Unused symbol: secondary constructors are also under analysis #KT-10812 Fixed

idea/idea-analysis/src/org/jetbrains/kotlin/idea/KotlinBundle.properties

@@ -52,6 +52,7 @@ unused.object=Object ''{0}'' is never used
 unused.function=Function ''{0}'' is never used
 unused.property=Property ''{0}'' is never used
 unused.type.parameter=Type parameter ''{0}'' is never used
+unused.constructor=Constructor is never used
 
 unused.receiver.parameter=Receiver parameter is never used
 unused.receiver.parameter.remove=Remove redundant receiver parameter

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

@@ -129,11 +129,13 @@ class UnusedSymbolInspection : AbstractKotlinInspection() {
 
     override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean, session: LocalInspectionToolSession): PsiElementVisitor {
         return object : KtVisitorVoid() {
-            override fun visitNamedDeclaration(declaration: KtNamedDeclaration) {
+            override fun visitDeclaration(declaration: KtDeclaration) {
+                if (declaration !is KtNamedDeclaration) return
                 val messageKey = when (declaration) {
                     is KtClass -> "unused.class"
                     is KtObjectDeclaration -> "unused.object"
                     is KtNamedFunction -> "unused.function"
+                    is KtSecondaryConstructor -> "unused.constructor"
                     is KtProperty, is KtParameter -> "unused.property"
                     is KtTypeParameter -> "unused.type.parameter"
                     else -> return
@@ -143,7 +145,7 @@ class UnusedSymbolInspection : AbstractKotlinInspection() {
 
                 // Simple PSI-based checks
                 if (declaration is KtObjectDeclaration && declaration.isCompanion()) return // never mark companion object as unused (there are too many reasons it can be needed for)
-                if (declaration.name == null) return
+                declaration.name ?: return
                 if (declaration is KtEnumEntry) return
                 if (declaration.hasModifier(KtTokens.OVERRIDE_KEYWORD)) return
                 if (declaration is KtProperty && declaration.isLocal) return
@@ -162,8 +164,9 @@ class UnusedSymbolInspection : AbstractKotlinInspection() {
                 if (hasNonTrivialUsages(declaration)) return
                 if (declaration is KtClassOrObject && classOrObjectHasTextUsages(declaration)) return
 
+                val psiElement = declaration.nameIdentifier ?: (declaration as? KtConstructor<*>)?.getConstructorKeyword() ?: return
                 val problemDescriptor = holder.manager.createProblemDescriptor(
-                        declaration.nameIdentifier!!,
+                        psiElement,
                         null,
                         KotlinBundle.message(messageKey, declaration.name),
                         ProblemHighlightType.LIKE_UNUSED_SYMBOL,
@@ -301,7 +304,9 @@ class UnusedSymbolInspection : AbstractKotlinInspection() {
 }
 
 class SafeDeleteFix(val declaration: KtDeclaration) : LocalQuickFix {
-    override fun getName() = QuickFixBundle.message("safe.delete.text", declaration.name)
+    override fun getName() =
+            if (declaration is KtConstructor<*>) "Safe delete constructor"
+            else QuickFixBundle.message("safe.delete.text", declaration.name)
 
     override fun getFamilyName() = "Safe delete"
 

idea/testData/inspections/unusedSymbol/function/inspectionData/expected.xml

@@ -69,4 +69,13 @@
     <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
     <description>Class 'WithNativeAnnotation' is never used</description>
   </problem>
+
+  <problem>
+    <file>secondaryConstructor.kt</file>
+    <line>3</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/secondaryConstructor.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused symbol</problem_class>
+    <description>Constructor is never used</description>
+  </problem>
 </problems>

idea/testData/inspections/unusedSymbol/function/secondaryConstructor.kt

@@ -0,0 +1,10 @@
+class Owner(val name: String, val code: Int) {
+    constructor(name: String): this(name, 0)
+    constructor(code: Int): this("", code)
+}
+
+@test.anno.EntryPoint
+fun use(): Int {
+    val owner = Owner("xyz")
+    return if (owner.name != "") owner.code else -1
+}

idea/testData/quickfix/removeUnused/unusedConstructor.kt

@@ -0,0 +1,4 @@
+// "Safe delete constructor" "true"
+class Owner(val x: Int) {
+    <caret>constructor(): this(42)
+}

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

@@ -0,0 +1,3 @@
+// "Safe delete constructor" "true"
+class Owner(val x: Int) {
+}

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

@@ -6442,6 +6442,12 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             doTest(fileName);
         }
 
+        @TestMetadata("unusedConstructor.kt")
+        public void testUnusedConstructor() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/removeUnused/unusedConstructor.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("unusedFunction.kt")
         public void testUnusedFunction() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/removeUnused/unusedFunction.kt");