FIR IDE: rework KtCall to work with error cals

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/CallInfo.kt

@@ -1,30 +0,0 @@
-/*
- * Copyright 2010-2020 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.idea.frontend.api
-
-import org.jetbrains.kotlin.idea.frontend.api.symbols.*
-
-sealed class CallInfo {
-    abstract val isSuspendCall: Boolean
-    abstract val targetFunction: KtFunctionLikeSymbol?
-}
-
-data class VariableAsFunctionCallInfo(val target: KtVariableLikeSymbol, override val isSuspendCall: Boolean) : CallInfo() {
-    override val targetFunction: KtFunctionLikeSymbol? = null
-}
-
-data class VariableAsFunctionLikeCallInfo(val target: KtVariableLikeSymbol, val invokeFunction: KtFunctionSymbol) : CallInfo() {
-    override val isSuspendCall: Boolean get() = invokeFunction.isSuspend
-    override val targetFunction get() = invokeFunction
-}
-
-data class FunctionCallInfo(override val targetFunction: KtFunctionLikeSymbol) : CallInfo() {
-    override val isSuspendCall: Boolean
-        get() = when (targetFunction) {
-            is KtFunctionSymbol -> targetFunction.isSuspend
-            else -> false
-        }
-}

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/KtAnalysisSession.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.idea.frontend.api
 
 import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.idea.frontend.api.calls.KtCall
 import org.jetbrains.kotlin.idea.frontend.api.components.*
 import org.jetbrains.kotlin.idea.frontend.api.scopes.*
 import org.jetbrains.kotlin.idea.frontend.api.symbols.*
@@ -118,9 +119,9 @@ abstract class KtAnalysisSession(override val token: ValidityToken) : ValidityTo
 
     fun <S : KtSymbol> KtSymbolPointer<S>.restoreSymbol(): S? = restoreSymbol(this@KtAnalysisSession)
 
-    fun KtCallExpression.resolveCall(): CallInfo? = callResolver.resolveCall(this)
+    fun KtCallExpression.resolveCall(): KtCall? = callResolver.resolveCall(this)
 
-    fun KtBinaryExpression.resolveCall(): CallInfo? = callResolver.resolveCall(this)
+    fun KtBinaryExpression.resolveCall(): KtCall? = callResolver.resolveCall(this)
 
     fun KtReference.resolveToSymbols(): Collection<KtSymbol> {
         check(this is KtSymbolBasedReference) { "To get reference symbol the one should be KtSymbolBasedReference" }

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/calls/KtCall.kt

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2010-2020 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.idea.frontend.api.calls
+
+import org.jetbrains.kotlin.idea.frontend.api.diagnostics.KtDiagnostic
+import org.jetbrains.kotlin.idea.frontend.api.symbols.*
+
+/**
+ * Represents direct or indirect (via invoke) function call from Kotlin code
+ */
+sealed class KtCall {
+    abstract val isErrorCall: Boolean
+}
+
+/**
+ * Call using `()` of some variable of functional type, e.g.,
+ *
+ * fun x(f: () -> Int) {
+ *    f() // functional type call
+ * }
+ */
+class KtFunctionalTypeVariableCall(val target: KtVariableLikeSymbol) : KtCall() {
+    override val isErrorCall: Boolean get() = false
+}
+
+/**
+ * Direct or indirect call of function declared by user
+ */
+sealed class KtDeclaredFunctionCall : KtCall() {
+    abstract val targetFunction: KtCallTarget
+    override val isErrorCall: Boolean
+        get() = targetFunction is KtErrorCallTarget
+}
+
+/**
+ * Call using () on variable on some non-functional type, considers that `invoke` function is declared somewhere
+ *
+ * fun x(y: Int) {
+ *    y() // variable with invoke function call
+ * }
+ *
+ * fun Int.invoke() {}
+ */
+class KtVariableWithInvokeFunctionCall(
+    val target: KtVariableLikeSymbol,
+    val invokeFunction: KtCallTarget,
+) : KtDeclaredFunctionCall() {
+    override val targetFunction: KtCallTarget get() = invokeFunction
+}
+
+/**
+ * Simple function call, e.g.,
+ *
+ * x.toString() // function call
+ */
+data class KtFunctionCall(override val targetFunction: KtCallTarget) : KtDeclaredFunctionCall()
+
+/**
+ * Represents function(s) in which call was resolved,
+ * Can be success [KtSuccessCallTarget] in this case there only one such function
+ * Or erroneous [KtErrorCallTarget] in this case there can be any count of candidates
+ */
+sealed class KtCallTarget {
+    abstract val candidates: Collection<KtFunctionLikeSymbol>
+}
+
+/**
+ * Success call of [symbol]
+ */
+class KtSuccessCallTarget(val symbol: KtFunctionLikeSymbol) : KtCallTarget() {
+    override val candidates: Collection<KtFunctionLikeSymbol>
+        get() = listOf(symbol)
+}
+
+/**
+ * Function all with errors, possible candidates are [candidates]
+ */
+class KtErrorCallTarget(override val candidates: Collection<KtFunctionLikeSymbol>, val diagnostic: KtDiagnostic) : KtCallTarget()

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/calls/ktCallUtils.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2020 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.idea.frontend.api.calls
+
+import org.jetbrains.kotlin.idea.frontend.api.symbols.KtFunctionLikeSymbol
+
+fun KtCallTarget.getSuccessCallSymbolOrNull(): KtFunctionLikeSymbol? = when (this) {
+    is KtSuccessCallTarget -> symbol
+    is KtErrorCallTarget -> null
+}
+
+inline fun <reified S : KtFunctionLikeSymbol> KtCall.isSuccessCallOf(predicate: (S) -> Boolean): Boolean {
+    if (this !is KtFunctionCall) return false
+    val symbol = targetFunction.getSuccessCallSymbolOrNull() ?: return false
+    if (symbol !is S) return false
+    return predicate(symbol)
+}

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/components/KtCallResolver.kt

@@ -5,11 +5,11 @@
 
 package org.jetbrains.kotlin.idea.frontend.api.components
 
-import org.jetbrains.kotlin.idea.frontend.api.CallInfo
+import org.jetbrains.kotlin.idea.frontend.api.calls.KtCall
 import org.jetbrains.kotlin.psi.KtBinaryExpression
 import org.jetbrains.kotlin.psi.KtCallExpression
 
 abstract class KtCallResolver : KtAnalysisSessionComponent() {
-    abstract fun resolveCall(call: KtCallExpression): CallInfo?
-    abstract fun resolveCall(call: KtBinaryExpression): CallInfo?
+    abstract fun resolveCall(call: KtCallExpression): KtCall?
+    abstract fun resolveCall(call: KtBinaryExpression): KtCall?
 }

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/diagnostics/KtDiagnostic.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2020 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.idea.frontend.api.diagnostics
+
+sealed class KtDiagnostic {
+    abstract val message: String
+}
+
+data class KtSimpleDiagnostic(override val message: String): KtDiagnostic()