From a1477983ba427acf026f5db80224a65fdde70844 Mon Sep 17 00:00:00 2001
From: Ivan Kylchik <ivan.kylchik@jetbrains.com>
Date: Wed, 23 Nov 2022 12:39:25 +0100
Subject: [PATCH] Properly handle vararg interpretation for classic frontend

#KT-55108 Fixed
---
 .../FirBlackBoxCodegenTestGenerated.java      |  6 ++++
 .../interpreter/checker/IrConstTransformer.kt | 12 +++-----
 .../codegen/box/annotations/kt55108.kt        | 28 +++++++++++++++++++
 .../IrBlackBoxCodegenTestGenerated.java       |  6 ++++
 4 files changed, 44 insertions(+), 8 deletions(-)
 create mode 100644 compiler/testData/codegen/box/annotations/kt55108.kt

diff --git a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java
index 82b1fe4da0a..d899808ea3f 100644
--- a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java
+++ b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java
@@ -257,6 +257,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/annotations/kt25489.kt");
         }
 
+        @Test
+        @TestMetadata("kt55108.kt")
+        public void testKt55108() throws Exception {
+            runTest("compiler/testData/codegen/box/annotations/kt55108.kt");
+        }
+
         @Test
         @TestMetadata("mustBeDocumented.kt")
         public void testMustBeDocumented() throws Exception {
diff --git a/compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/checker/IrConstTransformer.kt b/compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/checker/IrConstTransformer.kt
index b31cf9aa438..25cef772342 100644
--- a/compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/checker/IrConstTransformer.kt
+++ b/compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/checker/IrConstTransformer.kt
@@ -119,14 +119,10 @@ class IrConstTransformer(
         if (elements.isEmpty()) return this
         val newIrVararg = IrVarargImpl(this.startOffset, this.endOffset, this.type, this.varargElementType)
         for (element in this.elements) {
-            when (element) {
-                is IrExpression -> newIrVararg.addElement(element.transformSingleArg(this.varargElementType))
-                is IrSpreadElement -> {
-                    when (val expression = element.expression) {
-                        is IrVararg -> expression.transformVarArg().elements.forEach { newIrVararg.addElement(it) }
-                        else -> newIrVararg.addElement(expression.transformSingleArg(this.varargElementType))
-                    }
-                }
+            when (val arg = (element as? IrSpreadElement)?.expression ?: element) {
+                is IrVararg -> arg.transformVarArg().elements.forEach { newIrVararg.addElement(it) }
+                is IrExpression -> newIrVararg.addElement(arg.transformSingleArg(this.varargElementType))
+                else -> newIrVararg.addElement(arg)
             }
         }
         return newIrVararg
diff --git a/compiler/testData/codegen/box/annotations/kt55108.kt b/compiler/testData/codegen/box/annotations/kt55108.kt
new file mode 100644
index 00000000000..7581f8c058f
--- /dev/null
+++ b/compiler/testData/codegen/box/annotations/kt55108.kt
@@ -0,0 +1,28 @@
+// TARGET_BACKEND: JVM_IR
+// WITH_REFLECT
+
+annotation class A(vararg val strings: String)
+
+@A(*arrayOf("foo", "bar"), "baz")
+class B
+
+@A("baz", *arrayOf("foo", "bar"), "xyz")
+class C
+
+@A(*arrayOf("foo", "bar", "xyz"))
+class D
+
+@A("foo", "baz", "bar")
+class E
+
+@A(*arrayOf("foo", "bar"), *arrayOf("baz", "xyz"))
+class F
+
+fun box(): String {
+    assert((B::class.annotations.single() as A).strings.contentEquals(arrayOf("foo", "bar", "baz"))) { "Fail1" }
+    assert((C::class.annotations.single() as A).strings.contentEquals(arrayOf("baz", "foo", "bar", "xyz"))) { "Fail 2" }
+    assert((D::class.annotations.single() as A).strings.contentEquals(arrayOf("foo", "bar", "xyz"))) { "Fail 3" }
+    assert((E::class.annotations.single() as A).strings.contentEquals(arrayOf("foo", "baz", "bar"))) { "Fail 4" }
+    assert((F::class.annotations.single() as A).strings.contentEquals(arrayOf("foo", "bar", "baz", "xyz"))) { "Fail 5" }
+    return "OK"
+}
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
index 8ee1ccf299c..5b04fa7b9cd 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
@@ -257,6 +257,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/annotations/kt25489.kt");
         }
 
+        @Test
+        @TestMetadata("kt55108.kt")
+        public void testKt55108() throws Exception {
+            runTest("compiler/testData/codegen/box/annotations/kt55108.kt");
+        }
+
         @Test
         @TestMetadata("mustBeDocumented.kt")
         public void testMustBeDocumented() throws Exception {