IfThenToElvis & FoldInitializerAndIfToElvis should add new line for long expression

Relates to #KT-19643 #KT-16067

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

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.idea.inspections
 
+import com.intellij.application.options.CodeStyle
 import com.intellij.codeInspection.ProblemHighlightType
 import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.project.Project
@@ -19,6 +20,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.core.setType
+import org.jetbrains.kotlin.idea.intentions.branchedTransformations.elvisPattern
 import org.jetbrains.kotlin.idea.intentions.branchedTransformations.expressionComparedToNull
 import org.jetbrains.kotlin.idea.intentions.branchedTransformations.shouldBeTransformed
 import org.jetbrains.kotlin.idea.intentions.branchedTransformations.textRange
@@ -83,10 +85,8 @@ class FoldInitializerAndIfToElvisInspection : AbstractApplicabilityBasedInspecti
             val commentSaver = CommentSaver(childRangeBefore)
             val childRangeAfter = childRangeBefore.withoutLastStatement()
 
-            val pattern = if (element.then?.hasComments() == true)
-                "$0\n?: $1"
-            else
-                "$0 ?: $1"
+            val margin = CodeStyle.getSettings(element.containingKtFile).defaultRightMargin
+            val pattern = elvisPattern(declaration.textLength + ifNullExpr.textLength + 5 >= margin || element.then?.hasComments() == true)
 
             val elvis = factory.createExpressionByPattern(pattern, initializer, ifNullExpr) as KtBinaryExpression
             if (typeReference != null) {

idea/src/org/jetbrains/kotlin/idea/inspections/branchedTransformations/IfThenToElvisInspection.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.idea.inspections.branchedTransformations
 
+import com.intellij.application.options.CodeStyle
 import com.intellij.codeInspection.ProblemHighlightType
 import com.intellij.codeInspection.ui.MultipleCheckboxOptionsPanel
 import com.intellij.openapi.editor.Editor
@@ -63,14 +64,17 @@ class IfThenToElvisInspection(
             val factory = KtPsiFactory(element)
 
             val commentSaver = CommentSaver(element, saveLineBreaks = false)
+            val margin = CodeStyle.getSettings(element.containingKtFile).defaultRightMargin
+
 
             val elvis = runWriteAction {
                 val replacedBaseClause = ifThenToSelectData.replacedBaseClause(factory)
+                val negatedClause = ifThenToSelectData.negatedClause!!
                 val newExpr = element.replaced(
                     factory.createExpressionByPattern(
-                        "$0 ?: $1",
+                        elvisPattern(replacedBaseClause.textLength + negatedClause.textLength + 5 >= margin),
                         replacedBaseClause,
-                        ifThenToSelectData.negatedClause!!
+                        negatedClause
                     )
                 )
 

idea/src/org/jetbrains/kotlin/idea/intentions/branchedTransformations/IfThenUtils.kt

@@ -177,6 +177,8 @@ fun KtExpression.isStableVal(context: BindingContext = this.analyze()): Boolean
     return this.toDataFlowValue(context)?.kind == DataFlowValue.Kind.STABLE_VALUE
 }
 
+fun elvisPattern(newLine: Boolean): String = if (newLine) "$0\n?: $1" else "$0 ?: $1"
+
 private fun KtExpression.toDataFlowValue(context: BindingContext): DataFlowValue? {
     val expressionType = this.getType(context) ?: return null
     val dataFlowValueFactory = this.getResolutionFacade().frontendService<DataFlowValueFactory>()

idea/testData/inspectionsLocal/branched/ifThenToElvis/longLine.kt

@@ -0,0 +1,13 @@
+fun maybeFoo(): String? {
+    return "foo"
+}
+
+val xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx = maybeFoo()
+
+fun main() {
+    val c = if (xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx != null)<caret> {
+        xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+    } else {
+        "abcdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdf"
+    }
+}

idea/testData/inspectionsLocal/branched/ifThenToElvis/longLine.kt.after

@@ -0,0 +1,10 @@
+fun maybeFoo(): String? {
+    return "foo"
+}
+
+val xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx = maybeFoo()
+
+fun main() {
+    val c = xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+            ?: "abcdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdfdf"
+}

idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName.kt

@@ -0,0 +1,6 @@
+fun foo(): Any {
+    val yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy = 7
+    val xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx = 24
+    if (xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx<caret> == null) return yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
+    return 42
+}

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

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

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

@@ -332,6 +332,11 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
                 runTest("idea/testData/inspectionsLocal/branched/ifThenToElvis/lhsNotEqualsNull.kt");
             }
 
+            @TestMetadata("longLine.kt")
+            public void testLongLine() throws Exception {
+                runTest("idea/testData/inspectionsLocal/branched/ifThenToElvis/longLine.kt");
+            }
+
             @TestMetadata("missingElseClause.kt")
             public void testMissingElseClause() throws Exception {
                 runTest("idea/testData/inspectionsLocal/branched/ifThenToElvis/missingElseClause.kt");
@@ -3798,6 +3803,11 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/IsSuperTypeFake.kt");
         }
 
+        @TestMetadata("LongName.kt")
+        public void testLongName() throws Exception {
+            runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/LongName.kt");
+        }
+
         @TestMetadata("MultiStatementBlock.kt")
         public void testMultiStatementBlock() throws Exception {
             runTest("idea/testData/inspectionsLocal/foldInitializerAndIfToElvis/MultiStatementBlock.kt");