[FIR] KT-57568: Make K2 treat signed ints as more specific than unsigned

This is the way it works in K1.
See `OverloadingConflictResolver.kt:345`.

^KT-57568 Fixed

Merge-request: KT-MR-9395
Merged-by: Nikolay Lunyak <Nikolay.Lunyak@jetbrains.com>

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -35299,6 +35299,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
             KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/testsWithStdLib"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true, "native");
         }
 
+        @Test
+        @TestMetadata("ambiguityWithUnsignedSpecificity.kt")
+        public void testAmbiguityWithUnsignedSpecificity() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt");
+        }
+
         @Test
         @TestMetadata("ArrayOfNothing.kt")
         public void testArrayOfNothing() throws Exception {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -35299,6 +35299,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
             KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/testsWithStdLib"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true, "native");
         }
 
+        @Test
+        @TestMetadata("ambiguityWithUnsignedSpecificity.kt")
+        public void testAmbiguityWithUnsignedSpecificity() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt");
+        }
+
         @Test
         @TestMetadata("ArrayOfNothing.kt")
         public void testArrayOfNothing() throws Exception {

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

@@ -35299,6 +35299,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
             KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/testsWithStdLib"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
         }
 
+        @Test
+        @TestMetadata("ambiguityWithUnsignedSpecificity.kt")
+        public void testAmbiguityWithUnsignedSpecificity() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt");
+        }
+
         @Test
         @TestMetadata("ArrayOfNothing.kt")
         public void testArrayOfNothing() throws Exception {

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

@@ -35395,6 +35395,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
             KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/testsWithStdLib"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
         }
 
+        @Test
+        @TestMetadata("ambiguityWithUnsignedSpecificity.kt")
+        public void testAmbiguityWithUnsignedSpecificity() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt");
+        }
+
         @Test
         @TestMetadata("ArrayOfNothing.kt")
         public void testArrayOfNothing() throws Exception {

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/AbstractConeCallConflictResolver.kt

@@ -12,6 +12,8 @@ import org.jetbrains.kotlin.fir.resolve.FirSamResolver
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.inference.InferenceComponents
 import org.jetbrains.kotlin.fir.types.*
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.StandardClassIds
 import org.jetbrains.kotlin.name.StandardClassIds.Byte
 import org.jetbrains.kotlin.name.StandardClassIds.Double
 import org.jetbrains.kotlin.name.StandardClassIds.Float
@@ -79,6 +81,12 @@ abstract class AbstractConeCallConflictResolver(
             val specificClassId = specific.lowerBoundIfFlexible().classId ?: return false
             val generalClassId = general.upperBoundIfFlexible().classId ?: return false
 
+            // any signed >= any unsigned
+
+            if (!specificClassId.isUnsigned && generalClassId.isUnsigned) {
+                return true
+            }
+
             // int >= long, int >= short, short >= byte
 
             if (specificClassId == Int) {
@@ -99,6 +107,8 @@ abstract class AbstractConeCallConflictResolver(
 
             return specificClassId == Double && generalClassId == Float
         }
+
+        private val ClassId.isUnsigned get() = this in StandardClassIds.unsignedTypes
     }
 
     protected fun createFlatSignature(call: Candidate): FlatSignature<Candidate> {

compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt

@@ -0,0 +1,12 @@
+// FIR_IDENTICAL
+// ISSUE: KT-57568
+
+fun <T, K> T.convert(): K = null!!
+
+fun of(size: ULong) {
+    of(size.convert())
+}
+
+fun of(size: Int) {}
+
+fun of(size: Long) {}

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

@@ -36143,6 +36143,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
             KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/testsWithStdLib"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
         }
 
+        @Test
+        @TestMetadata("ambiguityWithUnsignedSpecificity.kt")
+        public void testAmbiguityWithUnsignedSpecificity() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/ambiguityWithUnsignedSpecificity.kt");
+        }
+
         @Test
         @TestMetadata("ArrayOfNothing.kt")
         public void testArrayOfNothing() throws Exception {