Introduce KotlinBuiltIns.isUnderKotlinPackage

Semantics is the same as in the former
FunctionDescriptor.hasSubpackageOfKotlin, but it doesn't compute the FQ
name of the descriptor

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/OperatorCallChecker.kt

@@ -24,7 +24,6 @@ import org.jetbrains.kotlin.config.LanguageVersionSettings
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.diagnostics.DiagnosticSink
 import org.jetbrains.kotlin.diagnostics.Errors
-import org.jetbrains.kotlin.name.isSubpackageOf
 import org.jetbrains.kotlin.psi.Call
 import org.jetbrains.kotlin.psi.KtArrayAccessExpression
 import org.jetbrains.kotlin.psi.KtDestructuringDeclarationEntry
@@ -34,7 +33,6 @@ import org.jetbrains.kotlin.resolve.calls.callResolverUtil.isConventionCall
 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.resolve.calls.model.VariableAsFunctionResolvedCall
 import org.jetbrains.kotlin.resolve.calls.tasks.isDynamic
-import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameOrNull
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
 import org.jetbrains.kotlin.types.ErrorUtils
 import org.jetbrains.kotlin.types.expressions.OperatorConventions
@@ -105,22 +103,17 @@ fun FunctionDescriptor.isOperatorMod(): Boolean {
     return this.isOperator && name in OperatorConventions.REM_TO_MOD_OPERATION_NAMES.values
 }
 
-// This is an alternate function to KotlinBuiltIns.isBuiltIn
-// It is safer as it produces stable results independent of target platform (Java/JS/Native)
-fun FunctionDescriptor.hasSubpackageOfKotlin(): Boolean {
-    val descriptorFqName = fqNameOrNull() ?: return false
-    return descriptorFqName.isSubpackageOf(KotlinBuiltIns.BUILT_INS_PACKAGE_FQ_NAME)
-}
-
 fun shouldWarnAboutDeprecatedModFromBuiltIns(languageVersionSettings: LanguageVersionSettings): Boolean {
     return languageVersionSettings.supportsFeature(LanguageFeature.OperatorRem) && languageVersionSettings.apiVersion >= ApiVersion.KOTLIN_1_1
 }
 
-private fun checkModConvention(descriptor: FunctionDescriptor, languageVersionSettings: LanguageVersionSettings,
-                               diagnosticHolder: DiagnosticSink, modifier: PsiElement) {
+private fun checkModConvention(
+        descriptor: FunctionDescriptor, languageVersionSettings: LanguageVersionSettings,
+        diagnosticHolder: DiagnosticSink, modifier: PsiElement
+) {
     if (!descriptor.isOperatorMod()) return
 
-    if (descriptor.hasSubpackageOfKotlin()) {
+    if (KotlinBuiltIns.isUnderKotlinPackage(descriptor)) {
         if (shouldWarnAboutDeprecatedModFromBuiltIns(languageVersionSettings)) {
             addWarningAboutDeprecatedMod(descriptor, diagnosticHolder, modifier)
         }
@@ -136,4 +129,3 @@ private fun addWarningAboutDeprecatedMod(descriptor: FunctionDescriptor, diagnos
     val newNameConvention = OperatorConventions.REM_TO_MOD_OPERATION_NAMES.inverse()[descriptor.name]
     diagnosticHolder.report(Errors.DEPRECATED_BINARY_MOD_AS_REM.on(reportOn, descriptor, newNameConvention!!.asString()))
 }
-

