From 2aa20d003d71a10494316bae8b16804e2c05a872 Mon Sep 17 00:00:00 2001
From: Ilya Kirillov <ilya.kirillov@jetbrains.com>
Date: Mon, 10 Jun 2019 10:03:36 +0300
Subject: [PATCH] New J2K: convert vararg type parameter Java length call to
 Kotlin size call

---
 .../conversions/ArrayOperationsConversion.kt     | 16 ++++++++++++++--
 .../newJ2k/varArg/varargLengthAccess.java        |  4 ++++
 .../testData/newJ2k/varArg/varargLengthAccess.kt |  3 +++
 ...ToKotlinConverterSingleFileTestGenerated.java |  5 +++++
 4 files changed, 26 insertions(+), 2 deletions(-)
 create mode 100644 nj2k/testData/newJ2k/varArg/varargLengthAccess.java
 create mode 100644 nj2k/testData/newJ2k/varArg/varargLengthAccess.kt

diff --git a/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/ArrayOperationsConversion.kt b/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/ArrayOperationsConversion.kt
index 2af9aa840b2..70bf89c95ba 100644
--- a/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/ArrayOperationsConversion.kt
+++ b/nj2k/src/org/jetbrains/kotlin/nj2k/conversions/ArrayOperationsConversion.kt
@@ -13,14 +13,15 @@ package org.jetbrains.kotlin.nj2k.conversions
 import org.jetbrains.kotlin.nj2k.NewJ2kConverterContext
 import org.jetbrains.kotlin.nj2k.tree.*
 import org.jetbrains.kotlin.nj2k.tree.impl.JKFieldAccessExpressionImpl
+import org.jetbrains.kotlin.nj2k.tree.impl.JKUniverseFieldSymbol
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 
 class ArrayOperationsConversion(private val context: NewJ2kConverterContext) : RecursiveApplicableConversionBase() {
     override fun applyToElement(element: JKTreeElement): JKTreeElement {
         if (element !is JKQualifiedExpression) return recurse(element)
         val selector = element.selector as? JKFieldAccessExpression ?: return recurse(element)
-        if (element.receiver.type(context.symbolProvider) !is JKJavaArrayType) return recurse(element)
-        if (selector.identifier.name == "length") {
+        if (element.receiver.isArrayOrVarargTypeParameter() && selector.identifier.name == "length") {
             val sizeCall =
                 JKFieldAccessExpressionImpl(
                     context.symbolProvider.provideFieldSymbol("kotlin.Array.size")
@@ -29,4 +30,15 @@ class ArrayOperationsConversion(private val context: NewJ2kConverterContext) : R
         }
         return recurse(element)
     }
+
+    private fun JKExpression.isArrayOrVarargTypeParameter(): Boolean {
+        if (type(context.symbolProvider) is JKJavaArrayType) return true
+        val parameter =
+            safeAs<JKFieldAccessExpression>()
+                ?.identifier
+                .safeAs<JKUniverseFieldSymbol>()
+                ?.target
+                ?.safeAs<JKParameter>()
+        return parameter?.isVarArgs == true
+    }
 }
\ No newline at end of file
diff --git a/nj2k/testData/newJ2k/varArg/varargLengthAccess.java b/nj2k/testData/newJ2k/varArg/varargLengthAccess.java
new file mode 100644
index 00000000000..7e11682c34e
--- /dev/null
+++ b/nj2k/testData/newJ2k/varArg/varargLengthAccess.java
@@ -0,0 +1,4 @@
+//method
+int nya(Object... objs) {
+    return objs.length;
+}
\ No newline at end of file
diff --git a/nj2k/testData/newJ2k/varArg/varargLengthAccess.kt b/nj2k/testData/newJ2k/varArg/varargLengthAccess.kt
new file mode 100644
index 00000000000..00f91f7b0d0
--- /dev/null
+++ b/nj2k/testData/newJ2k/varArg/varargLengthAccess.kt
@@ -0,0 +1,3 @@
+fun nya(vararg objs: Any?): Int {
+    return objs.size
+}
\ No newline at end of file
diff --git a/nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java b/nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java
index 284812cbf85..e673cbe54be 100644
--- a/nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java
+++ b/nj2k/tests/org/jetbrains/kotlin/nj2k/NewJavaToKotlinConverterSingleFileTestGenerated.java
@@ -4744,6 +4744,11 @@ public class NewJavaToKotlinConverterSingleFileTestGenerated extends AbstractNew
         public void testEllipsisTypeSingleParams() throws Exception {
             runTest("nj2k/testData/newJ2k/varArg/ellipsisTypeSingleParams.java");
         }
+
+        @TestMetadata("varargLengthAccess.java")
+        public void testVarargLengthAccess() throws Exception {
+            runTest("nj2k/testData/newJ2k/varArg/varargLengthAccess.java");
+        }
     }
 
     @TestMetadata("nj2k/testData/newJ2k/whileStatement")