Use of expressions instead of plain text when converting when's

compiler/frontend/src/org/jetbrains/kotlin/psi/JetPsiFactory.kt

@@ -63,7 +63,7 @@ public class JetPsiFactory(private val project: Project) {
     }
 
     public fun createExpression(text: String): JetExpression {
-        return createProperty("val x = $text").getInitializer()!!
+        return createProperty("val x = $text").getInitializer() ?: error("Failed to create expression from text: '$text'")
     }
 
     public fun createClassLiteral(className: String): JetClassLiteralExpression =

compiler/frontend/src/org/jetbrains/kotlin/psi/JetPsiUnparsingUtils.java

@@ -1,51 +0,0 @@
-/*
- * Copyright 2010-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.psi;
-
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-public class JetPsiUnparsingUtils {
-    private JetPsiUnparsingUtils() {
-    }
-
-    @NotNull
-    public static String toBinaryExpression(@Nullable JetExpression left, @NotNull String op, @Nullable JetElement right) {
-        return toBinaryExpression(JetPsiUtil.getText(left), op, JetPsiUtil.getText(right));
-    }
-
-    @NotNull
-    public static String toBinaryExpression(@NotNull String left, @NotNull String op, @NotNull String right) {
-        return left + " " + op + " " + right;
-    }
-
-    @NotNull
-    public static String parenthesizeIfNeeded(@Nullable JetExpression expression) {
-        String text = JetPsiUtil.getText(expression);
-
-        return (expression instanceof JetParenthesizedExpression ||
-                expression instanceof JetConstantExpression ||
-                expression instanceof JetSimpleNameExpression ||
-                expression instanceof JetDotQualifiedExpression)
-               ? text : "(" + text + ")";
-    }
-
-    @NotNull
-    public static String parenthesizeTextIfNeeded(@NotNull String expressionText) {
-        return (expressionText.startsWith("(") && expressionText.endsWith(")")) ? expressionText : "(" + expressionText + ")";
-    }
-}

compiler/frontend/src/org/jetbrains/kotlin/psi/JetWhenConditionInRange.java

@@ -52,6 +52,7 @@ public class JetWhenConditionInRange extends JetWhenCondition {
         return visitor.visitWhenConditionInRange(this, data);
     }
 
+    @NotNull
     public JetSimpleNameExpression getOperationReference() {
         return (JetSimpleNameExpression) findChildByType(JetNodeTypes.OPERATION_REFERENCE);
     }

compiler/frontend/src/org/jetbrains/kotlin/psi/createByPattern.kt

@@ -72,6 +72,7 @@ public fun JetPsiFactory.createExpressionByPattern(pattern: String, vararg args:
             .filter { args[it.getKey()] is String }
             .flatMap { it.getValue() }
             .map { it.range }
+            .filterNot { it.isEmpty() }
             .sortBy { -it.getStartOffset() }
 
     // reformat whole text except for String arguments (as they can contain user's formatting to be preserved)

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

@@ -23,41 +23,34 @@ import org.jetbrains.kotlin.idea.util.psi.patternMatching.matches
 import org.jetbrains.kotlin.idea.util.psi.patternMatching.toRange
 import org.jetbrains.kotlin.lexer.JetTokens
 import org.jetbrains.kotlin.psi.*
-import org.jetbrains.kotlin.psi.JetPsiUnparsingUtils.parenthesizeIfNeeded
-import org.jetbrains.kotlin.psi.JetPsiUnparsingUtils.toBinaryExpression
 import org.jetbrains.kotlin.psi.psiUtil.*
+import org.jetbrains.kotlin.psi.typeRefHelpers.getTypeReference
 
 public val TRANSFORM_WITHOUT_CHECK: String = "Expression must be checked before applying transformation"
 
