[LSG] Objects logging using @ operator in logging source generator attribute

[vpetrusevici]

Description

Hi! Looks like it's impossible to use @ in message template, but it's important for loggers like Serilog, NLog, etc.

Reproduction Steps

I tried to add this:

[LoggerMessage(0, LogLevel.Debug, "MMC request sent {@request}")]
partial void LogRequestSent(RequestRequest request);

and i received this error:

Template '@request' is not provided as argument to the logging method	

using @request in params doesn't change anything.

Expected behavior

Operator @ should be ignored in params names comparison.

Actual behavior

Error appears.

Regression?

No response

Known Workarounds

No response

Configuration

.NET 7 rc2
Visual Studio 2022 preview 6.0

Other information

No response

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Issue Details

---

Description

Hi! Looks like it's impossible to use @ in message template, but it's important for loggers like Serilog, NLog, etc.

Reproduction Steps

I tried to add this:

[LoggerMessage(0, LogLevel.Debug, "MMC request sent {@request}")]
partial void LogRequestSent(RequestRequest request);

and i received this error:

using @request in params doesn't change anything.

Expected behavior

Operator @ should be ignored in params names comparison.

Actual behavior

Error appears.

Regression?

No response

Known Workarounds

No response

Configuration

.NET 7 rc2
Visual Studio 2022 preview 6.0

Other information

No response

Author:	vpetrusevici
Assignees:	-
Labels:	untriaged, area-Extensions-Logging
Milestone:	-

[maryamariyan]

do you have a small sample using serilog with this?

[vpetrusevici]

@maryamariyan Just created https://github.com/vpetrusevici/SerilogSourceGenExample
You should use @ operator to force object json serialization or $ to use .ToString(), but it's impossible with source generation

[vpetrusevici]

You can also see examples for serilog on their page https://serilog.net/

[tarekgh]

Fixed by #79038