KT-15286: Provide object member extensions in the completion

- Add extensions only when completion of static members is enabled (double ctrl + space and nonempty prefix)
- Add full import for callables with receiver in `LookupElement.decorateAsStaticMember`

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

@@ -339,8 +339,19 @@ class BasicCompletionSession(
                     }
                 }
 
-                if (configuration.staticMembers && callTypeAndReceiver is CallTypeAndReceiver.DEFAULT && prefix.isNotEmpty()) {
-                    staticMembersCompletion.completeFromIndices(indicesHelper(false), collector)
+                if (configuration.staticMembers && prefix.isNotEmpty()) {
+                    if (!receiverTypes.isNullOrEmpty()) {
+                        staticMembersCompletion.completeObjectMemberExtensionsFromIndices(
+                            indicesHelper(false),
+                            receiverTypes.map { it.type },
+                            callTypeAndReceiver.callType,
+                            collector
+                        )
+                    }
+
+                    if (callTypeAndReceiver is CallTypeAndReceiver.DEFAULT) {
+                        staticMembersCompletion.completeFromIndices(indicesHelper(false), collector)
+                    }
                 }
             }
         }

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

@@ -374,6 +374,7 @@ fun LookupElement.decorateAsStaticMember(
     val qualifierPresentation = classDescriptor.name.asString()
 
     return object : LookupElementDecorator<LookupElement>(this) {
+        private val descriptorIsCallableExtension = (memberDescriptor as? CallableDescriptor)?.extensionReceiverParameter != null
         override fun getAllLookupStrings(): Set<String> {
             return if (classNameAsLookupString) setOf(delegate.lookupString, qualifierPresentation) else super.getAllLookupStrings()
         }
@@ -381,7 +382,9 @@ fun LookupElement.decorateAsStaticMember(
         override fun renderElement(presentation: LookupElementPresentation) {
             delegate.renderElement(presentation)
 
-            presentation.itemText = qualifierPresentation + "." + presentation.itemText
+            if (!descriptorIsCallableExtension) {
+                presentation.itemText = qualifierPresentation + "." + presentation.itemText
+            }
 
             val tailText = " (" + DescriptorUtils.getFqName(classDescriptor.containingDeclaration) + ")"
             if (memberDescriptor is FunctionDescriptor) {
@@ -399,7 +402,11 @@ fun LookupElement.decorateAsStaticMember(
             val psiDocumentManager = PsiDocumentManager.getInstance(context.project)
             val file = context.file as KtFile
 
-            val addMemberImport = file.importDirectives.any { !it.isAllUnder && it.importPath?.fqName?.parent() == containerFqName }
+            fun importFromSameParentIsPresent() = file.importDirectives.any {
+                !it.isAllUnder && it.importPath?.fqName?.parent() == containerFqName
+            }
+
+            val addMemberImport = descriptorIsCallableExtension || importFromSameParentIsPresent()
 
             if (addMemberImport) {
                 psiDocumentManager.commitAllDocuments()

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

@@ -26,6 +26,8 @@ import org.jetbrains.kotlin.idea.codeInsight.collectSyntheticStaticMembersAndCon
 import org.jetbrains.kotlin.idea.core.KotlinIndicesHelper
 import org.jetbrains.kotlin.idea.core.targetDescriptors
 import org.jetbrains.kotlin.idea.resolve.ResolutionFacade
+import org.jetbrains.kotlin.idea.util.CallType
+import org.jetbrains.kotlin.idea.util.substituteExtensionIfCallable
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.KtClass
 import org.jetbrains.kotlin.psi.KtFile
@@ -35,6 +37,7 @@ import org.jetbrains.kotlin.resolve.ImportedFromObjectCallableDescriptor
 import org.jetbrains.kotlin.resolve.scopes.DescriptorKindExclude
 import org.jetbrains.kotlin.resolve.scopes.DescriptorKindFilter
 import org.jetbrains.kotlin.resolve.scopes.getDescriptorsFiltered
+import org.jetbrains.kotlin.types.KotlinType
 import java.util.*
 
 class StaticMembersCompletion(
@@ -117,6 +120,19 @@ class StaticMembersCompletion(
         }
     }
 
