Unused object.

unusedButEntryPointMain for class was actually a wrong test: it didn't check anything, because objects are were not checked for unusedness before.

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

@@ -118,6 +118,7 @@ goto.super.property.chooser.title=Choose super property
 goto.super.class.chooser.title=Choose super class or interface
 
 unused.class=Class ''{0}'' is never used
+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

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

@@ -59,6 +59,8 @@ import com.intellij.codeInsight.daemon.QuickFixBundle
 import com.intellij.codeInsight.FileModificationService
 import com.intellij.refactoring.safeDelete.SafeDeleteHandler
 import org.jetbrains.kotlin.psi.JetPsiUtil
+import org.jetbrains.kotlin.psi.JetObjectDeclaration
+import org.jetbrains.kotlin.psi.JetClassOrObject
 
 public class UnusedSymbolInspection : AbstractKotlinInspection() {
     private val javaInspection = UnusedDeclarationInspection()
@@ -83,6 +85,7 @@ public class UnusedSymbolInspection : AbstractKotlinInspection() {
             override fun visitNamedDeclaration(declaration: JetNamedDeclaration) {
                 val messageKey = when (declaration) {
                     is JetClass -> "unused.class"
+                    is JetObjectDeclaration -> "unused.object"
                     is JetNamedFunction -> "unused.function"
                     is JetProperty, is JetParameter -> "unused.property"
                     is JetTypeParameter -> "unused.type.parameter"
@@ -104,7 +107,7 @@ public class UnusedSymbolInspection : AbstractKotlinInspection() {
 
                 // Main checks: finding reference usages && text usages
                 if (hasNonTrivialUsages(declaration)) return
-                if (declaration is JetClass && classHasTextUsages(declaration)) return
+                if (declaration is JetClassOrObject && classOrObjectHasTextUsages(declaration)) return
 
                 holder.registerProblem(
                         declaration.getNameIdentifier(),
@@ -118,23 +121,23 @@ public class UnusedSymbolInspection : AbstractKotlinInspection() {
 
     private fun isEntryPoint(declaration: JetNamedDeclaration): Boolean {
         val lightElement: PsiElement? = when (declaration) {
-            is JetClass ->  declaration.toLightClass()
+            is JetClassOrObject -> declaration.toLightClass()
             is JetNamedFunction -> LightClassUtil.getLightClassMethod(declaration)
             else -> return false
         }
         return lightElement != null && javaInspection.isEntryPoint(lightElement)
     }
 
-    private fun classHasTextUsages(klass: JetClass): Boolean {
+    private fun classOrObjectHasTextUsages(classOrObject: JetClassOrObject): Boolean {
         var hasTextUsages = false
 
         // Finding text usages
-        if (klass.getUseScope() is GlobalSearchScope) {
+        if (classOrObject.getUseScope() is GlobalSearchScope) {
-            val findClassUsagesHandler = KotlinFindClassUsagesHandler(klass, KotlinFindUsagesHandlerFactory(klass.getProject()))
+            val findClassUsagesHandler = KotlinFindClassUsagesHandler(classOrObject, KotlinFindUsagesHandlerFactory(classOrObject.getProject()))
             findClassUsagesHandler.processUsagesInText(
-                    klass,
+                    classOrObject,
                     { hasTextUsages = true; false },
-                    GlobalSearchScope.projectScope(klass.getProject())
+                    GlobalSearchScope.projectScope(classOrObject.getProject())
             )
         }
 

idea/testData/inspections/unusedSymbol/class/unusedButEntryPointMain.kt

@@ -1,5 +0,0 @@
-object EntryPoint {
-    fun main(args: Array<String>) {
-
-    }
-}

