Don't issue a warning about expect/actual in the same module for incompatible expect/actual pairs

^KT-57067 Fixed
Review: https://jetbrains.team/p/kt/reviews/9123

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java

@@ -22062,6 +22062,12 @@ public class DiagnosisCompilerTestFE10TestdataTestGenerated extends AbstractDiag
                         runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModule.kt");
                     }
 
+                    @Test
+                    @TestMetadata("expectAndActualInTheSameModuleIncompatibilities.kt")
+                    public void testExpectAndActualInTheSameModuleIncompatibilities() throws Exception {
+                        runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.kt");
+                    }
+
                     @Test
                     @TestMetadata("intermediateWithActualAndExpect.kt")
                     public void testIntermediateWithActualAndExpect() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java

@@ -22062,6 +22062,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
                         runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModule.kt");
                     }
 
+                    @Test
+                    @TestMetadata("expectAndActualInTheSameModuleIncompatibilities.kt")
+                    public void testExpectAndActualInTheSameModuleIncompatibilities() throws Exception {
+                        runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.kt");
+                    }
+
                     @Test
                     @TestMetadata("intermediateWithActualAndExpect.kt")
                     public void testIntermediateWithActualAndExpect() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java

@@ -22068,6 +22068,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
                         runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModule.kt");
                     }
 
+                    @Test
+                    @TestMetadata("expectAndActualInTheSameModuleIncompatibilities.kt")
+                    public void testExpectAndActualInTheSameModuleIncompatibilities() throws Exception {
+                        runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.kt");
+                    }
+
                     @Test
                     @TestMetadata("intermediateWithActualAndExpect.kt")
                     public void testIntermediateWithActualAndExpect() throws Exception {

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/ExpectActualInTheSameModuleChecker.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.platform.isCommon
 import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.psi.KtNamedDeclaration
+import org.jetbrains.kotlin.resolve.checkers.ExpectedActualDeclarationChecker.Companion.isCompatibleOrWeakCompatible
 import org.jetbrains.kotlin.resolve.descriptorUtil.module
 import org.jetbrains.kotlin.resolve.multiplatform.ExpectedActualResolver
 import org.jetbrains.kotlin.resolve.multiplatform.isCommonSource
@@ -27,7 +28,9 @@ object ExpectActualInTheSameModuleChecker : DeclarationChecker {
         // Only look for top level actual members; class members will be handled as a part of that expected class
         if (descriptor.containingDeclaration !is PackageFragmentDescriptor) return
         val module = descriptor.module
-        val actuals = ExpectedActualResolver.findActualForExpected(descriptor, module)?.flatMap { it.value }
+        val actuals = ExpectedActualResolver.findActualForExpected(descriptor, module)
+            ?.filter { (compatibility, _) -> compatibility.isCompatibleOrWeakCompatible() }
+            ?.flatMap { (_, members) -> members }
             ?.takeIf(List<MemberDescriptor>::isNotEmpty) ?: return
 
         // There are 4 cases:

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/ExpectedActualDeclarationChecker.kt

@@ -329,10 +329,6 @@ class ExpectedActualDeclarationChecker(
         }
     }
 
-    private fun ExpectActualCompatibility<MemberDescriptor>.isCompatibleOrWeakCompatible() =
-        this is Compatible ||
-                this is Incompatible && kind == IncompatibilityKind.WEAK
-
     // we don't require `actual` modifier on
     //  - annotation constructors, because annotation classes can only have one constructor
     //  - inline class primary constructors, because inline class must have primary constructor
@@ -399,6 +395,10 @@ class ExpectedActualDeclarationChecker(
     companion object {
         fun Map<out ExpectActualCompatibility<MemberDescriptor>, Collection<MemberDescriptor>>.allStrongIncompatibilities(): Boolean =
             this.keys.all { it is Incompatible && it.kind == IncompatibilityKind.STRONG }
+
+        internal fun ExpectActualCompatibility<MemberDescriptor>.isCompatibleOrWeakCompatible() =
+            this is Compatible ||
+                    this is Incompatible && kind == IncompatibilityKind.WEAK
     }
 }
 

compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.fir.kt

@@ -0,0 +1,31 @@
+// MODULE: common
+// TARGET_PLATFORM: Common
+
+expect fun parameterCount()
+fun parameterCount(p: String) {}
+
+expect fun parameterCount2()
+<!ACTUAL_WITHOUT_EXPECT!>actual fun parameterCount2(p: String) {}<!>
+
+expect fun callableKind(): Int
+val callableKind: Int = 1
+
+expect fun <T> typeParameterCount()
+fun typeParameterCount() {}
+
+expect enum class EnumEntries {
+    ONE, TWO;
+}
+<!ACTUAL_WITHOUT_EXPECT!>actual enum class EnumEntries {
+    ONE;
+}<!>
+
+expect fun vararg(bar: Int)
+fun vararg(vararg bar: Int) = Unit
+
+// MODULE: main()()(common)
+
+actual fun parameterCount() {}
+actual fun <T> typeParameterCount() {}
+actual fun callableKind(): Int = 1
+actual fun vararg(bar: Int) = Unit

compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.kt

@@ -0,0 +1,31 @@
+// MODULE: common
+// TARGET_PLATFORM: Common
+
+expect fun parameterCount()
+fun parameterCount(p: String) {}
+
+expect fun parameterCount2()
+actual fun parameterCount2(p: String) {}
+
+expect fun callableKind(): Int
+val callableKind: Int = 1
+
+expect fun <T> typeParameterCount()
+fun typeParameterCount() {}
+
+expect <!EXPECT_AND_ACTUAL_IN_THE_SAME_MODULE!>enum class EnumEntries<!> {
+    ONE, TWO;
+}
+actual <!EXPECT_AND_ACTUAL_IN_THE_SAME_MODULE!>enum class EnumEntries<!> {
+    ONE;
+}
+
+expect fun vararg(bar: Int)
+fun vararg(vararg bar: Int) = Unit
+
+// MODULE: main()()(common)
+
+actual fun parameterCount() {}
+actual fun <T> typeParameterCount() {}
+actual fun callableKind(): Int = 1
+actual fun vararg(bar: Int) = Unit

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -22068,6 +22068,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                         runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModule.kt");
                     }
 
+                    @Test
+                    @TestMetadata("expectAndActualInTheSameModuleIncompatibilities.kt")
+                    public void testExpectAndActualInTheSameModuleIncompatibilities() throws Exception {
+                        runTest("compiler/testData/diagnostics/tests/multiplatform/hmpp/multiplatformCompositeAnalysis/expectAndActualInTheSameModuleIncompatibilities.kt");
+                    }
+
                     @Test
                     @TestMetadata("intermediateWithActualAndExpect.kt")
                     public void testIntermediateWithActualAndExpect() throws Exception {