-fun JetWhenCondition.toExpressionText(subject: JetExpression?): String {
-    return when (this) {
+fun JetWhenCondition.toExpression(subject: JetExpression?): JetExpression {
+    val factory = JetPsiFactory(this)
+    when (this) {
         is JetWhenConditionIsPattern -> {
             val op = if (isNegated()) "!is" else "is"
-            toBinaryExpression(subject, op, getTypeReference())
+            return factory.createExpressionByPattern("$0 $op $1", subject ?: "_", getTypeReference() ?: "")
         }
-        is JetWhenConditionInRange -> {
-            toBinaryExpression(subject, getOperationReference()!!.getText()!!, getRangeExpression())
-        }
-        is JetWhenConditionWithExpression -> {
-            val conditionExpression = getExpression()
-            if (subject != null) {
-                toBinaryExpression(parenthesizeIfNeeded(subject), "==", parenthesizeIfNeeded(conditionExpression))
-            }
-            else {
-                JetPsiUtil.getText(this)
-            }
-        }
-        else -> {
-            assert(this is JetWhenConditionWithExpression, TRANSFORM_WITHOUT_CHECK)
 
-            val conditionExpression = (this as JetWhenConditionWithExpression).getExpression()
-            if (subject != null) {
-                toBinaryExpression(parenthesizeIfNeeded(subject), "==", parenthesizeIfNeeded(conditionExpression))
+        is JetWhenConditionInRange -> {
+            val op = getOperationReference().getText()
+            return factory.createExpressionByPattern("$0 $op $1", subject ?: "_", getRangeExpression() ?: "")
+        }
+
+        is JetWhenConditionWithExpression -> {
+            return if (subject != null) {
+                factory.createExpressionByPattern("$0 == $1", subject, getExpression() ?: "")
             }
             else {
-                JetPsiUtil.getText(this)
+                getExpression()
             }
         }
+
+        else -> throw IllegalArgumentException("Unknown JetWhenCondition type: $this")
     }
 }
 

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

@@ -18,7 +18,7 @@ package org.jetbrains.kotlin.idea.intentions.branchedTransformations.intentions
 
 import com.intellij.openapi.editor.Editor
 import org.jetbrains.kotlin.idea.intentions.JetSelfTargetingIntention
-import org.jetbrains.kotlin.idea.intentions.branchedTransformations.toExpressionText
+import org.jetbrains.kotlin.idea.intentions.branchedTransformations.toExpression
 import org.jetbrains.kotlin.psi.JetPsiFactory
 import org.jetbrains.kotlin.psi.JetSimpleNameExpression
 import org.jetbrains.kotlin.psi.JetWhenExpression
@@ -46,7 +46,7 @@ public class EliminateWhenSubjectIntention : JetSelfTargetingIntention<JetWhenEx
                 else {
                     for ((i, condition) in entry.getConditions().withIndex()) {
                         if (i > 0) appendFixedText(",")
-                        appendNonFormattedText(condition.toExpressionText(subject))
+                        appendExpression(condition.toExpression(subject))
                     }
                 }
                 appendFixedText("->")

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

@@ -18,7 +18,7 @@ package org.jetbrains.kotlin.idea.intentions.branchedTransformations.intentions
 
 import com.intellij.openapi.editor.Editor
 import org.jetbrains.kotlin.idea.intentions.JetSelfTargetingIntention
-import org.jetbrains.kotlin.idea.intentions.branchedTransformations.toExpressionText
+import org.jetbrains.kotlin.idea.intentions.branchedTransformations.toExpression
 import org.jetbrains.kotlin.psi.*
 
 public class WhenToIfIntention : JetSelfTargetingIntention<JetWhenExpression>(javaClass(), "Replace 'when' with 'if'") {
@@ -32,7 +32,8 @@ public class WhenToIfIntention : JetSelfTargetingIntention<JetWhenExpression>(ja
     }
 
     override fun applyTo(element: JetWhenExpression, editor: Editor) {
-        val ifExpression = JetPsiFactory(element).buildExpression {
+        val factory = JetPsiFactory(element)
+        val ifExpression = factory.buildExpression {
             for ((i, entry) in element.getEntries().withIndex()) {
                 if (i > 0) {
                     appendFixedText("else ")
@@ -43,9 +44,9 @@ public class WhenToIfIntention : JetSelfTargetingIntention<JetWhenExpression>(ja
                     appendFixedText("\n")
                 }
                 else {
-                    val branchConditionText = combineWhenConditions(entry.getConditions(), element.getSubjectExpression())
+                    val condition = factory.combineWhenConditions(entry.getConditions(), element.getSubjectExpression())
                     appendFixedText("if (")
-                    appendNonFormattedText(branchConditionText)
+                    appendExpression(condition)
                     appendFixedText(")")
                     appendExpression(branch)
                     appendFixedText("\n")
@@ -56,14 +57,19 @@ public class WhenToIfIntention : JetSelfTargetingIntention<JetWhenExpression>(ja
         element.replace(ifExpression)
     }
 