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

@@ -0,0 +1,34 @@
+<problems>
+  <problem>
+    <file>unused.kt</file>
+    <line>1</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/unused.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
+    <description>Object 'A' is never used</description>
+  </problem>
+  <problem>
+    <file>usedOnlyInside.kt</file>
+    <line>1</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/usedOnlyInside.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
+    <description>Object 'A' is never used</description>
+  </problem>
+  <problem>
+    <file>usedInTextByShortName.kt</file>
+    <line>3</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/usedInTextByShortName.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
+    <description>Object 'UsedInTextByShortName' is never used</description>
+  </problem>
+  <problem>
+    <file>usedOnlyInImport.kt</file>
+    <line>3</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/usedOnlyInImport.kt" />
+    <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused Symbol</problem_class>
+    <description>Object 'A' is never used</description>
+  </problem>
+</problems>

idea/testData/inspections/unusedSymbol/object/inspectionData/inspections.test

@@ -0,0 +1 @@
+// INSPECTION_CLASS: org.jetbrains.kotlin.idea.inspections.UnusedSymbolInspection

idea/testData/inspections/unusedSymbol/object/unused.kt

@@ -0,0 +1 @@
+object A

idea/testData/inspections/unusedSymbol/object/unusedButEntryPointMain.kt

@@ -0,0 +1,11 @@
+package entryPoint
+
+// WITH_RUNTIME
+
+import kotlin.platform.platformStatic
+
+object EntryPoint {
+    platformStatic public fun main(args: Array<String>) {
+
+    }
+}

idea/testData/inspections/unusedSymbol/object/used.kt

@@ -0,0 +1,5 @@
+object A
+
+fun main(args: Array<String>) {
+    val x = A
+}

idea/testData/inspections/unusedSymbol/object/usedInJava.java

@@ -0,0 +1,5 @@
+class RandomJavaClass {
+    void f() {
+        foo.UsedInJava.INSTANCE$.bar();
+    }
+}

idea/testData/inspections/unusedSymbol/object/usedInJava.kt

@@ -0,0 +1,6 @@
+package foo
+
+object UsedInJava {
+    fun bar() {
+    }
+}

idea/testData/inspections/unusedSymbol/object/usedInText.kt

@@ -0,0 +1,3 @@
+package foo
+
+object UsedInTextOnly

idea/testData/inspections/unusedSymbol/object/usedInText.txt

@@ -0,0 +1 @@
+foo.UsedInTextOnly

idea/testData/inspections/unusedSymbol/object/usedInTextByShortName.kt

@@ -0,0 +1,3 @@
+package foo
+
+object UsedInTextByShortName

idea/testData/inspections/unusedSymbol/object/usedInTextByShortName.txt

@@ -0,0 +1 @@
+UsedInTextByShortName

idea/testData/inspections/unusedSymbol/object/usedInXml.kt

@@ -0,0 +1,3 @@
+package foo
+
+object UsedInXmlOnly

idea/testData/inspections/unusedSymbol/object/usedInXml.xml

@@ -0,0 +1 @@
+<a b="foo.UsedInXmlOnly"/>

idea/testData/inspections/unusedSymbol/object/usedOnlyInImport.kt

@@ -0,0 +1,4 @@
+import A
+
+object A {
+}

idea/testData/inspections/unusedSymbol/object/usedOnlyInside.kt

@@ -0,0 +1,9 @@
+object A {
+    fun foo() {
+        A.bar()
+    }
+
+    fun bar() {
+        A.foo()
+    }
+}

idea/tests/org/jetbrains/kotlin/idea/codeInsight/JetInspectionTestGenerated.java

@@ -90,6 +90,12 @@ public class JetInspectionTestGenerated extends AbstractJetInspectionTest {
             doTest(fileName);
         }
 
+        @TestMetadata("unusedSymbol/object/inspectionData/inspections.test")
+        public void testUnusedSymbol_object_inspectionData_Inspections_test() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("idea/testData/inspections/unusedSymbol/object/inspectionData/inspections.test");
+            doTest(fileName);
+        }
+
         @TestMetadata("unusedSymbol/parameter/inspectionData/inspections.test")
         public void testUnusedSymbol_parameter_inspectionData_Inspections_test() throws Exception {
             String fileName = JetTestUtils.navigationMetadata("idea/testData/inspections/unusedSymbol/parameter/inspectionData/inspections.test");