"true" and "false" in smart completion when Boolean? expected

core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java

@@ -903,6 +903,10 @@ public class KotlinBuiltIns {
         return isConstructedFromGivenClassAndNotNullable(type, FQ_NAMES._boolean);
     }
 
+    public static boolean isBooleanOrNullableBoolean(@NotNull JetType type) {
+        return isConstructedFromGivenClass(type, FQ_NAMES._boolean);
+    }
+
     public static boolean isBoolean(@NotNull ClassDescriptor classDescriptor) {
         return FQ_NAMES._boolean.equals(getFqName(classDescriptor));
     }

core/descriptors/src/org/jetbrains/kotlin/types/TypeUtils.kt

@@ -22,12 +22,12 @@ import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
-import org.jetbrains.kotlin.resolve.DescriptorUtils
-import org.jetbrains.kotlin.resolve.scopes.SubstitutingScope
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.JetTypeChecker
 import org.jetbrains.kotlin.utils.toReadOnlyList
-import java.util.*
+import java.util.ArrayDeque
+import java.util.ArrayList
+import java.util.LinkedHashSet
 
 public enum class TypeNullability {
     NOT_NULL,
@@ -53,6 +53,7 @@ fun JetType.isNothing(): Boolean = KotlinBuiltIns.isNothing(this)
 fun JetType.isUnit(): Boolean = KotlinBuiltIns.isUnit(this)
 fun JetType.isAnyOrNullableAny(): Boolean = KotlinBuiltIns.isAnyOrNullableAny(this)
 fun JetType.isBoolean(): Boolean = KotlinBuiltIns.isBoolean(this)
+fun JetType.isBooleanOrNullableBoolean(): Boolean = KotlinBuiltIns.isBooleanOrNullableBoolean(this)
 
 private fun JetType.getContainedTypeParameters(): Collection<TypeParameterDescriptor> {
     val declarationDescriptor = getConstructor().getDeclarationDescriptor()

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/CompletionUtils.kt

@@ -45,7 +45,6 @@ import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.inline.InlineUtil
 import org.jetbrains.kotlin.types.JetType
 import org.jetbrains.kotlin.types.typeUtil.TypeNullability
-import org.jetbrains.kotlin.types.typeUtil.makeNotNullable
 import org.jetbrains.kotlin.types.typeUtil.nullability
 import java.util.ArrayList
 
@@ -204,7 +203,7 @@ fun returnExpressionItems(bindingContext: BindingContext, position: JetElement):
                     if (returnType != null && returnType.nullability() == TypeNullability.NULLABLE) {
                         result.add(createKeywordWithLabelElement("return null", null, addSpace = false))
                     }
-                    if (returnType != null && KotlinBuiltIns.isBoolean(returnType.makeNotNullable())) {
+                    if (returnType != null && KotlinBuiltIns.isBooleanOrNullableBoolean(returnType)) {
                         result.add(createKeywordWithLabelElement("return true", null, addSpace = false))
                         result.add(createKeywordWithLabelElement("return false", null, addSpace = false))
                     }

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/KeywordValues.kt

@@ -20,13 +20,13 @@ import com.intellij.codeInsight.completion.InsertionContext
 import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.lookup.LookupElementBuilder
 import com.intellij.codeInsight.lookup.LookupElementDecorator
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.idea.completion.COMPARISON_TOKENS
 import org.jetbrains.kotlin.idea.completion.ExpectedInfo
 import org.jetbrains.kotlin.idea.completion.fuzzyType
 import org.jetbrains.kotlin.idea.completion.handlers.WithTailInsertHandler
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.types.TypeSubstitutor
+import org.jetbrains.kotlin.types.typeUtil.isBooleanOrNullableBoolean
 
 object KeywordValues {
     public fun addToCollection(collection: MutableCollection<LookupElement>, expectedInfos: Collection<ExpectedInfo>, expressionWithType: JetExpression) {
@@ -52,7 +52,7 @@ object KeywordValues {
 
         if (!skipTrueFalse) {
             val booleanInfoClassifier = { info: ExpectedInfo ->
-                if (info.fuzzyType?.type == KotlinBuiltIns.getInstance().getBooleanType()) ExpectedInfoClassification.match(TypeSubstitutor.EMPTY) else ExpectedInfoClassification.noMatch
+                if (info.fuzzyType?.type?.isBooleanOrNullableBoolean() ?: false) ExpectedInfoClassification.match(TypeSubstitutor.EMPTY) else ExpectedInfoClassification.noMatch
             }
             collection.addLookupElements(null, expectedInfos, booleanInfoClassifier) { LookupElementBuilder.create("true").bold().assignSmartCompletionPriority(SmartCompletionItemPriority.TRUE) }
             collection.addLookupElements(null, expectedInfos, booleanInfoClassifier) { LookupElementBuilder.create("false").bold().assignSmartCompletionPriority(SmartCompletionItemPriority.FALSE) }

idea/idea-completion/testData/smart/NullableBooleanExpected.kt

@@ -0,0 +1,5 @@
+fun foo(): Boolean? = <caret>
+
+// EXIST: { itemText: "true", attributes: "bold" }
+// EXIST: { itemText: "false", attributes: "bold" }
+// EXIST: { itemText: "null", attributes: "bold" }

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JvmSmartCompletionTestGenerated.java

@@ -359,6 +359,12 @@ public class JvmSmartCompletionTestGenerated extends AbstractJvmSmartCompletionT
         doTest(fileName);
     }
 
+    @TestMetadata("NullableBooleanExpected.kt")
+    public void testNullableBooleanExpected() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/smart/NullableBooleanExpected.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("Object.kt")
     public void testObject() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/smart/Object.kt");