From 4aacb15872333b56baacd0fa74547aa7ad115d39 Mon Sep 17 00:00:00 2001
From: Ilya Kirillov <ilya.kirillov@jetbrains.com>
Date: Wed, 13 Feb 2019 16:06:35 +0300
Subject: [PATCH] New J2K: Add support of lambda expressions in
 LowerNullabilityInFunctionParametersConversion

---
 ...llabilityInFunctionParametersConversion.kt | 47 +++++++++++++++----
 1 file changed, 38 insertions(+), 9 deletions(-)

diff --git a/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/LowerNullabilityInFunctionParametersConversion.kt b/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/LowerNullabilityInFunctionParametersConversion.kt
index 497c357a363..e687ee102e5 100644
--- a/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/LowerNullabilityInFunctionParametersConversion.kt
+++ b/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/LowerNullabilityInFunctionParametersConversion.kt
@@ -5,23 +5,31 @@
 
 package org.jetbrains.kotlin.nj2k.conversions
 
-import org.jetbrains.kotlin.nj2k.ConversionContext
 import org.jetbrains.kotlin.j2k.ast.Nullability
+import org.jetbrains.kotlin.nj2k.ConversionContext
+import org.jetbrains.kotlin.nj2k.isEquals
 import org.jetbrains.kotlin.nj2k.tree.*
 import org.jetbrains.kotlin.nj2k.tree.impl.JKFieldSymbol
+import org.jetbrains.kotlin.nj2k.tree.impl.JKKtSpreadOperator
 import org.jetbrains.kotlin.nj2k.tree.impl.JKTypeElementImpl
+import org.jetbrains.kotlin.utils.addToStdlib.cast
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 class LowerNullabilityInFunctionParametersConversion(private val context: ConversionContext) : RecursiveApplicableConversionBase() {
     override fun applyToElement(element: JKTreeElement): JKTreeElement {
-        if (element !is JKMethod) return recurse(element)
-        val scopes =
-            listOfNotNull(
-                element.block,
-                (element as? JKKtConstructor)?.delegationCall
-            ) + element.parameters.mapNotNull {
-                if (it.initializer !is JKStubExpression) it.initializer else null
+        if (element !is JKMethod && element !is JKLambdaExpression) return recurse(element)
+        val (parameters, scopes) =
+            when (element) {
+                is JKMethod -> element.parameters to
+                        listOfNotNull(
+                            element.block,
+                            (element as? JKKtConstructor)?.delegationCall
+                        ) + element.parameters.mapNotNull { if (it.initializer !is JKStubExpression) it.initializer else null }
+                is JKLambdaExpression -> element.parameters to listOf(element.statement)
+                else -> return recurse(element)
             }
-        for (parameter in element.parameters) {
+
+        for (parameter in parameters) {
             if (parameter.type.type.nullability != Nullability.Default) continue
             if (parameter.hasNotNullUsages(scopes)) {
                 parameter.type = JKTypeElementImpl(parameter.type.type.updateNullability(Nullability.NotNull))
@@ -48,6 +56,27 @@ class LowerNullabilityInFunctionParametersConversion(private val context: Conver
                         return element
                     }
                 }
+                is JKPrefixExpression -> {
+                    if (element.expression.safeAs<JKFieldAccessExpression>()?.identifier == parameterSymbol
+                        && element.operator is JKKtSpreadOperator
+                    ) {
+                        found = true
+                        return element
+                    }
+                }
+                is JKFieldAccessExpression -> {
+                    if (element.identifier == parameterSymbol
+                        && element.parent is JKBinaryExpression
+                        && element.parent.cast<JKBinaryExpression>().let {
+                            !it.operator.isEquals()
+                                    && (it.left.type(context.symbolProvider)?.asPrimitiveType() != null
+                                    || it.right.type(context.symbolProvider)?.asPrimitiveType() != null)
+                        }
+                    ) {
+                        found = true
+                        return element
+                    }
+                }
             }
             return recurse(element)
         }