[NI] Decrease priority of Integer Literal Types in type checking

#KT-30446

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/components/ResultTypeResolver.kt

@@ -25,6 +25,9 @@ import org.jetbrains.kotlin.resolve.calls.inference.model.checkConstraint
 import org.jetbrains.kotlin.resolve.constants.IntegerLiteralTypeConstructor
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.intersectTypes
+import org.jetbrains.kotlin.types.checker.isIntegerLiteralType
+import org.jetbrains.kotlin.types.typeUtil.contains
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 class ResultTypeResolver(
     val typeApproximator: TypeApproximator,
@@ -87,7 +90,8 @@ class ResultTypeResolver(
     private fun findSubType(c: Context, variableWithConstraints: VariableWithConstraints): UnwrappedType? {
         val lowerConstraints = variableWithConstraints.constraints.filter { it.kind == ConstraintKind.LOWER && c.isProperType(it.type) }
         if (lowerConstraints.isNotEmpty()) {
-            val commonSuperType = NewCommonSuperTypeCalculator.commonSuperType(lowerConstraints.map { it.type })
+            val types = sinkIntegerLiteralTypes(lowerConstraints.map { it.type })
+            val commonSuperType = NewCommonSuperTypeCalculator.commonSuperType(types)
             /**
              *
              * fun <T> Array<out T>.intersect(other: Iterable<T>) {
@@ -115,6 +119,14 @@ class ResultTypeResolver(
         return null
     }
 
+    private fun sinkIntegerLiteralTypes(types: List<UnwrappedType>): List<UnwrappedType> {
+        return types.sortedBy { type ->
+
+            val containsILT = type.contains { it.unwrap().safeAs<SimpleType>()?.isIntegerLiteralType ?: false }
+            if (containsILT) 1 else 0
+        }
+    }
+
     private fun findSuperType(c: Context, variableWithConstraints: VariableWithConstraints): UnwrappedType? {
         val upperConstraints = variableWithConstraints.constraints.filter { it.kind == ConstraintKind.UPPER && c.isProperType(it.type) }
         if (upperConstraints.isNotEmpty()) {

compiler/testData/diagnostics/testsWithStdLib/inference/integerLiterals.kt

@@ -0,0 +1,24 @@
+// !LANGUAGE: +NewInference
+// !WITH_NEW_INFERENCE
+// !DIAGNOSTICS: -USELESS_ELVIS -UNUSED_EXPRESSION
+
+class X {
+    fun toLong(): Long? = TODO()
+}
+
+fun getLong(): Long = TODO()
+
+fun test_1(list: List<X>) {
+    val props = list.map { <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Long?")!>it.toLong()<!> ?: <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Long")!>0<!> }
+    <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.List<kotlin.Long>")!>props<!>
+}
+
+fun test_2(cond: Boolean) {
+    val props = if (cond) getLong() else 0
+    <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Long")!>props<!>
+}
+
+fun test_3(list: List<X>) {
+    val props = list.map { Pair(it.toLong() ?: 0, it.toLong() ?: 0) }
+    <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.List<kotlin.Pair<kotlin.Long, kotlin.Long>>")!>props<!>
+}

compiler/testData/diagnostics/testsWithStdLib/inference/integerLiterals.txt

@@ -0,0 +1,14 @@
+package
+
+public fun getLong(): kotlin.Long
+public fun test_1(/*0*/ list: kotlin.collections.List<X>): kotlin.Unit
+public fun test_2(/*0*/ cond: kotlin.Boolean): kotlin.Unit
+public fun test_3(/*0*/ list: kotlin.collections.List<X>): kotlin.Unit
+
+public final class X {
+    public constructor X()
+    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 final fun toLong(): kotlin.Long?
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestWithStdLibGenerated.java

@@ -2646,6 +2646,11 @@ public class DiagnosticsTestWithStdLibGenerated extends AbstractDiagnosticsTestW
             runTest("compiler/testData/diagnostics/testsWithStdLib/inference/arrayConstructor.kt");
         }
 
+        @TestMetadata("integerLiterals.kt")
+        public void testIntegerLiterals() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/inference/integerLiterals.kt");
+        }
+
         @TestMetadata("kt11266.kt")
         public void testKt11266() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithStdLib/inference/kt11266.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsTestWithStdLibUsingJavacGenerated.java

@@ -2646,6 +2646,11 @@ public class DiagnosticsTestWithStdLibUsingJavacGenerated extends AbstractDiagno
             runTest("compiler/testData/diagnostics/testsWithStdLib/inference/arrayConstructor.kt");
         }
 
+        @TestMetadata("integerLiterals.kt")
+        public void testIntegerLiterals() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/inference/integerLiterals.kt");
+        }
+
         @TestMetadata("kt11266.kt")
         public void testKt11266() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithStdLib/inference/kt11266.kt");