-    private fun combineWhenConditions(conditions: Array<JetWhenCondition>, subject: JetExpression?): String {
-        return when (conditions.size()) {
-            0 -> ""
-            1 -> conditions[0].toExpressionText(subject)
+    private fun JetPsiFactory.combineWhenConditions(conditions: Array<JetWhenCondition>, subject: JetExpression?): JetExpression? {
+        when (conditions.size()) {
+            0 -> return null
+
+            1 -> return conditions[0].toExpression(subject)
+
             else -> {
-                conditions
-                        .map { condition -> JetPsiUnparsingUtils.parenthesizeTextIfNeeded(condition.toExpressionText(subject)) }
-                        .joinToString(separator = " || ")
+                return buildExpression {
+                    for ((i, condition) in conditions.withIndex()) {
+                        if (i > 0) appendFixedText("||")
+                        appendExpression(condition.toExpression(subject))
+                    }
+                }
             }
         }
     }

idea/testData/intentions/branched/ifWhen/whenToIf/whenWithMultiConditions.kt.after

@@ -1,5 +1,5 @@
 fun test(n: Int): String {
-    return <caret>if ((n < 0) || (n > 1000)) "unknown"
+    return <caret>if (n < 0 || n > 1000) "unknown"
     else if (n <= 10) "small"
     else if (n <= 100) "average"
     else "big"

idea/testData/intentions/branched/ifWhen/whenToIf/whenWithRangeTestsAndMultiConditions.kt.after

@@ -1,6 +1,6 @@
 fun test(n: Int): String {
-    return <caret>if ((n in 0..5) || (n in 5..10)) "small"
-    else if ((n in 10..50) || (n in 50..100)) "average"
-    else if ((n in 100..500) || (n in 500..1000)) "big"
+    return <caret>if (n in 0..5 || n in 5..10) "small"
+    else if (n in 10..50 || n in 50..100) "average"
+    else if (n in 100..500 || n in 500..1000) "big"
     else "unknown"
 }

idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoEnd.kt

@@ -0,0 +1,7 @@
+fun test(n: Int): String {
+    return <caret>when (n) {
+        is -> "String"
+        in -> "1..10"
+        else -> "unknown"
+    }
+}

idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoEnd.kt.after

@@ -0,0 +1,5 @@
+fun test(n: Int): String {
+    return if (n is ) "String"
+    else if (n in) "1..10"
+    else "unknown"
+}

idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoSubject.kt

@@ -0,0 +1,10 @@
+// ERROR: Expected condition of type kotlin.Boolean
+// ERROR: Expected condition of type kotlin.Boolean
+
+fun test(n: Int): String {
+    return <caret>when {
+        is String -> "String"
+        in 1..10 -> "1..10"
+        else -> "unknown"
+    }
+}

idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoSubject.kt.after

@@ -0,0 +1,8 @@
+// ERROR: Expected condition of type kotlin.Boolean
+// ERROR: Expected condition of type kotlin.Boolean
+
+fun test(n: Int): String {
+    return if (_ is String) "String"
+    else if (_ in 1..10) "1..10"
+    else "unknown"
+}

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

@@ -1732,6 +1732,18 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
                     String fileName = JetTestUtils.navigationMetadata("idea/testData/intentions/branched/ifWhen/whenToIf/whenWithoutSubject.kt");
                     doTest(fileName);
                 }
+
+                @TestMetadata("wrongIsAndInNoEnd.kt")
+                public void testWrongIsAndInNoEnd() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoEnd.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("wrongIsAndInNoSubject.kt")
+                public void testWrongIsAndInNoSubject() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("idea/testData/intentions/branched/ifWhen/whenToIf/wrongIsAndInNoSubject.kt");
+                    doTest(fileName);
+                }
             }
         }