KspAnnotated.kt
/*
* Copyright 2020 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.room.compiler.processing.ksp
import androidx.room.compiler.processing.XAnnotated
import androidx.room.compiler.processing.XAnnotationBox
import com.google.devtools.ksp.symbol.AnnotationUseSiteTarget
import com.google.devtools.ksp.symbol.KSAnnotated
import com.google.devtools.ksp.symbol.KSAnnotation
import kotlin.reflect.KClass
internal sealed class KspAnnotated(
val env: KspProcessingEnv
) : XAnnotated {
abstract fun annotations(): Sequence<KSAnnotation>
override fun <T : Annotation> toAnnotationBox(annotation: KClass<T>): XAnnotationBox<T>? {
return annotations().firstOrNull {
val qName = it.annotationType.resolve().declaration.qualifiedName?.asString()
qName == annotation.qualifiedName
}?.let {
KspAnnotationBox(
env = env,
annotationClass = annotation.java,
annotation = it
)
}
}
override fun hasAnnotationWithPackage(pkg: String): Boolean {
return annotations().any {
it.annotationType.resolve().declaration.qualifiedName?.getQualifier() == pkg
}
}
override fun hasAnnotation(annotation: KClass<out Annotation>): Boolean {
return annotations().any {
val qName = it.annotationType.resolve().declaration.qualifiedName?.asString()
qName == annotation.qualifiedName
}
}
operator fun plus(other: KspAnnotated): XAnnotated = Combined(env, this, other)
private class KSAnnotatedDelegate(
env: KspProcessingEnv,
private val delegate: KSAnnotated,
private val useSiteFilter: UseSiteFilter
) : KspAnnotated(env) {
override fun annotations(): Sequence<KSAnnotation> {
return delegate.annotations.asSequence().filter {
useSiteFilter.accept(it)
}
}
}
private class NotAnnotated(env: KspProcessingEnv) : KspAnnotated(env) {
override fun annotations(): Sequence<KSAnnotation> {
return emptySequence()
}
}
private class Combined(
env: KspProcessingEnv,
private val first: KspAnnotated,
private val second: KspAnnotated
) : KspAnnotated(env) {
override fun annotations(): Sequence<KSAnnotation> {
return first.annotations() + second.annotations()
}
}
/**
* TODO: The implementation of UseSiteFilter is not 100% correct until
* https://github.com/google/ksp/issues/96 is fixed.
* https://kotlinlang.org/docs/reference/annotations.html
*
* More specifically, when a use site is not defined in an annotation, we need to find the
* declaration of the annotation and decide on the use site based on that.
* Unfortunately, due to KSP issue #96, we cannot yet read values from a `@Target` annotation
* which prevents implementing it correctly.
*
* Current implementation just approximates it which should work for Room.
*/
interface UseSiteFilter {
fun accept(annotation: KSAnnotation): Boolean
private class Impl(
val acceptNull: Boolean,
val acceptedTarget: AnnotationUseSiteTarget
) : UseSiteFilter {
override fun accept(annotation: KSAnnotation): Boolean {
val target = annotation.useSiteTarget
return if (target == null) {
acceptNull
} else {
acceptedTarget == target
}
}
}
companion object {
val FIELD: UseSiteFilter = Impl(true, AnnotationUseSiteTarget.FIELD)
val PROPERTY_GETTER: UseSiteFilter = Impl(false, AnnotationUseSiteTarget.GET)
val PROPERTY_SETTER: UseSiteFilter = Impl(false, AnnotationUseSiteTarget.SET)
val PROPERTY_SETTER_PARAMETER: UseSiteFilter =
Impl(false, AnnotationUseSiteTarget.SETPARAM)
val METHOD_PARAMETER: UseSiteFilter = Impl(true, AnnotationUseSiteTarget.PARAM)
val NO_USE_SITE = object : UseSiteFilter {
override fun accept(annotation: KSAnnotation): Boolean {
return annotation.useSiteTarget == null
}
}
}
}
companion object {
fun create(
env: KspProcessingEnv,
delegate: KSAnnotated?,
filter: UseSiteFilter
): KspAnnotated {
return delegate?.let {
KSAnnotatedDelegate(env, it, filter)
} ?: NotAnnotated(env)
}
}
}