Avoid generating internal static classes with constant names in Options Source gen

[tarekgh]

The Option Source Generator generates static classes with constant names such as __OptionValidationStaticInstances.__Attributes and __OptionValidationStaticInstances.__Validators. These classes have an internal access modifier, which works well when compiling independent projects. However, issues arise when compiling two libraries that both use the Option Source Generator, and one of the libraries is marked with the InternalsVisibleToAttribute to grant access to the internals of the first library.

In this scenario, a compilation error occurs because the generated static classes exist in two places and are accessible to one of these libraries. This leads to ambiguous references and compiler errors.

To resolve this issue, a fix has been implemented. When compiling with Language version 11 or higher, the file access modifier is used, limiting access to only the file where this class is defined. For earlier language versions, a random suffix is generated and added to the class names.

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Issue Details

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The Option Source Generator generates static classes with constant names such as __Attributes and __Validators. These classes have an internal access modifier, which works well when compiling independent projects. However, issues arise when compiling two libraries that both use the Option Source Generator, and one of the libraries is marked with the InternalsVisibleToAttribute to grant access to the internals of the first library.

In this scenario, a compilation error occurs because the generated static classes exist in two places and are accessible to one of these libraries. This leads to ambiguous references and compiler errors.

To resolve this issue, a fix has been implemented. When compiling with Language version 11 or higher, the file access modifier is used, limiting access to only the file where this class is defined. For earlier language versions, a random suffix is generated and added to the class names.

Author:	tarekgh
Assignees:	tarekgh
Labels:	area-Extensions-Options, source-generator
Milestone:	-

[tarekgh]

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