Provide a Code Fix for CA1873 to Automatically Generate LoggerMessageAttribute Methods

[Varorbc]

Problem Description

The .NET code analysis rule CA1873: Avoid possible expensive logging correctly identifies performance‑sensitive logging patterns. However, the analyzer currently does not provide a corresponding Code Fix to help developers automatically migrate these logging calls to the recommended LoggerMessageAttribute or LoggerMessage.Define pattern.

For projects with a large number of ILogger.LogXXX calls, manually converting each log statement is time‑consuming and error‑prone.

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Requested Feature

Please consider adding an automatic Code Fix Provider for CA1873 that can transform a standard logging call into a generated LoggerMessageAttribute method.

Example

Original code

_logger.LogInformation("User {UserId} logged in", userId);

Expected auto‑fix

[LoggerMessage(EventId = 0, Level = LogLevel.Information, Message = "User {UserId} logged in")]
static partial void UserLoggedIn(ILogger logger, string userId);

UserLoggedIn(_logger, userId);

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Why this feature is important

• CA1873 encourages using source‑generated logging for better performance, but the migration path is currently manual.
• Large codebases may contain hundreds or thousands of logging statements, making manual conversion impractical.
• A built‑in Code Fix would significantly improve developer productivity and accelerate adoption of high‑performance logging patterns.

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Additional Suggestions (optional)

• Auto‑generated EventId could default to 0 or prompt the user to adjust it.
• Support applying the fix to an entire document or project.
• Optionally detect and consolidate repeated log messages into a single generated method.

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[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• [Analyzer] Replacing direct LoggerExtensions.Log* usage with source-generated logging methods #78406

[rosebyte]

Triage: We will take a deeper look at this once we have finished the higher-priority items.

[tarekgh]

@Yun-Ting this is related to what you were planning to do for adding a code fixer for CA1848 too. Where are you with that? is it still in your plan? can you extend your fix to include this one too?

#117999