Added diagnostic error when in function declaration name was omitted

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -333,6 +333,8 @@ public interface Errors {
     DiagnosticFactory1<JetFunction, SimpleFunctionDescriptor> NON_MEMBER_FUNCTION_NO_BODY =
             DiagnosticFactory1.create(ERROR, DECLARATION_SIGNATURE);
 
+    DiagnosticFactory0<JetFunction> FUNCTION_DECLARATION_WITH_NO_NAME = DiagnosticFactory0.create(ERROR, DECLARATION_SIGNATURE);
+
     DiagnosticFactory0<JetParameter> VALUE_PARAMETER_WITH_NO_TYPE_ANNOTATION = DiagnosticFactory0.create(ERROR);
 
     DiagnosticFactory0<JetNamedFunction> NO_TAIL_CALLS_FOUND = DiagnosticFactory0.create(WARNING, DECLARATION_SIGNATURE);

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/PositioningStrategies.kt

@@ -32,7 +32,9 @@ public object PositioningStrategies {
     private open class DeclarationHeader<T : JetDeclaration> : PositioningStrategy<T>() {
         override fun isValid(element: T): Boolean {
             if (element is JetNamedDeclaration &&
-                (element !is JetObjectDeclaration && element !is JetSecondaryConstructor)
+                element !is JetObjectDeclaration &&
+                element !is JetSecondaryConstructor &&
+                element !is JetNamedFunction
             ) {
                 if (element.getNameIdentifier() == null) {
                     return false
@@ -103,6 +105,9 @@ public object PositioningStrategies {
                 }
                 return markElement(nameIdentifier)
             }
+            if (element is JetNamedFunction) {
+                return DECLARATION_SIGNATURE.mark(element)
+            }
             return DEFAULT.mark(element)
         }
     }

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -224,6 +224,7 @@ public class DefaultErrorMessages {
         MAP.put(FINAL_FUNCTION_WITH_NO_BODY, "Function ''{0}'' without body cannot be final", NAME);
 
         MAP.put(NON_MEMBER_FUNCTION_NO_BODY, "Function ''{0}'' must have a body", NAME);
+        MAP.put(FUNCTION_DECLARATION_WITH_NO_NAME, "Function declaration must have a name");
         MAP.put(NON_FINAL_MEMBER_IN_FINAL_CLASS, "\"open\" has no effect in a final class");
 
         MAP.put(PUBLIC_MEMBER_SHOULD_SPECIFY_TYPE, "Public or protected member should have specified type");

compiler/frontend/src/org/jetbrains/kotlin/resolve/DescriptorResolver.java

@@ -237,7 +237,19 @@ public class DescriptorResolver {
             @NotNull DataFlowInfo dataFlowInfo
     ) {
         return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
-                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace));
+                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace), false);
+    }
+
+    @NotNull
+    public SimpleFunctionDescriptor resolveAnonymousFunctionDescriptor(
+            @NotNull DeclarationDescriptor containingDescriptor,
+            @NotNull JetScope scope,
+            @NotNull JetNamedFunction function,
+            @NotNull BindingTrace trace,
+            @NotNull DataFlowInfo dataFlowInfo
+    ) {
+        return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
+                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace), true);
     }
 
     @NotNull
@@ -249,7 +261,7 @@ public class DescriptorResolver {
             @NotNull DataFlowInfo dataFlowInfo
     ) {
        return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
-                                        annotationResolver.resolveAnnotationsWithoutArguments(scope, function.getModifierList(), trace));
+                                        annotationResolver.resolveAnnotationsWithoutArguments(scope, function.getModifierList(), trace), false);
     }
 
     @NotNull
@@ -259,12 +271,17 @@ public class DescriptorResolver {
             @NotNull final JetNamedFunction function,
             @NotNull final BindingTrace trace,
             @NotNull final DataFlowInfo dataFlowInfo,
-            @NotNull Annotations annotations
+            @NotNull Annotations annotations,
+            boolean nameCanBeOmitted
     ) {
+        if (!nameCanBeOmitted && function.getName() == null) {
+            trace.report(FUNCTION_DECLARATION_WITH_NO_NAME.on(function));
+        }
+
         final SimpleFunctionDescriptorImpl functionDescriptor = SimpleFunctionDescriptorImpl.create(
                 containingDescriptor,
                 annotations,
-                JetPsiUtil.safeName(function.getName()),
+                function.getNameAsSafeName(),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 toSourceElement(function)
         );

compiler/testData/diagnostics/tests/declarationChecks/FunctionWithMissingNames.kt

@@ -0,0 +1,25 @@
+annotation class a
+trait A
+trait B
+
+<!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>fun ()<!> {}
+<!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>fun A.()<!> {}
+
+<!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>a fun ()<!> {}
+<!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>fun [a] A.()<!> {}
+
+class Outer {
+    <!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>fun ()<!> {}
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun B.()<!> {}
+
+    <!FUNCTION_DECLARATION_WITH_NO_NAME, CONFLICTING_OVERLOADS!>a fun ()<!> {}
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun [a] A.()<!> {}
+}
+
+fun outerFun() {
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {}
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun B.()<!> {}
+
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>[a] fun ()<!> {}
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun [a] A.()<!> {}
+}

compiler/testData/diagnostics/tests/declarationChecks/FunctionWithMissingNames.txt

