JS backend: fix KT-6037 (default arguments in simple function with expression as body)

#KT-6037 Fixed

js/js.tests/test/org/jetbrains/k2js/test/semantics/DefaultArgumentsTest.java

@@ -71,4 +71,8 @@ public class DefaultArgumentsTest extends SingleFileTranslationTest {
     public void testComplexExpressionAsDefaultArgument() throws Exception {
         checkFooBoxIsOk();
     }
+
+    public void testDefaultArgumentsInFunctionWithExpressionAsBody() throws Exception {
+        checkFooBoxIsOk();
+    }
 }

js/js.translator/src/org/jetbrains/k2js/translate/utils/FunctionBodyTranslator.java

@@ -85,7 +85,7 @@ public final class FunctionBodyTranslator extends AbstractTranslator {
         JetExpression jetBodyExpression = declaration.getBodyExpression();
         assert jetBodyExpression != null : "Cannot translate a body of an abstract function.";
         JsBlock jsBlock = new JsBlock(setDefaultValueForArguments(descriptor, context()));
-        jsBlock.getStatements().addAll(mayBeWrapWithReturn(Translation.translateExpression(jetBodyExpression, context())).getStatements());
+        jsBlock.getStatements().addAll(mayBeWrapWithReturn(Translation.translateExpression(jetBodyExpression, context(), jsBlock)).getStatements());
         return jsBlock;
     }
 

js/js.translator/testData/defaultArguments/cases/defaultArgumentsInFunctionWithExpressionAsBody.kt

@@ -0,0 +1,17 @@
+// KT-6037: KT-6037 Javascript default function arguments fill code generated in wrong order on method without "return keyword"
+package foo
+
+inline fun id<T>(x: T) = x
+
+fun test(arg: Int = 10) = id(arg)
+
+fun foo(value: String = "K") = "O" + try { value } catch(e: Exception) { "..." }
+
+fun box(): String {
+
+    assertEquals(10, test())
+    assertEquals(100, test(100))
+    assertEquals("OK", foo())
+
+    return "OK"
+}