Raw FIR: set "implicit boolean" result type for some operator calls

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
+import java.util.*
+
 enum class FirOperation(val operator: String = "???") {
     // Binary
     RANGE(".."),
@@ -37,6 +39,10 @@ enum class FirOperation(val operator: String = "???") {
     OTHER;
 
     companion object {
-        val ASSIGNMENTS = setOf(ASSIGN, PLUS_ASSIGN, MINUS_ASSIGN, TIMES_ASSIGN, DIV_ASSIGN, REM_ASSIGN)
+        val ASSIGNMENTS: Set<FirOperation> = EnumSet.of(ASSIGN, PLUS_ASSIGN, MINUS_ASSIGN, TIMES_ASSIGN, DIV_ASSIGN, REM_ASSIGN)
+
+        val BOOLEANS: Set<FirOperation> = EnumSet.of(
+            EQ, NOT_EQ, IDENTITY, NOT_IDENTITY, LT, GT, LT_EQ, GT_EQ, IN, NOT_IN, IS, NOT_IS
+        )
     }
 }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractOperationBasedCall.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. 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.expressions.impl
+
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.expressions.FirOperation
+import org.jetbrains.kotlin.fir.types.FirTypeRef
+import org.jetbrains.kotlin.fir.types.impl.FirImplicitBooleanTypeRef
+import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
+
+abstract class FirAbstractOperationBasedCall(
+    session: FirSession,
+    psi: PsiElement?,
+    val operation: FirOperation
+) : FirAbstractCall(session, psi) {
+    override var typeRef: FirTypeRef = if (operation in FirOperation.BOOLEANS) {
+        FirImplicitBooleanTypeRef(session, null)
+    } else {
+        FirImplicitTypeRefImpl(session, null)
+    }
+}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt

@@ -13,5 +13,5 @@ import org.jetbrains.kotlin.fir.expressions.FirOperatorCall
 class FirOperatorCallImpl(
     session: FirSession,
     psi: PsiElement?,
-    override val operation: FirOperation
-) : FirAbstractCall(session, psi), FirOperatorCall
+    operation: FirOperation
+) : FirAbstractOperationBasedCall(session, psi, operation), FirOperatorCall

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt

@@ -17,11 +17,11 @@ import org.jetbrains.kotlin.fir.visitors.FirTransformer
 class FirTypeOperatorCallImpl(
     session: FirSession,
     psi: PsiElement?,
-    override val operation: FirOperation,
+    operation: FirOperation,
     override var conversionTypeRef: FirTypeRef
-) : FirAbstractCall(session, psi), FirTypeOperatorCall {
+) : FirAbstractOperationBasedCall(session, psi, operation), FirTypeOperatorCall {
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirElement {
         conversionTypeRef = conversionTypeRef.transformSingle(transformer, data)
-        return super<FirAbstractCall>.transformChildren(transformer, data)
+        return super<FirAbstractOperationBasedCall>.transformChildren(transformer, data)
     }
 }