FoldInitializerAndIfToElvis: should not add new line for multiline initializer

#KT-35805 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/FoldInitializerAndIfToElvisInspection.kt

@@ -86,7 +86,8 @@ class FoldInitializerAndIfToElvisInspection : AbstractApplicabilityBasedInspecti
             val childRangeAfter = childRangeBefore.withoutLastStatement()
 
             val margin = CodeStyle.getSettings(element.containingKtFile).defaultRightMargin
-            val pattern = elvisPattern(declaration.textLength + ifNullExpr.textLength + 5 >= margin || element.then?.hasComments() == true)
+            val declarationTextLength = declaration.text.split("\n").lastOrNull()?.trim()?.length ?: 0
+            val pattern = elvisPattern(declarationTextLength + ifNullExpr.textLength + 5 >= margin || element.then?.hasComments() == true)
 
             val elvis = factory.createExpressionByPattern(pattern, initializer, ifNullExpr) as KtBinaryExpression
 

idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName2.kt

@@ -0,0 +1,7 @@
+fun foo(): Any {
+    val yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy = 7
+    val xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+            = 24
+    if (xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx<caret> == null) return yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
+    return 42
+}

idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName2.kt.after

@@ -0,0 +1,6 @@
+fun foo(): Any {
+    val yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy = 7
+    val xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+            = 24 ?: return yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
+    return 42
+}

idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/MultiLineInitializer.kt

@@ -0,0 +1,14 @@
+fun foo(vararg args: String): String? = null
+
+fun test(): Int {
+    val foo = foo(
+        "1111111111",
+        "2222222222",
+        "3333333333",
+        "4444444444",
+        "5555555555"
+    )
+    <caret>if (foo == null) return 0
+
+    return 1
+}

idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/MultiLineInitializer.kt.after

@@ -0,0 +1,13 @@
+fun foo(vararg args: String): String? = null
+
+fun test(): Int {
+    val foo = foo(
+        "1111111111",
+        "2222222222",
+        "3333333333",
+        "4444444444",
+        "5555555555"
+    ) ?: return 0
+
+    return 1
+}

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -4704,6 +4704,16 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName.kt");
         }
 
+        @TestMetadata("LongName2.kt")
+        public void testLongName2() throws Exception {
+            runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName2.kt");
+        }
+
+        @TestMetadata("MultiLineInitializer.kt")
+        public void testMultiLineInitializer() throws Exception {
+            runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/MultiLineInitializer.kt");
+        }
+
         @TestMetadata("MultiStatementBlock.kt")
         public void testMultiStatementBlock() throws Exception {
             runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/MultiStatementBlock.kt");