Better indent in else-if editing (KT-14601)

#KT-14601 Fixed

(cherry picked from commit 25d6d61)

idea/formatter/src/org/jetbrains/kotlin/idea/formatter/KotlinCommonBlock.kt

@@ -157,6 +157,13 @@ abstract class KotlinCommonBlock(
             return ChildAttributes(Indent.getNoneIndent(), null)
         }
 
+        if (type == KtNodeTypes.IF) {
+            val elseBlock = mySubBlocks?.getOrNull(newChildIndex)
+            if (elseBlock is ASTBlock && elseBlock.node.elementType == KtTokens.ELSE_KEYWORD) {
+                return ChildAttributes.DELEGATE_TO_NEXT_CHILD
+            }
+        }
+
         return when (type) {
             in CODE_BLOCKS, KtNodeTypes.WHEN, KtNodeTypes.IF, KtNodeTypes.FOR, KtNodeTypes.WHILE, KtNodeTypes.DO_WHILE -> ChildAttributes(Indent.getNormalIndent(), null)
 

idea/tests/org/jetbrains/kotlin/idea/editor/TypedHandlerTest.kt

@@ -557,6 +557,53 @@ class TypedHandlerTest : LightCodeInsightTestCase() {
         )
     }
 
+    fun testIndentBeforeElseWithBlock() {
+        doCharTypeTest(
+                '\n',
+                """
+                |fun test(b: Boolean) {
+                |    if (b) {
+                |    }<caret>
+                |    else if (!b) {
+                |    }
+                |}
+                """,
+                """
+                |fun test(b: Boolean) {
+                |    if (b) {
+                |    }
+                |    <caret>
+                |    else if (!b) {
+                |    }
+                |}
+                """
+        )
+    }
+
+    fun testIndentBeforeElseWithoutBlock() {
+        doCharTypeTest(
+                '\n',
+                """
+                |fun test(b: Boolean) {
+                |    if (b)
+                |        foo()<caret>
+                |    else {
+                |    }
+                |}
+                """,
+                """
+                |fun test(b: Boolean) {
+                |    if (b)
+                |        foo()
+                |    <caret>
+                |    else {
+                |    }
+                |}
+                """
+        )
+    }
+
+
     fun testMoveThroughGT() {
         LightPlatformCodeInsightTestCase.configureFromFileText("a.kt", "val a: List<Set<Int<caret>>>")
         EditorTestUtil.performTypingAction(LightPlatformCodeInsightTestCase.getEditor(), '>')