Remove parentheses after deleting the last unused constructor parameter

So #KT-16636 Fixed

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

@@ -58,6 +58,7 @@ import org.jetbrains.kotlin.idea.findUsages.KotlinFindUsagesHandlerFactory
 import org.jetbrains.kotlin.idea.findUsages.handlers.KotlinFindClassUsagesHandler
 import org.jetbrains.kotlin.idea.highlighter.markers.hasActualsFor
 import org.jetbrains.kotlin.idea.imports.importableFqName
+import org.jetbrains.kotlin.idea.quickfix.RemoveUnusedFunctionParameterFix
 import org.jetbrains.kotlin.idea.references.mainReference
 import org.jetbrains.kotlin.idea.references.resolveMainReferenceToDescriptors
 import org.jetbrains.kotlin.idea.search.usagesSearch.dataClassComponentFunction
@@ -386,9 +387,14 @@ class SafeDeleteFix(declaration: KtDeclaration) : LocalQuickFix {
     override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
         val declaration = descriptor.psiElement.getStrictParentOfType<KtDeclaration>() ?: return
         if (!FileModificationService.getInstance().prepareFileForWrite(declaration.containingFile)) return
-        ApplicationManager.getApplication().invokeLater(
-                { SafeDeleteHandler.invoke(project, arrayOf(declaration), false) },
-                ModalityState.NON_MODAL
-        )
+        if (declaration is KtParameter && declaration.parent is KtParameterList && declaration.parent?.parent is KtFunction) {
+            RemoveUnusedFunctionParameterFix(declaration).invoke(project, declaration.findExistingEditor(), declaration.containingKtFile)
+        }
+        else {
+            ApplicationManager.getApplication().invokeLater(
+                    { SafeDeleteHandler.invoke(project, arrayOf(declaration), false) },
+                    ModalityState.NON_MODAL
+            )
+        }
     }
 }

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

@@ -18,14 +18,16 @@ package org.jetbrains.kotlin.idea.quickfix
 
 import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.descriptors.MemberDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.diagnostics.Diagnostic
 import org.jetbrains.kotlin.diagnostics.Errors
-import org.jetbrains.kotlin.idea.caches.resolve.unsafeResolveToDescriptor
-import org.jetbrains.kotlin.psi.KtFile
-import org.jetbrains.kotlin.psi.KtFunctionLiteral
-import org.jetbrains.kotlin.psi.KtNamedFunction
-import org.jetbrains.kotlin.psi.KtParameter
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
+import org.jetbrains.kotlin.idea.util.application.runWriteAction
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.startOffset
+import org.jetbrains.kotlin.resolve.BindingContext
 
 class RemoveUnusedFunctionParameterFix(parameter: KtParameter) : KotlinQuickFixAction<KtParameter>(parameter) {
     override fun getFamilyName() = ChangeFunctionSignatureFix.FAMILY_NAME
@@ -36,8 +38,23 @@ class RemoveUnusedFunctionParameterFix(parameter: KtParameter) : KotlinQuickFixA
 
     override fun invoke(project: Project, editor: Editor?, file: KtFile) {
         val element = element ?: return
-        val parameterDescriptor = element.unsafeResolveToDescriptor() as ValueParameterDescriptor
-        ChangeFunctionSignatureFix.runRemoveParameter(parameterDescriptor, element)
+        val primaryConstructor = element.parent?.parent as? KtPrimaryConstructor
+        val parameterList = element.parent as? KtParameterList
+        if (primaryConstructor != null && parameterList?.parameters?.size == 1 &&
+            (primaryConstructor.getContainingClassOrObject().resolveToDescriptorIfAny() as? MemberDescriptor)?.isExpect == false) {
+            runWriteAction {
+                parameterList.delete()
+            }
+        }
+        else {
+            val context = element.analyze()
+            val parameterDescriptor = context[BindingContext.VALUE_PARAMETER, element] as? ValueParameterDescriptor ?: return
+            ChangeFunctionSignatureFix.runRemoveParameter(parameterDescriptor, element)
+            val nextParameter = parameterList?.parameters?.getOrNull(parameterDescriptor.index)
+            if (editor != null && nextParameter != null) {
+                editor.caretModel.moveToOffset(nextParameter.startOffset)
+            }
+        }
     }
 
     companion object : KotlinSingleIntentionActionFactory() {

idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter.kt

@@ -0,0 +1,3 @@
+// "Remove parameter 'a'" "true"
+
+class Foo(<caret>a: String)

idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter.kt.after

@@ -0,0 +1,3 @@
+// "Remove parameter 'a'" "true"
+
+class Foo<caret>

idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter2.kt

@@ -0,0 +1,3 @@
+// "Remove parameter 'a'" "true"
+
+class Foo(<caret>a: String, b: String)

idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter2.kt.after

@@ -0,0 +1,3 @@
+// "Remove parameter 'a'" "true"
+
+class Foo(<caret>b: String)

idea/testData/quickfix/removeUnused/unusedPropertyAsConstructorParameter.kt.after

@@ -1,2 +1,2 @@
 // "Safe delete 'property'" "true"
-class UnusedPropertyAsConstructorParameter()
+class UnusedPropertyAsConstructorParameter<caret>

idea/testData/quickfix/removeUnused/unusedPropertyAsConstructorParameter2.kt

@@ -0,0 +1,2 @@
+// "Safe delete 'property'" "true"
+class UnusedPropertyAsConstructorParameter(val <caret>property: String, val foo: String)

idea/testData/quickfix/removeUnused/unusedPropertyAsConstructorParameter2.kt.after

@@ -0,0 +1,2 @@
+// "Safe delete 'property'" "true"
+class UnusedPropertyAsConstructorParameter(<caret>val foo: String)

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

@@ -1423,6 +1423,18 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/changeSignature/removeUnusedParameter.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("removeUnusedPrimaryConstructorParameter.kt")
+        public void testRemoveUnusedPrimaryConstructorParameter() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("removeUnusedPrimaryConstructorParameter2.kt")
+        public void testRemoveUnusedPrimaryConstructorParameter2() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/changeSignature/removeUnusedPrimaryConstructorParameter2.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("idea/testData/quickfix/changeToLabeledReturn")
@@ -9071,6 +9083,12 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             doTest(fileName);
         }
 
+        @TestMetadata("unusedPropertyAsConstructorParameter2.kt")
+        public void testUnusedPropertyAsConstructorParameter2() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/removeUnused/unusedPropertyAsConstructorParameter2.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("unusedTypeParameter.kt")
         public void testUnusedTypeParameter() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/removeUnused/unusedTypeParameter.kt");