+    private fun processObjectMemberExtensions(indicesHelper: KotlinIndicesHelper, processor: (CallableDescriptor) -> Unit) {
+        val descriptorKindFilter = DescriptorKindFilter.CALLABLES exclude DescriptorKindExclude.NonExtensions
+        val nameFilter: (String) -> Boolean = { prefixMatcher.prefixMatches(it) }
+
+        val filter = { _: KtNamedDeclaration, _: KtObjectDeclaration -> true }
+
+        indicesHelper.processObjectMembers(descriptorKindFilter, nameFilter, filter) {
+            if (it !in alreadyAdded && it is CallableDescriptor) {
+                processor(it)
+            }
+        }
+    }
+
     private fun KtObjectDeclaration.isTopLevelOrCompanion(): Boolean {
         if (isCompanion()) {
             val owner = parent.parent as? KtClass ?: return false
@@ -134,6 +150,36 @@ class StaticMembersCompletion(
                 .forEach { collector.addElement(it) }
     }
 
+    /**
+     * Collects extensions declared as members in objects into [collector], for example:
+     *
+     * ```
+     * object Obj {
+     *     fun String.foo() {}
+     * }
+     * ```
+     *
+     * `foo` here is object member extension.
+     */
+    fun completeObjectMemberExtensionsFromIndices(
+        indicesHelper: KotlinIndicesHelper,
+        receiverTypes: Collection<KotlinType>,
+        callType: CallType<*>,
+        collector: LookupElementsCollector
+    ) {
+        val factory = decoratedLookupElementFactory(ItemPriority.STATIC_MEMBER)
+        processObjectMemberExtensions(indicesHelper) { objectMemberDescriptor ->
+            val substitutedExtensions = objectMemberDescriptor.substituteExtensionIfCallable(receiverTypes, callType)
+
+            for (substituted in substitutedExtensions) {
+                val lookups = factory.createStandardLookupElementsForDescriptor(substituted, useReceiverTypes = true)
+                lookups.forEach { collector.addElement(it) }
+            }
+
+            collector.flushToResultSet()
+        }
+    }
+
     fun completeFromIndices(indicesHelper: KotlinIndicesHelper, collector: LookupElementsCollector) {
         val factory = decoratedLookupElementFactory(ItemPriority.STATIC_MEMBER)
         processMembersFromIndices(indicesHelper) {

idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectExplicitReceiver.kt

@@ -0,0 +1,16 @@
+class T
+
+class A {
+    companion object {
+        fun T.fooExtension() {}
+        val T.fooProperty get() = 10
+    }
+}
+
+fun usage(t: T) {
+    t.foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooExtension", itemText: "fooExtension" }
+// EXIST: { lookupString: "fooProperty", itemText: "fooProperty" }

idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectImplicitReceiver.kt

@@ -0,0 +1,16 @@
+class T
+
+class A {
+    companion object {
+        fun T.fooExtension() {}
+        val T.fooProperty get() = 10
+    }
+}
+
+fun T.usage() {
+    foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooExtension", itemText: "fooExtension" }
+// EXIST: { lookupString: "fooProperty", itemText: "fooProperty" }

idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeExplicitReceiver.kt

@@ -0,0 +1,35 @@
+interface T
+interface B: T
+interface C: T
+
+object A {
+    fun Any.fooForAny() {}
+
+    fun T.fooForT() {}
+    fun B.fooForB() {}
+    fun C.fooForC() {}
+
+    fun <TT> TT.fooForAnyGeneric() {}
+    fun <TT: T> TT.fooForTGeneric() {}
+    fun <TT: B> TT.fooForBGeneric() {}
+    fun <TT: C> TT.fooForCGeneric() {}
+
+    fun fooNoReceiver() {}
+}
+
+fun usage(b: B) {
+    b.foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooForAny", itemText: "fooForAny" }
+
+// EXIST: { lookupString: "fooForT", itemText: "fooForT" }
+// EXIST: { lookupString: "fooForB", itemText: "fooForB" }
+
+// EXIST: { lookupString: "fooForTGeneric", itemText: "fooForTGeneric" }
+// EXIST: { lookupString: "fooForBGeneric", itemText: "fooForBGeneric" }
+
+// ABSENT: fooForC
+// ABSENT: fooForCGeneric
+// ABSENT: fooNoReceiver

idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeImplicitReceiver.kt

@@ -0,0 +1,36 @@
+interface T
+interface B: T
+interface C: T
+
+object A {
+    fun Any.fooForAny() {}
+
+    fun T.fooForT() {}
+    fun B.fooForB() {}
+    fun C.fooForC() {}
+
+    fun <TT> TT.fooForAnyGeneric() {}
+    fun <TT: T> TT.fooForTGeneric() {}
+    fun <TT: B> TT.fooForBGeneric() {}
+    fun <TT: C> TT.fooForCGeneric() {}
+
+    fun fooNoReceiver() {}
+}
+
+fun B.usage() {
+    foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooForAny", itemText: "fooForAny" }
+
+// EXIST: { lookupString: "fooForT", itemText: "fooForT" }
+// EXIST: { lookupString: "fooForB", itemText: "fooForB" }
+
+// EXIST: { lookupString: "fooForTGeneric", itemText: "fooForTGeneric" }
+// EXIST: { lookupString: "fooForBGeneric", itemText: "fooForBGeneric" }
+
+// EXIST: fooNoReceiver
+
+// ABSENT: fooForC
+// ABSENT: fooForCGeneric

idea/idea-completion/testData/basic/common/extensionMethodInObject/MultipleImplicitReceivers.kt

