Fix typechecker when initializer of destructuring declaration is unresolved or missing

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/DestructuringDeclarationResolver.kt

@@ -42,14 +42,14 @@ class DestructuringDeclarationResolver(
     fun defineLocalVariablesFromMultiDeclaration(
             writableScope: LexicalWritableScope,
             destructuringDeclaration: KtDestructuringDeclaration,
-            receiver: ReceiverValue,
+            receiver: ReceiverValue?,
-            reportErrorsOn: KtExpression,
+            initializer: KtExpression?,
             context: ExpressionTypingContext
     ) {
         for ((componentIndex, entry) in destructuringDeclaration.entries.withIndex()) {
             val componentName = createComponentName(componentIndex + 1)
 
-            val componentType = resolveComponentFunctionAndGetType(componentName, context, entry, receiver, reportErrorsOn)
+            val componentType = resolveComponentFunctionAndGetType(componentName, context, entry, receiver, initializer)
             val variableDescriptor = localVariableResolver.resolveLocalVariableDescriptorWithType(writableScope, entry, componentType, context.trace)
 
             ExpressionTypingUtils.checkVariableShadowing(writableScope, context.trace, variableDescriptor)
@@ -62,15 +62,17 @@ class DestructuringDeclarationResolver(
             componentName: Name,
             context: ExpressionTypingContext,
             entry: KtDestructuringDeclarationEntry,
-            receiver: ReceiverValue,
+            receiver: ReceiverValue?,
-            reportErrorsOn: KtExpression
+            initializer: KtExpression?
     ): KotlinType {
         fun errorType() = ErrorUtils.createErrorType("$componentName() return type")
 
+        if (receiver == null || initializer == null) return errorType()
+
         val expectedType = getExpectedTypeForComponent(context, entry)
         val results = fakeCallResolver.resolveFakeCall(
                 context.replaceExpectedType(expectedType), receiver, componentName,
-                entry, reportErrorsOn, FakeCallKind.COMPONENT
+                entry, initializer, FakeCallKind.COMPONENT
         )
 
         if (!results.isSuccess) {
@@ -85,7 +87,7 @@ class DestructuringDeclarationResolver(
         val functionReturnType = functionDescriptor.returnType
         if (functionReturnType != null && !TypeUtils.noExpectedType(expectedType)
             && !KotlinTypeChecker.DEFAULT.isSubtypeOf(functionReturnType, expectedType) ) {
-            context.trace.report(Errors.COMPONENT_FUNCTION_RETURN_TYPE_MISMATCH.on(reportErrorsOn, componentName, functionReturnType, expectedType))
+            context.trace.report(Errors.COMPONENT_FUNCTION_RETURN_TYPE_MISMATCH.on(initializer, componentName, functionReturnType, expectedType))
         }
         return functionReturnType ?: errorType()
     }

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/ExpressionTypingVisitorForStatements.java

@@ -117,19 +117,23 @@ public class ExpressionTypingVisitorForStatements extends ExpressionTypingVisito
         KtExpression initializer = multiDeclaration.getInitializer();
         if (initializer == null) {
             context.trace.report(INITIALIZER_REQUIRED_FOR_DESTRUCTURING_DECLARATION.on(multiDeclaration));
-            return TypeInfoFactoryKt.noTypeInfo(context);
-        }
-        ExpressionReceiver expressionReceiver = ExpressionTypingUtils.getExpressionReceiver(
-                facade, initializer, context.replaceExpectedType(NO_EXPECTED_TYPE).replaceContextDependency(INDEPENDENT));
-        KotlinTypeInfo typeInfo = facade.getTypeInfo(initializer, context);
-        if (expressionReceiver == null) {
-            return TypeInfoFactoryKt.noTypeInfo(context);
         }
+
+        ExpressionReceiver expressionReceiver = initializer != null ? ExpressionTypingUtils.getExpressionReceiver(
+                facade, initializer, context.replaceExpectedType(NO_EXPECTED_TYPE).replaceContextDependency(INDEPENDENT)) : null;
+
         components.destructuringDeclarationResolver
                 .defineLocalVariablesFromMultiDeclaration(scope, multiDeclaration, expressionReceiver, initializer, context);
         components.modifiersChecker.withTrace(context.trace).checkModifiersForDestructuringDeclaration(multiDeclaration);
         components.identifierChecker.checkDeclaration(multiDeclaration, context.trace);
-        return typeInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(multiDeclaration, context));
+
+        if (expressionReceiver == null) {
+            return TypeInfoFactoryKt.noTypeInfo(context);
+        }
+        else {
+            return facade.getTypeInfo(initializer, context)
+                    .replaceType(components.dataFlowAnalyzer.checkStatementType(multiDeclaration, context));
+        }
     }
 
     @Override

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationAssignedUnresolved.kt

@@ -0,0 +1,11 @@
+fun useDeclaredVariables() {
+    val (a, b) = <!UNRESOLVED_REFERENCE!>unresolved<!>
+    <!UNUSED_EXPRESSION, DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>a<!>
+    <!UNUSED_EXPRESSION, DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>b<!>
+}
+
+fun checkersShouldRun() {
+    val (@A <!UNUSED_VARIABLE!>a<!>, <!UNDERSCORE_IS_RESERVED, UNUSED_VARIABLE!>_<!>) = <!UNRESOLVED_REFERENCE!>unresolved<!>
+}
+
+annotation class A

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationAssignedUnresolved.txt

@@ -0,0 +1,11 @@
+package
+
+public fun checkersShouldRun(): kotlin.Unit
+public fun useDeclaredVariables(): kotlin.Unit
+
+public final annotation class A : kotlin.Annotation {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationMissingInitializer.kt

@@ -0,0 +1,11 @@
+fun useDeclaredVariables() {
+    <!INITIALIZER_REQUIRED_FOR_DESTRUCTURING_DECLARATION!>val (a, b)<!>
+    <!UNUSED_EXPRESSION, DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>a<!>
+    <!UNUSED_EXPRESSION, DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>b<!>
+}
+
+fun checkersShouldRun() {
+    <!INITIALIZER_REQUIRED_FOR_DESTRUCTURING_DECLARATION!>val (@A <!UNUSED_VARIABLE!>a<!>, <!UNDERSCORE_IS_RESERVED, UNUSED_VARIABLE!>_<!>)<!>
+}
+
+annotation class A

compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationMissingInitializer.txt

@@ -0,0 +1,11 @@
+package
+
+public fun checkersShouldRun(): kotlin.Unit
+public fun useDeclaredVariables(): kotlin.Unit
+
+public final annotation class A : kotlin.Annotation {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -4463,6 +4463,18 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                     doTest(fileName);
                 }
 
+                @TestMetadata("multiDeclarationAssignedUnresolved.kt")
+                public void testMultiDeclarationAssignedUnresolved() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationAssignedUnresolved.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("multiDeclarationMissingInitializer.kt")
+                public void testMultiDeclarationMissingInitializer() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/multiDeclarationMissingInitializer.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("RedeclarationInForLoop.kt")
                 public void testRedeclarationInForLoop() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/declarationChecks/multiDeclarations/RedeclarationInForLoop.kt");