NI: Fix type mismatch caused by smartcast

^KT-25434 Fixed

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirOldFrontendDiagnosticsTestGenerated.java

@@ -10023,6 +10023,11 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirOldFronte
             runTest("compiler/testData/diagnostics/tests/inference/starApproximationFlexible.kt");
         }
 
+        @TestMetadata("tooEagerSmartcast.kt")
+        public void testTooEagerSmartcast() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/inference/tooEagerSmartcast.kt");
+        }
+
         @TestMetadata("tryNumberLowerBoundsBeforeUpperBounds.kt")
         public void testTryNumberLowerBoundsBeforeUpperBounds() throws Exception {
             runTest("compiler/testData/diagnostics/tests/inference/tryNumberLowerBoundsBeforeUpperBounds.kt");

compiler/testData/diagnostics/tests/inference/tooEagerSmartcast.fir.kt

@@ -0,0 +1,42 @@
+// SKIP_TXT
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+// !LANGUAGE: +NewInference
+
+interface OutBase<out E>
+interface OutDerived<out F> : OutBase<F>
+
+fun <X> OutBase<X>.myLast(): X = TODO()
+
+fun <T> foo(x: OutBase<T>) {
+    if (x is OutDerived<*>) {
+        val l: T = x.myLast() // required T, found Cap(*). Only in NI
+    }
+}
+
+interface InvBase<E>
+interface InvDerived<F> : InvBase<F>
+
+fun <X> InvBase<X>.myLastInv(): X = TODO()
+
+fun <T> fooInv(x: InvBase<T>) {
+    if (x is InvDerived<*>) {
+        val l: T = x.<!INAPPLICABLE_CANDIDATE!>myLastInv<!>() // required T, found Cap(*). Only in NI
+    }
+}
+
+interface Base<E>
+
+fun <Q> Base<Q>.foo(): Q = TODO()
+fun <Q : CharSequence> Base<Q>.baz(): Q = TODO()
+
+interface Derived<F : CharSequence> : Base<F>
+
+fun Number.num() {}
+
+fun main(b: Base<out Number>) {
+    b.foo().num()
+    if (b is Derived<*>) {
+        b.<!INAPPLICABLE_CANDIDATE!>foo<!>().num()
+        b.<!INAPPLICABLE_CANDIDATE!>baz<!>().<!UNRESOLVED_REFERENCE!>length<!>
+    }
+}

compiler/testData/diagnostics/tests/inference/tooEagerSmartcast.kt

@@ -0,0 +1,42 @@
+// SKIP_TXT
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+// !LANGUAGE: +NewInference
+
+interface OutBase<out E>
+interface OutDerived<out F> : OutBase<F>
+
+fun <X> OutBase<X>.myLast(): X = TODO()
+
+fun <T> foo(x: OutBase<T>) {
+    if (x is OutDerived<*>) {
+        val l: T = x.myLast() // required T, found Cap(*). Only in NI
+    }
+}
+
+interface InvBase<E>
+interface InvDerived<F> : InvBase<F>
+
+fun <X> InvBase<X>.myLastInv(): X = TODO()
+
+fun <T> fooInv(x: InvBase<T>) {
+    if (x is InvDerived<*>) {
+        val l: T = x.myLastInv() // required T, found Cap(*). Only in NI
+    }
+}
+
+interface Base<E>
+
+fun <Q> Base<Q>.foo(): Q = TODO()
+fun <Q : CharSequence> Base<Q>.baz(): Q = TODO()
+
+interface Derived<F : CharSequence> : Base<F>
+
+fun Number.num() {}
+
+fun main(b: Base<out Number>) {
+    b.foo().num()
+    if (b is Derived<*>) {
+        b.foo().num()
+        b.baz().length
+    }
+}

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

@@ -10030,6 +10030,11 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 runTest("compiler/testData/diagnostics/tests/inference/starApproximationFlexible.kt");
             }
 
+            @TestMetadata("tooEagerSmartcast.kt")
+            public void testTooEagerSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/tooEagerSmartcast.kt");
+            }
+
             @TestMetadata("tryNumberLowerBoundsBeforeUpperBounds.kt")
             public void testTryNumberLowerBoundsBeforeUpperBounds() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inference/tryNumberLowerBoundsBeforeUpperBounds.kt");

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

@@ -10025,6 +10025,11 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 runTest("compiler/testData/diagnostics/tests/inference/starApproximationFlexible.kt");
             }
 
+            @TestMetadata("tooEagerSmartcast.kt")
+            public void testTooEagerSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/tooEagerSmartcast.kt");
+            }
+
             @TestMetadata("tryNumberLowerBoundsBeforeUpperBounds.kt")
             public void testTryNumberLowerBoundsBeforeUpperBounds() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inference/tryNumberLowerBoundsBeforeUpperBounds.kt");

core/type-system/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt

@@ -269,8 +269,6 @@ object AbstractTypeChecker {
             1 -> return isSubtypeForSameConstructor(supertypesWithSameConstructor.first().asArgumentList(), superType)
 
             else -> { // at least 2 supertypes with same constructors. Such case is rare
-                if (supertypesWithSameConstructor.any { isSubtypeForSameConstructor(it.asArgumentList(), superType) }) return true
-
                 val newArguments = ArgumentList(superConstructor.parametersCount())
                 for (index in 0 until superConstructor.parametersCount()) {
                     val allProjections = supertypesWithSameConstructor.map {
@@ -283,7 +281,9 @@ object AbstractTypeChecker {
                     newArguments.add(intersection)
                 }
 
-                return isSubtypeForSameConstructor(newArguments, superType)
+                if (isSubtypeForSameConstructor(newArguments, superType)) return true
+
+                return supertypesWithSameConstructor.any { isSubtypeForSameConstructor(it.asArgumentList(), superType) }
             }
         }
     }