Use pattern value in the summary for the generated regex method.

[pawchen]

Fixes #94760

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Issue Details

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Fixes #94760

Author:	pawchen
Assignees:	-
Labels:	area-System.Text.RegularExpressions
Milestone:	-

[pawchen]

OK, so we're failing the tests with special chars that are not valid XML chars in the pattern, such as 0x00 and 0xFFFF. I think we should use the Regex escape syntax (\unnnn) for those, which happens to be the same C# string escape syntax that was handled by Literal(..).

[pawchen]

The current logic is not quite correct for RegexOptions.IgnorePatternWhitespace, please don't merge yet.

[pawchen]

Wrong direction. As the IgnorePatternWhitespace option can be inlined and being on and off through the pattern. Closing.

[stephentoub]

Thanks, anyway, for your efforts.

[pawchen]

@stephentoub You're welcome. It's a good lesson for me to know the Regex better.