@@ -0,0 +1,24 @@
+class T
+
+object O {
+    fun A.fooForA() {}
+    fun A.B.fooForB() {}
+    fun A.B.C.fooForC() {}
+    fun T.fooForT() {}
+}
+
+class A {
+    inner class B {
+        fun T.usage() {
+            foo<caret>
+        }
+
+        inner class C {}
+    }
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooForA", itemText: "fooForA" }
+// EXIST: { lookupString: "fooForB", itemText: "fooForB" }
+// EXIST: { lookupString: "fooForT", itemText: "fooForT" }
+// ABSENT: fooForC

idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectExplicitReceiver.kt

@@ -0,0 +1,14 @@
+class T
+
+object A {
+    fun T.fooExtension() {}
+    val T.fooProperty get() = 10
+}
+
+fun usage(t: T) {
+    t.foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooExtension", itemText: "fooExtension" }
+// EXIST: { lookupString: "fooProperty", itemText: "fooProperty" }

idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectImplicitReceiver.kt

@@ -0,0 +1,14 @@
+class T
+
+object A {
+    fun T.fooExtension() {}
+    val T.fooProperty get() = 10
+}
+
+fun T.usage() {
+    foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooExtension", itemText: "fooExtension" }
+// EXIST: { lookupString: "fooProperty", itemText: "fooProperty" }

idea/idea-completion/testData/basic/common/extensionMethodInObject/OverridenExtensionsInObject.kt

@@ -0,0 +1,19 @@
+class T
+
+interface Foo {
+    fun T.fooExtension()
+    val T.fooProperty: Int
+}
+
+object A : Foo {
+    override fun T.fooExtension() {}
+    override val T.fooProperty get() = 10
+}
+
+fun T.usage() {
+    foo<caret>
+}
+
+// INVOCATION_COUNT: 2
+// EXIST: { lookupString: "fooExtension", itemText: "fooExtension" }
+// EXIST: { lookupString: "fooProperty", itemText: "fooProperty" }

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileExplicitReceiver.kt

@@ -0,0 +1,12 @@
+class T {
+    companion object {
+        fun T.foo() {}
+    }
+}
+
+fun usage(t: T) {
+    t.f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileExplicitReceiver.kt.after

@@ -0,0 +1,14 @@
+import T.Companion.foo
+
+class T {
+    companion object {
+        fun T.foo() {}
+    }
+}
+
+fun usage(t: T) {
+    t.foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileImplicitReceiver.kt

@@ -0,0 +1,12 @@
+class T {
+    companion object {
+        fun T.foo() {}
+    }
+}
+
+fun T.usage() {
+    f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileImplicitReceiver.kt.after

@@ -0,0 +1,14 @@
+import T.Companion.foo
+
+class T {
+    companion object {
+        fun T.foo() {}
+    }
+}
+
+fun T.usage() {
+    foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileExplicitReceiver.kt

@@ -0,0 +1,16 @@
+class T
+
+class A {
+    class B {
+        companion object {
+            fun T.foo() {}
+        }
+    }
+}
+
+fun usage(t: T) {
+    t.f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileExplicitReceiver.kt.after

@@ -0,0 +1,18 @@
+import A.B.Companion.foo
+
+class T
+
+class A {
+    class B {
+        companion object {
+            fun T.foo() {}
+        }
+    }
+}
+
+fun usage(t: T) {
+    t.foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileImplicitReceiver.kt

@@ -0,0 +1,16 @@
+class T
+
+class A {
+    class B {
+        companion object {
+            fun T.foo() {}
+        }
+    }
+}
+
+fun T.usage() {
+    f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileImplicitReceiver.kt.after

@@ -0,0 +1,18 @@
+import A.B.Companion.foo
+
+class T
+
+class A {
+    class B {
+        companion object {
+            fun T.foo() {}
+        }
+    }
+}
+
+fun T.usage() {
+    foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileExplicitReceiver.kt

@@ -0,0 +1,14 @@
+class T
+
+object TopLevel {
+    object Nested {
+        fun T.foo() {}
+    }
+}
+
+fun usage(t: T) {
+    t.f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileExplicitReceiver.kt.after

