Add quickfix for UNUSED_LAMBDA_EXPRESSION (#867)

Fixes #KT-9757

idea/src/org/jetbrains/kotlin/idea/quickfix/AddRunToLambdaFix.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2010-2016 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.idea.quickfix
+
+import com.intellij.codeInsight.intention.IntentionAction
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.psi.KtFile
+import org.jetbrains.kotlin.psi.KtLambdaExpression
+import org.jetbrains.kotlin.psi.KtPsiFactory
+
+class AddRunToLambdaFix(element: KtLambdaExpression) : KotlinQuickFixAction<KtLambdaExpression>(element) {
+    override fun getText() = "Add 'run' before the lambda expression"
+    override fun getFamilyName() = text
+
+    override fun invoke(project: Project, editor: Editor?, file: KtFile) {
+        val factory = KtPsiFactory(project)
+        element.replace(factory.createExpression("run ${element.text}"))
+    }
+
+    companion object Factory : KotlinIntentionActionsFactory() {
+        override fun doCreateActions(diagnostic: Diagnostic): List<IntentionAction> {
+            val casted = Errors.UNUSED_LAMBDA_EXPRESSION.cast(diagnostic)
+            return listOf(AddRunToLambdaFix(casted.psiElement))
+        }
+    }
+}

idea/src/org/jetbrains/kotlin/idea/quickfix/QuickFixRegistrar.kt

@@ -380,5 +380,7 @@ class QuickFixRegistrar : QuickFixContributor {
         UNRESOLVED_REFERENCE.registerFactory(MakeConstructorParameterPropertyFix)
 
         SUPERTYPE_IS_EXTENSION_FUNCTION_TYPE.registerFactory(ConvertExtensionToFunctionTypeFix)
+
+        UNUSED_LAMBDA_EXPRESSION.registerFactory(AddRunToLambdaFix)
     }
 }

idea/testData/quickfix/addRunBeforeLambda/basic.kt

@@ -0,0 +1,6 @@
+// "Add 'run' before the lambda expression" "true"
+// WITH_RUNTIME
+
+fun foo() {
+    {}<caret>
+}

idea/testData/quickfix/addRunBeforeLambda/basic.kt.after

@@ -0,0 +1,6 @@
+// "Add 'run' before the lambda expression" "true"
+// WITH_RUNTIME
+
+fun foo() {
+    run {}<caret>
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java

@@ -365,6 +365,21 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
         }
     }
 
+    @TestMetadata("idea/testData/quickfix/addRunBeforeLambda")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class AddRunBeforeLambda extends AbstractQuickFixTest {
+        public void testAllFilesPresentInAddRunBeforeLambda() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/addRunBeforeLambda"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), true);
+        }
+
+        @TestMetadata("basic.kt")
+        public void testBasic() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/addRunBeforeLambda/basic.kt");
+            doTest(fileName);
+        }
+    }
+
     @TestMetadata("idea/testData/quickfix/addStarProjections")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)