Add braces: don't insert extra line break and move the following comment

#KT-36194 Fixed

idea/src/org/jetbrains/kotlin/idea/intentions/AddBracesIntention.kt

@@ -79,7 +79,9 @@ class AddBracesIntention : SelfTargetingIntention<KtElement>(KtElement::class.ja
         val nextComment = when {
             element is KtDoWhileExpression -> null // bound to the closing while
             element is KtIfExpression && expression === element.then && element.`else` != null -> null // bound to else
-            else -> element.getNextSiblingIgnoringWhitespace().takeIf { it is PsiComment }
+            else -> element.getNextSiblingIgnoringWhitespace().takeIf {
+                it is PsiComment && it.getLineNumber() == element.getLineNumber(start = false)
+            }
         }
 
         val saver = when {

idea/testData/intentions/addBraces/hasCommentOnNextLine.kt

@@ -0,0 +1,13 @@
+fun foo(list: List<String>) {
+    if (true)<caret> println(list)
+
+    // printing...
+    println("hi")
+
+    for (l in list) println(l)
+
+    // printing...
+    println("hi")
+}
+
+fun println(a: Any) {}

idea/testData/intentions/addBraces/hasCommentOnNextLine.kt.after

@@ -0,0 +1,15 @@
+fun foo(list: List<String>) {
+    if (true) {
+        println(list)
+    }
+
+    // printing...
+    println("hi")
+
+    for (l in list) println(l)
+
+    // printing...
+    println("hi")
+}
+
+fun println(a: Any) {}

idea/testData/intentions/addBraces/hasCommentOnNextLine2.kt

@@ -0,0 +1,13 @@
+fun foo(list: List<String>) {
+    if (true) println(list)
+
+    // printing...
+    println("hi")
+
+    for (l in list)<caret> println(l)
+
+    // printing...
+    println("hi")
+}
+
+fun println(a: Any) {}

idea/testData/intentions/addBraces/hasCommentOnNextLine2.kt.after

@@ -0,0 +1,15 @@
+fun foo(list: List<String>) {
+    if (true) println(list)
+
+    // printing...
+    println("hi")
+
+    for (l in list) {
+        println(l)
+    }
+
+    // printing...
+    println("hi")
+}
+
+fun println(a: Any) {}

idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java

@@ -764,6 +764,16 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             runTest("idea/testData/intentions/addBraces/forWithComment.kt");
         }
 
+        @TestMetadata("hasCommentOnNextLine.kt")
+        public void testHasCommentOnNextLine() throws Exception {
+            runTest("idea/testData/intentions/addBraces/hasCommentOnNextLine.kt");
+        }
+
+        @TestMetadata("hasCommentOnNextLine2.kt")
+        public void testHasCommentOnNextLine2() throws Exception {
+            runTest("idea/testData/intentions/addBraces/hasCommentOnNextLine2.kt");
+        }
+
         @TestMetadata("ifElseWithComment.kt")
         public void testIfElseWithComment() throws Exception {
             runTest("idea/testData/intentions/addBraces/ifElseWithComment.kt");