From bf08359f0dbd14984bd95c777744b7d88637a564 Mon Sep 17 00:00:00 2001
From: Ilya Matveev <ilya.matveev@jetbrains.com>
Date: Fri, 6 Oct 2017 11:34:25 +0300
Subject: [PATCH] unit-tests: Report error on test functions with incorrect
 signature

---
 .../kotlin/backend/konan/lower/TestProcessor.kt   | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/TestProcessor.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/TestProcessor.kt
index f44d1b2d3c3..0c02d3512bb 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/TestProcessor.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/TestProcessor.kt
@@ -230,6 +230,20 @@ internal class TestProcessor (val context: KonanBackendContext) {
             }
         }
 
+        fun IrFunction.checkFunctionSignature() {
+            // Test runner requires test functions to have the following signature: () -> Unit.
+            if (descriptor.returnType != context.builtIns.unitType) {
+                context.reportCompilationError(
+                        "Test function must return Unit: ${descriptor.fqNameSafe}", irFile, this
+                )
+            }
+            if (descriptor.valueParameters.isNotEmpty()) {
+                context.reportCompilationError(
+                        "Test function must have no arguments: ${descriptor.fqNameSafe}", irFile, this
+                )
+            }
+        }
+
         // TODO: Use symbols instead of containingDeclaration when such information is available.
         override fun visitFunction(declaration: IrFunction) {
             val symbol = declaration.symbol
@@ -239,6 +253,7 @@ internal class TestProcessor (val context: KonanBackendContext) {
             if (kinds.isEmpty()) {
                 return
             }
+            declaration.checkFunctionSignature()
 
             when (owner) {
                 is PackageFragmentDescriptor -> topLevelFunctions.registerFunction(symbol, kinds)