@@ -0,0 +1,16 @@
+import TopLevel.Nested.foo
+
+class T
+
+object TopLevel {
+    object Nested {
+        fun T.foo() {}
+    }
+}
+
+fun usage(t: T) {
+    t.foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileImplicitReceiver.kt

@@ -0,0 +1,14 @@
+class T
+
+object TopLevel {
+    object Nested {
+        fun T.foo() {}
+    }
+}
+
+fun T.usage() {
+    f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileImplicitReceiver.kt.after

@@ -0,0 +1,16 @@
+import TopLevel.Nested.foo
+
+class T
+
+object TopLevel {
+    object Nested {
+        fun T.foo() {}
+    }
+}
+
+fun T.usage() {
+    foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileExplicitReceiver.kt

@@ -0,0 +1,12 @@
+class T
+
+object Extensions {
+    fun T.foo() {}
+}
+
+fun usage(t: T) {
+    t.f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileExplicitReceiver.kt.after

@@ -0,0 +1,14 @@
+import Extensions.foo
+
+class T
+
+object Extensions {
+    fun T.foo() {}
+}
+
+fun usage(t: T) {
+    t.foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileImplicitReceiver.kt

@@ -0,0 +1,12 @@
+class T
+
+object Extensions {
+    fun T.foo() {}
+}
+
+fun T.usage() {
+    f<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileImplicitReceiver.kt.after

@@ -0,0 +1,14 @@
+import Extensions.foo
+
+class T
+
+object Extensions {
+    fun T.foo() {}
+}
+
+fun T.usage() {
+    foo()<caret>
+}
+
+// INVOCATION_COUNT: 2
+// ELEMENT: foo

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

@@ -1229,6 +1229,59 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
             }
         }
 
+        @TestMetadata("idea/idea-completion/testData/basic/common/extensionMethodInObject")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class ExtensionMethodInObject extends AbstractJSBasicCompletionTest {
+            private void runTest(String testDataFilePath) throws Exception {
+                KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
+            }
+
+            public void testAllFilesPresentInExtensionMethodInObject() throws Exception {
+                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/idea-completion/testData/basic/common/extensionMethodInObject"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
+            }
+
+            @TestMetadata("CompanionObjectExplicitReceiver.kt")
+            public void testCompanionObjectExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectExplicitReceiver.kt");
+            }
+
+            @TestMetadata("CompanionObjectImplicitReceiver.kt")
+            public void testCompanionObjectImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectImplicitReceiver.kt");
+            }
+
+            @TestMetadata("CorrectTypeExplicitReceiver.kt")
+            public void testCorrectTypeExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeExplicitReceiver.kt");
+            }
+
+            @TestMetadata("CorrectTypeImplicitReceiver.kt")
+            public void testCorrectTypeImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeImplicitReceiver.kt");
+            }
+
+            @TestMetadata("MultipleImplicitReceivers.kt")
+            public void testMultipleImplicitReceivers() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/MultipleImplicitReceivers.kt");
+            }
+
+            @TestMetadata("ObjectExplicitReceiver.kt")
+            public void testObjectExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectExplicitReceiver.kt");
+            }
+
+            @TestMetadata("ObjectImplicitReceiver.kt")
+            public void testObjectImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectImplicitReceiver.kt");
+            }
+
+            @TestMetadata("OverridenExtensionsInObject.kt")
+            public void testOverridenExtensionsInObject() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/OverridenExtensionsInObject.kt");
+            }
+        }
+
         @TestMetadata("idea/idea-completion/testData/basic/common/extensions")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

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

@@ -1229,6 +1229,59 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
             }
         }
 
