Allow to use emptyArray in annotation as argument

#KT-14236 Fixed

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -56,7 +56,8 @@ public class CompileTimeConstantUtils {
             "kotlin.charArrayOf",
             "kotlin.shortArrayOf",
             "kotlin.byteArrayOf",
-            "kotlin.booleanArrayOf"
+            "kotlin.booleanArrayOf",
+            "kotlin.emptyArray"
     );
 
     public static void checkConstructorParametersType(@NotNull List<KtParameter> parameters, @NotNull BindingTrace trace) {
@@ -110,7 +111,7 @@ public class CompileTimeConstantUtils {
         return false;
     }
 
-    public static boolean isArrayMethodCall(@NotNull ResolvedCall<?> resolvedCall) {
+    public static boolean isArrayFunctionCall(@NotNull ResolvedCall<?> resolvedCall) {
         return ARRAY_CALL_NAMES.contains(DescriptorUtils.getFqName(resolvedCall.getCandidateDescriptor()).asString());
     }
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/constants/evaluate/ConstantExpressionEvaluator.kt

@@ -166,23 +166,24 @@ class ConstantExpressionEvaluator(
             trace: BindingTrace
     ): Pair<List<KtExpression>, KotlinType?>? {
         val resolvedCall = expression.getResolvedCall(trace.bindingContext)
-        if (resolvedCall == null || !CompileTimeConstantUtils.isArrayMethodCall(resolvedCall)) {
+        if (resolvedCall == null || !CompileTimeConstantUtils.isArrayFunctionCall(resolvedCall)) {
             return null
         }
 
-        val argumentEntry = resolvedCall.valueArguments.entries.single()
-
-        val elementType = argumentEntry.key.varargElementType ?: return null
+        val returnType = resolvedCall.resultingDescriptor.returnType ?: return null
+        val componentType = builtIns.getArrayElementType(returnType)
 
         val result = arrayListOf<KtExpression>()
-        for (valueArgument in argumentEntry.value.arguments) {
-            val valueArgumentExpression = valueArgument.getArgumentExpression()
-            if (valueArgumentExpression != null) {
-                result.add(valueArgumentExpression)
+        for ((_, resolvedValueArgument) in resolvedCall.valueArguments) {
+            for (valueArgument in resolvedValueArgument.arguments) {
+                val valueArgumentExpression = valueArgument.getArgumentExpression()
+                if (valueArgumentExpression != null) {
+                    result.add(valueArgumentExpression)
+                }
             }
         }
 
-        return Pair<List<KtExpression>, KotlinType>(result, elementType)
+        return Pair<List<KtExpression>, KotlinType>(result, componentType)
     }
 
     private fun hasSpread(argument: ResolvedValueArgument): Boolean {
@@ -646,13 +647,14 @@ private class ConstantExpressionEvaluatorVisitor(
 
         val resultingDescriptor = call.resultingDescriptor
 
-        // arrayOf()
-        if (CompileTimeConstantUtils.isArrayMethodCall(call)) {
-            val varargType = resultingDescriptor.valueParameters.first().varargElementType!!
+        // arrayOf() or emptyArray()
+        if (CompileTimeConstantUtils.isArrayFunctionCall(call)) {
+            val returnType = resultingDescriptor.returnType ?: return null
+            val componentType = constantExpressionEvaluator.builtIns.getArrayElementType(returnType)
 
-            val arguments = call.valueArguments.values.flatMap { resolveArguments(it.arguments, varargType) }
+            val arguments = call.valueArguments.values.flatMap { resolveArguments(it.arguments, componentType) }
 
-            return factory.createArrayValue(arguments.map { it.toConstantValue(varargType) }, resultingDescriptor.returnType!!).
+            return factory.createArrayValue(arguments.map { it.toConstantValue(componentType) }, resultingDescriptor.returnType!!).
                     wrap(
                             usesVariableAsConstant = arguments.any { it.usesVariableAsConstant },
                             usesNonConstValAsConstant = arguments.any { it.usesNonConstValAsConstant }

compiler/testData/codegen/box/defaultArguments/constructor/annotationWithEmptyArray.kt

@@ -0,0 +1,8 @@
+annotation class Anno(val x: Array<String> = emptyArray())
+
+@Anno fun test1() = 1
+@Anno(arrayOf("K")) fun test2() = 2
+
+fun box(): String {
+    return if (test1() + test2() == 3) "OK" else "Fail"
+}

compiler/testData/codegen/light-analysis/defaultArguments/constructor/annotationWithEmptyArray.txt

@@ -0,0 +1,12 @@
+@java.lang.annotation.Retention
+@kotlin.Metadata
+public annotation class Anno {
+    public abstract method x(): java.lang.String[]
+}
+
+@kotlin.Metadata
+public final class AnnotationWithEmptyArrayKt {
+    public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
+    public final static @Anno method test1(): int
+    public final static @Anno method test2(): int
+}

compiler/testData/diagnostics/testsWithStdLib/annotations/annotationParameterMustBeConstant/simple.kt

@@ -19,6 +19,7 @@ val i2 = foo()
 
 fun foo(): Int = 1
 
+@AnnSA(emptyArray())
 class MyClass {
     val i = 1
 }

compiler/testData/diagnostics/testsWithStdLib/annotations/annotationParameterMustBeConstant/simple.txt

@@ -37,7 +37,7 @@ public final annotation class AnnSA : kotlin.Annotation {
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 
-public final class MyClass {
+@AnnSA(sa = {}) public final class MyClass {
     public constructor MyClass()
     public final val i: kotlin.Int = 1
     public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean

compiler/tests-ir-jvm/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -5845,6 +5845,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 doTest(fileName);
             }
 
+            @TestMetadata("annotationWithEmptyArray.kt")
+            public void testAnnotationWithEmptyArray() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/annotationWithEmptyArray.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("checkIfConstructorIsSynthetic.kt")
             public void testCheckIfConstructorIsSynthetic() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/checkIfConstructorIsSynthetic.kt");

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -5845,6 +5845,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("annotationWithEmptyArray.kt")
+            public void testAnnotationWithEmptyArray() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/annotationWithEmptyArray.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("checkIfConstructorIsSynthetic.kt")
             public void testCheckIfConstructorIsSynthetic() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/checkIfConstructorIsSynthetic.kt");

idea/src/org/jetbrains/kotlin/idea/codeInliner/CodeInliner.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -500,7 +500,7 @@ class CodeInliner<TCallElement : KtElement>(
                 val argumentExpression = argument.getArgumentExpression() ?: return@forEachDescendantOfType
                 val resolvedCall = argumentExpression.getResolvedCall(argumentExpression.analyze(BodyResolveMode.PARTIAL)) ?: return@forEachDescendantOfType
                 val callExpression = resolvedCall.call.callElement as? KtCallExpression ?: return@forEachDescendantOfType
-                if (CompileTimeConstantUtils.isArrayMethodCall(resolvedCall)) {
+                if (CompileTimeConstantUtils.isArrayFunctionCall(resolvedCall)) {
                     argumentsToExpand.add(argument to callExpression.valueArguments)
                 }
             }

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -6614,6 +6614,12 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("annotationWithEmptyArray.kt")
+            public void testAnnotationWithEmptyArray() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/annotationWithEmptyArray.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("checkIfConstructorIsSynthetic.kt")
             public void testCheckIfConstructorIsSynthetic() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/defaultArguments/constructor/checkIfConstructorIsSynthetic.kt");