@@ -0,0 +1,37 @@
+package
+
+a() internal fun <no name provided>(): kotlin.Unit
+internal fun <no name provided>(): kotlin.Unit
+internal fun outerFun(): kotlin.Unit
+internal fun A.<no name provided>(): kotlin.Unit
+internal fun A.<no name provided>(): kotlin.Unit
+
+internal trait 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
+}
+
+internal trait B {
+    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
+}
+
+internal final class Outer {
+    public constructor Outer()
+    a() internal final fun <no name provided>(): kotlin.Unit
+    internal final fun <no name provided>(): kotlin.Unit
+    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
+    internal final fun A.<no name provided>(): kotlin.Unit
+    internal final fun B.<no name provided>(): kotlin.Unit
+}
+
+internal 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/duplicateJvmSignature/missingNames.kt

@@ -1,4 +1,8 @@
-fun<!SYNTAX!><!> () {
+<!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
+
+}
+
+<!FUNCTION_DECLARATION_WITH_NO_NAME!>fun Outer.()<!> {
 
 }
 
@@ -25,7 +29,7 @@ annotation class<!SYNTAX!><!> <!ANNOTATION_CLASS_WITH_BODY!>{
 }<!>
 
 class Outer {
-    fun<!SYNTAX!><!> () {
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
 
     }
 
@@ -50,4 +54,14 @@ class Outer {
     <!REDECLARATION!>annotation class<!SYNTAX!><!> <!ANNOTATION_CLASS_WITH_BODY!>{
 
     }<!><!>
-}
+}
+
+fun outerFun() {
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
+
+    }
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
+
+    }
+}
+

compiler/testData/diagnostics/tests/duplicateJvmSignature/missingNames.txt

@@ -2,6 +2,8 @@ package
 
 internal val <no name provided>: kotlin.Int = 1
 internal fun <no name provided>(): kotlin.Unit
+internal fun outerFun(): kotlin.Unit
+internal fun Outer.<no name provided>(): kotlin.Unit
 
 internal final class <no name provided> {
     internal constructor <no name provided>()

compiler/testData/diagnostics/tests/recovery/namelessInJava.kt

@@ -12,6 +12,6 @@ public class Nameless {
 import p.*
 
 class K : <!INVISIBLE_MEMBER!>Nameless<!>() {
-    fun<!SYNTAX!><!> () {}
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {}
     val<!SYNTAX!><!> : Int = 1
-}
+}

compiler/testData/diagnostics/tests/recovery/namelessMembers.kt

@@ -1,7 +1,7 @@
 // !DIAGNOSTICS: -REDECLARATION
 
 class C {
-    fun<!SYNTAX!><!> () {
+    <!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
 
     }
 

compiler/testData/diagnostics/tests/recovery/namelessToplevelDeclarations.kt

@@ -2,7 +2,7 @@
 
 package<!SYNTAX!><!>
 
-fun<!SYNTAX!><!> () {
+<!FUNCTION_DECLARATION_WITH_NO_NAME!>fun ()<!> {
 
 }
 

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

@@ -2965,6 +2965,12 @@ public class JetDiagnosticsTestGenerated extends AbstractJetDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("FunctionWithMissingNames.kt")
+            public void testFunctionWithMissingNames() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/declarationChecks/FunctionWithMissingNames.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("illegalModifiersOnClass.kt")
             public void testIllegalModifiersOnClass() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/declarationChecks/illegalModifiersOnClass.kt");

idea/testData/checker/recovery/namelessMembers.kt

@@ -1,5 +1,5 @@
 class C {
-    fun<error> </error>() {
+    <error>fun ()</error> {
 
     }
 

idea/testData/checker/recovery/namelessToplevelDeclarations.kt

@@ -1,6 +1,6 @@
 package<EOLError></EOLError>
 
-fun<error> </error>() {
+<error>fun ()</error> {
 
 }
 

idea/testData/intentions/declarations/convertMemberToExtension/funcitonNoName.kt

@@ -1,3 +1,4 @@
+// ERROR: Function declaration must have a name
 class Owner {
   fun <caret>() {}
 }

idea/testData/intentions/declarations/convertMemberToExtension/funcitonNoName.kt.after

@@ -1,3 +1,4 @@
+// ERROR: Function declaration must have a name
 class Owner {
 }
 

idea/testData/quickfix/autoImports/beforeNamelessFunction.kt

@@ -1,5 +1,6 @@
 // "class com.intellij.codeInsight.daemon.impl.quickfix.ImportClassFixBase" "false"
 // ERROR: Unresolved reference: TTTTT
+// ERROR: Function declaration must have a name
 
 fun () {
     val tttt : TTTTT = null

idea/testData/quickfix/typeMismatch/afterChangeReturnTypeWhenFunctionNameIsMissing.kt

@@ -1,4 +1,5 @@
 // "Remove explicitly specified function return type" "true"
+// ERROR: Function declaration must have a name
 fun () {
     return<caret>
 }

idea/testData/quickfix/typeMismatch/beforeChangeReturnTypeWhenFunctionNameIsMissing.kt

@@ -1,4 +1,5 @@
 // "Remove explicitly specified function return type" "true"
+// ERROR: Function declaration must have a name
 fun (): Int {
     return<caret>
 }