From 8497931455797c945a3244943e79018e00642191 Mon Sep 17 00:00:00 2001
From: Alexey Andreev <Alexey.Andreev@jetbrains.com>
Date: Wed, 17 Feb 2016 13:58:12 +0300
Subject: [PATCH] #EA-79158 Fix translation of empty 'when' statement

---
 .../org/jetbrains/kotlin/js/test/semantics/WhenTest.java    | 4 ++++
 .../kotlin/js/translate/expression/WhenTranslator.java      | 4 ++--
 js/js.translator/testData/expression/when/cases/empty.kt    | 6 ++++++
 3 files changed, 12 insertions(+), 2 deletions(-)
 create mode 100644 js/js.translator/testData/expression/when/cases/empty.kt

diff --git a/js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/WhenTest.java b/js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/WhenTest.java
index 82af76b750b..6bbdee65b4b 100644
--- a/js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/WhenTest.java
+++ b/js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/WhenTest.java
@@ -133,4 +133,8 @@ public final class WhenTest extends AbstractExpressionTest {
     public void testWhenStatementWithRangeClause() throws Exception {
         checkFooBoxIsOk();
     }
+
+    public void testEmpty() throws Exception {
+        checkFooBoxIsOk();
+    }
 }
diff --git a/js/js.translator/src/org/jetbrains/kotlin/js/translate/expression/WhenTranslator.java b/js/js.translator/src/org/jetbrains/kotlin/js/translate/expression/WhenTranslator.java
index 425f6d72674..11d1a52aefe 100644
--- a/js/js.translator/src/org/jetbrains/kotlin/js/translate/expression/WhenTranslator.java
+++ b/js/js.translator/src/org/jetbrains/kotlin/js/translate/expression/WhenTranslator.java
@@ -67,7 +67,7 @@ public final class WhenTranslator extends AbstractTranslator {
         }
     }
 
-    private JsStatement translate() {
+    private JsNode translate() {
         if (expressionToMatch != null && JsAstUtils.isEmptyExpression(expressionToMatch)) {
             return JsEmpty.INSTANCE;
         }
@@ -100,7 +100,7 @@ public final class WhenTranslator extends AbstractTranslator {
                 currentIf = nextIf;
             }
         }
-        return resultIf;
+        return resultIf != null ? resultIf : context().getEmptyExpression();
     }
 
     @NotNull
diff --git a/js/js.translator/testData/expression/when/cases/empty.kt b/js/js.translator/testData/expression/when/cases/empty.kt
new file mode 100644
index 00000000000..3d8070629ab
--- /dev/null
+++ b/js/js.translator/testData/expression/when/cases/empty.kt
@@ -0,0 +1,6 @@
+package foo
+
+fun box(): String {
+    when {}
+    return "OK"
+}
\ No newline at end of file