Consider property external if all accessors are external #KT-13997 Fixed

compiler/testData/diagnostics/tests/ExternalAccessors.kt

@@ -0,0 +1,19 @@
+// See KT-13997
+
+class Foo {
+    var bar: Int // Ok
+        external get
+        external set
+}
+
+class Bar {
+    val foo: Int // Ok
+        external get
+
+    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>var baz: Int<!>
+        external get
+
+    <!MUST_BE_INITIALIZED_OR_BE_ABSTRACT!>var gav: Int<!>
+        external set
+}
+

compiler/testData/diagnostics/tests/ExternalAccessors.txt

@@ -0,0 +1,19 @@
+package
+
+public final class Bar {
+    public constructor Bar()
+    public final var baz: kotlin.Int
+    public final val foo: kotlin.Int
+    public final var gav: kotlin.Int
+    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
+}
+
+public final class Foo {
+    public constructor Foo()
+    public final var bar: kotlin.Int
+    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

@@ -254,6 +254,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("ExternalAccessors.kt")
+        public void testExternalAccessors() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/ExternalAccessors.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("ExternalAndAbstract.kt")
         public void testExternalAndAbstract() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");

core/descriptors/src/org/jetbrains/kotlin/resolve/DescriptorUtils.kt

@@ -422,6 +422,11 @@ fun MemberDescriptor.isEffectivelyExternal(): Boolean {
         if (variableDescriptor.isEffectivelyExternal()) return true
     }
 
+    if (this is PropertyDescriptor) {
+        if (getter?.isExternal == true &&
+            (!isVar || setter?.isExternal == true)) return true
+    }
+
     val containingClass = getContainingClass(this)
     return containingClass != null && containingClass.isEffectivelyExternal()
 }