org.jetbrains.kotlin.resolve.checkers.UnderscoreChecker.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2016 JetBrains s.r.o.
*
* 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 org.jetbrains.kotlin.resolve.checkers
import com.intellij.psi.PsiElement
import org.jetbrains.kotlin.config.LanguageFeature
import org.jetbrains.kotlin.config.LanguageVersionSettings
import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
import org.jetbrains.kotlin.descriptors.VariableDescriptor
import org.jetbrains.kotlin.descriptors.impl.FunctionExpressionDescriptor
import org.jetbrains.kotlin.diagnostics.DiagnosticSink
import org.jetbrains.kotlin.diagnostics.Errors
import org.jetbrains.kotlin.psi.*
object UnderscoreChecker : DeclarationChecker {
@JvmOverloads
fun checkIdentifier(
identifier: PsiElement?,
diagnosticHolder: DiagnosticSink,
languageVersionSettings: LanguageVersionSettings,
allowSingleUnderscore: Boolean = false
) {
if (identifier == null || identifier.text.isEmpty()) return
val isValidSingleUnderscore = allowSingleUnderscore && identifier.text == "_"
if (!isValidSingleUnderscore && identifier.text.all { it == '_' }) {
diagnosticHolder.report(Errors.UNDERSCORE_IS_RESERVED.on(identifier))
} else if (isValidSingleUnderscore && !languageVersionSettings.supportsFeature(LanguageFeature.SingleUnderscoreForParameterName)) {
diagnosticHolder.report(
Errors.UNSUPPORTED_FEATURE.on(
identifier,
LanguageFeature.SingleUnderscoreForParameterName to languageVersionSettings
)
)
}
}
@JvmOverloads
fun checkNamed(
declaration: KtNamedDeclaration,
diagnosticHolder: DiagnosticSink,
languageVersionSettings: LanguageVersionSettings,
allowSingleUnderscore: Boolean = false
) {
checkIdentifier(declaration.nameIdentifier, diagnosticHolder, languageVersionSettings, allowSingleUnderscore)
}
override fun check(declaration: KtDeclaration, descriptor: DeclarationDescriptor, context: DeclarationCheckerContext) {
if (declaration is KtProperty && descriptor !is VariableDescriptor) return
if (declaration is KtCallableDeclaration) {
for (parameter in declaration.valueParameters) {
checkNamed(
parameter, context.trace, context.languageVersionSettings,
allowSingleUnderscore = descriptor is FunctionExpressionDescriptor
)
}
}
if (declaration is KtTypeParameterListOwner) {
for (typeParameter in declaration.typeParameters) {
checkNamed(typeParameter, context.trace, context.languageVersionSettings)
}
}
if (declaration !is KtNamedDeclaration) return
checkNamed(declaration, context.trace, context.languageVersionSettings)
}
}