org.jetbrains.kotlin.fir.analysis.checkers.declaration.FirFunctionReturnChecker.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package org.jetbrains.kotlin.fir.analysis.checkers.declaration
import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
import org.jetbrains.kotlin.diagnostics.DiagnosticReporter
import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors
import org.jetbrains.kotlin.diagnostics.reportOn
import org.jetbrains.kotlin.fir.declarations.FirAnonymousFunction
import org.jetbrains.kotlin.fir.declarations.FirConstructor
import org.jetbrains.kotlin.fir.declarations.FirFunction
import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
import org.jetbrains.kotlin.fir.resolve.dfa.cfg.BlockExitNode
import org.jetbrains.kotlin.fir.resolve.dfa.controlFlowGraph
import org.jetbrains.kotlin.fir.types.isNothing
import org.jetbrains.kotlin.fir.types.isUnit
object FirFunctionReturnChecker : FirFunctionChecker() {
override fun check(declaration: FirFunction, context: CheckerContext, reporter: DiagnosticReporter) {
checkHasReturnIfBlock(declaration, reporter, context)
}
private fun checkHasReturnIfBlock(
declaration: FirFunction,
reporter: DiagnosticReporter,
context: CheckerContext
) {
if (declaration is FirPropertyAccessor && declaration.isSetter) return
if (declaration is FirConstructor) return
if (declaration is FirAnonymousFunction && declaration.isLambda) return
if (declaration.returnTypeRef.isUnit || declaration.returnTypeRef.isNothing) return
val graph = declaration.controlFlowGraphReference?.controlFlowGraph ?: return
val blockExitNode = graph.exitNode.previousNodes.lastOrNull { it is BlockExitNode } ?: return
if (!blockExitNode.isDead) {
reporter.reportOn(declaration.source, FirErrors.NO_RETURN_IN_FUNCTION_WITH_BLOCK_BODY, context)
}
}
}