Annotation with backticks in the package name unrecognized

[ting-yuan]

Reported by Toshihiro Nakamura:

When using KSP2, it seems that the SymbolProcessor does not recognize annotations that contain backticks in the package name. For example, consider the following annotation:

@`org.komapper.annotation`.KomapperEntity
data class Employee(val id: Int)

The annotation is recognized by the SymbolProcessor in version 2.0.21-1.0.25, but it is not recognized in version 2.0.21-1.0.26.

[ting-yuan]

@`com.example`.Anno is probably invalid on JVM according to the Kotlin language spec:

Kotlin supports escaping identifiers by enclosing any sequence of characters into backtick (`) characters, allowing to use any name as an identifier. This allows not only using non-alphanumeric characters (like @ or #) in names, but also using keywords like if or when as identifiers. Actual set of characters that is allowed to be escaped may, however, be a subject to platform restrictions. Consult particular platform sections for details.

Note: for example, the following characters are not allowed in identifiers used as declaration names on the JVM platform even when escaped due to JVM restrictions: ., ;, [, ], /, <, >, :, \ .

At least, I cannot find the definition of the interpretation of the dot inside backtick quotes. Whether `com.example` is illegal or is treated like `com`.`excample` depends on (the underlying Kotlin compiler) implementation.

@`com`.example.Anno and @com.`example`.Anno work fine.