+        @TestMetadata("idea/idea-completion/testData/basic/common/extensionMethodInObject")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class ExtensionMethodInObject extends AbstractJvmBasicCompletionTest {
+            private void runTest(String testDataFilePath) throws Exception {
+                KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
+            }
+
+            public void testAllFilesPresentInExtensionMethodInObject() throws Exception {
+                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/idea-completion/testData/basic/common/extensionMethodInObject"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
+            }
+
+            @TestMetadata("CompanionObjectExplicitReceiver.kt")
+            public void testCompanionObjectExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectExplicitReceiver.kt");
+            }
+
+            @TestMetadata("CompanionObjectImplicitReceiver.kt")
+            public void testCompanionObjectImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CompanionObjectImplicitReceiver.kt");
+            }
+
+            @TestMetadata("CorrectTypeExplicitReceiver.kt")
+            public void testCorrectTypeExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeExplicitReceiver.kt");
+            }
+
+            @TestMetadata("CorrectTypeImplicitReceiver.kt")
+            public void testCorrectTypeImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/CorrectTypeImplicitReceiver.kt");
+            }
+
+            @TestMetadata("MultipleImplicitReceivers.kt")
+            public void testMultipleImplicitReceivers() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/MultipleImplicitReceivers.kt");
+            }
+
+            @TestMetadata("ObjectExplicitReceiver.kt")
+            public void testObjectExplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectExplicitReceiver.kt");
+            }
+
+            @TestMetadata("ObjectImplicitReceiver.kt")
+            public void testObjectImplicitReceiver() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/ObjectImplicitReceiver.kt");
+            }
+
+            @TestMetadata("OverridenExtensionsInObject.kt")
+            public void testOverridenExtensionsInObject() throws Exception {
+                runTest("idea/idea-completion/testData/basic/common/extensionMethodInObject/OverridenExtensionsInObject.kt");
+            }
+        }
+
         @TestMetadata("idea/idea-completion/testData/basic/common/extensions")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/handlers/BasicCompletionHandlerTestGenerated.java

@@ -343,6 +343,59 @@ public class BasicCompletionHandlerTestGenerated extends AbstractBasicCompletion
         }
     }
 
+    @TestMetadata("idea/idea-completion/testData/handlers/basic/extensionMethodInObject")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class ExtensionMethodInObject extends AbstractBasicCompletionHandlerTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInExtensionMethodInObject() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/idea-completion/testData/handlers/basic/extensionMethodInObject"), Pattern.compile("^([^.]+)\\.kt$"), TargetBackend.ANY, true);
+        }
+
+        @TestMetadata("CompanionObjectInSameFileExplicitReceiver.kt")
+        public void testCompanionObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("CompanionObjectInSameFileImplicitReceiver.kt")
+        public void testCompanionObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedCompanionObjectInSameFileExplicitReceiver.kt")
+        public void testNestedCompanionObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedCompanionObjectInSameFileImplicitReceiver.kt")
+        public void testNestedCompanionObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedObjectInSameFileExplicitReceiver.kt")
+        public void testNestedObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedObjectInSameFileImplicitReceiver.kt")
+        public void testNestedObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("ObjectInSameFileExplicitReceiver.kt")
+        public void testObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("ObjectInSameFileImplicitReceiver.kt")
+        public void testObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileImplicitReceiver.kt");
+        }
+    }
+
     @TestMetadata("idea/idea-completion/testData/handlers/basic/highOrderFunctions")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)

idea/performanceTests/org/jetbrains/kotlin/idea/perf/PerformanceBasicCompletionHandlerTestGenerated.java

@@ -343,6 +343,59 @@ public class PerformanceBasicCompletionHandlerTestGenerated extends AbstractPerf
         }
     }
 
+    @TestMetadata("idea/idea-completion/testData/handlers/basic/extensionMethodInObject")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class ExtensionMethodInObject extends AbstractPerformanceBasicCompletionHandlerTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doPerfTest, TargetBackend.ANY, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInExtensionMethodInObject() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/idea-completion/testData/handlers/basic/extensionMethodInObject"), Pattern.compile("^([^.]+)\\.kt$"), TargetBackend.ANY, true);
+        }
+
+        @TestMetadata("CompanionObjectInSameFileExplicitReceiver.kt")
+        public void testCompanionObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("CompanionObjectInSameFileImplicitReceiver.kt")
+        public void testCompanionObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/CompanionObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedCompanionObjectInSameFileExplicitReceiver.kt")
+        public void testNestedCompanionObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedCompanionObjectInSameFileImplicitReceiver.kt")
+        public void testNestedCompanionObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedCompanionObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedObjectInSameFileExplicitReceiver.kt")
+        public void testNestedObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("NestedObjectInSameFileImplicitReceiver.kt")
+        public void testNestedObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/NestedObjectInSameFileImplicitReceiver.kt");
+        }
+
+        @TestMetadata("ObjectInSameFileExplicitReceiver.kt")
+        public void testObjectInSameFileExplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileExplicitReceiver.kt");
+        }
+
+        @TestMetadata("ObjectInSameFileImplicitReceiver.kt")
+        public void testObjectInSameFileImplicitReceiver() throws Exception {
+            runTest("idea/idea-completion/testData/handlers/basic/extensionMethodInObject/ObjectInSameFileImplicitReceiver.kt");
+        }
+    }
+
     @TestMetadata("idea/idea-completion/testData/handlers/basic/highOrderFunctions")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)