnlySpan<T>.

Related:
#33793

Author:	stephentoub
Assignees:	-
Labels:	area-System.Runtime, untriaged, code-analyzer, code-fixer
Milestone:	-

[buyaa-n]

Isn't it same as Extract array of const to static readonly field?

[steveberdy]

This definitely looks the same to me

[buyaa-n]

Yeah, doesn't see any difference, closing as duplicate