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

@@ -473,9 +473,7 @@ private class ConstantExpressionEvaluatorVisitor(
 
     private fun evaluateCall(callExpression: KtExpression, receiverExpression: KtExpression, expectedType: KotlinType?): CompileTimeConstant<*>? {
         val resolvedCall = callExpression.getResolvedCall(trace.bindingContext) ?: return null
-
-        val descriptorFqName = resolvedCall.resultingDescriptor.fqNameOrNull() ?: return null
-        if (!descriptorFqName.isSubpackageOf(KotlinBuiltIns.BUILT_INS_PACKAGE_FQ_NAME)) return null
+        if (!KotlinBuiltIns.isUnderKotlinPackage(resolvedCall.resultingDescriptor)) return null
 
         val resultingDescriptorName = resolvedCall.resultingDescriptor.name
 

compiler/frontend/src/org/jetbrains/kotlin/resolve/deprecationUtil.kt

@@ -30,7 +30,6 @@ import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.resolve.DeprecationLevelValue.*
 import org.jetbrains.kotlin.resolve.annotations.argumentValue
-import org.jetbrains.kotlin.resolve.calls.checkers.hasSubpackageOfKotlin
 import org.jetbrains.kotlin.resolve.calls.checkers.isOperatorMod
 import org.jetbrains.kotlin.resolve.calls.checkers.shouldWarnAboutDeprecatedModFromBuiltIns
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
@@ -190,7 +189,7 @@ private fun deprecationByOverridden(root: CallableMemberDescriptor, languageVers
 
 private fun DeclarationDescriptor.getOwnDeprecations(languageVersionSettings: LanguageVersionSettings): List<Deprecation> {
     // The problem is that declaration `mod` in built-ins has @Deprecated annotation but actually it was deprecated only in version 1.1
-    if (this is FunctionDescriptor && this.isOperatorMod() && this.hasSubpackageOfKotlin()) {
+    if (this is FunctionDescriptor && this.isOperatorMod() && KotlinBuiltIns.isUnderKotlinPackage(this)) {
         if (!shouldWarnAboutDeprecatedModFromBuiltIns(languageVersionSettings)) {
             return emptyList()
         }

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaClassDescriptor.kt

@@ -210,8 +210,8 @@ class LazyJavaClassDescriptor(
         }
 
         private fun getPurelyImplementedSupertype(): KotlinType? {
-            val annotatedPurelyImplementedFqName = getPurelyImplementsFqNameFromAnnotation()?.takeIf {
-                !it.isRoot && it.toUnsafe().startsWith(KotlinBuiltIns.BUILT_INS_PACKAGE_NAME)
+            val annotatedPurelyImplementedFqName = getPurelyImplementsFqNameFromAnnotation()?.takeIf { fqName ->
+                !fqName.isRoot && fqName.startsWith(KotlinBuiltIns.BUILT_INS_PACKAGE_NAME)
             }
 
             val purelyImplementedFqName =

core/descriptors/src/org/jetbrains/kotlin/builtins/KotlinBuiltIns.java

@@ -381,6 +381,20 @@ public abstract class KotlinBuiltIns {
         return DescriptorUtils.getParentOfType(descriptor, BuiltInsPackageFragment.class, false) != null;
     }
 
+    /**
+     * @return true if the containing package of the descriptor is "kotlin" or any subpackage of "kotlin"
+     */
+    public static boolean isUnderKotlinPackage(@NotNull DeclarationDescriptor descriptor) {
+        DeclarationDescriptor current = descriptor;
+        while (current != null) {
+            if (current instanceof PackageFragmentDescriptor) {
+                return ((PackageFragmentDescriptor) current).getFqName().startsWith(BUILT_INS_PACKAGE_NAME);
+            }
+            current = current.getContainingDeclaration();
+        }
+        return false;
+    }
+
     @NotNull
     public MemberScope getBuiltInsPackageScope() {
         return packageFragments.invoke().builtInsPackageFragment.getMemberScope();

core/descriptors/src/org/jetbrains/kotlin/name/FqName.java

@@ -98,6 +98,10 @@ public final class FqName {
         return fqName.pathSegments();
     }
 
+    public boolean startsWith(@NotNull Name segment) {
+        return fqName.startsWith(segment);
+    }
+
     @NotNull
     public static FqName topLevel(@NotNull Name shortName) {
         return new FqName(FqNameUnsafe.topLevel(shortName));