[FIR] Enable ForbidInferringTypeVariablesIntoEmptyIntersection in 2.0

#KT-56377

compiler/testData/diagnostics/tests/inference/coercionToUnit/afterBareReturn.fir.kt

@@ -29,7 +29,7 @@ fun test3() = run {
 
 fun test4() = run {
     if (p) return@run
-    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>incompatibleC<!>() // ? either uninferred T or error (Unit </: C)
+    <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>incompatibleC<!>() // ? either uninferred T or error (Unit </: C)
 }
 
 fun main() {

compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionToUnitWithNothingType.fir.kt

@@ -47,7 +47,7 @@ fun test(i: Inv<Nothing>, iUnit: Inv<Unit>) {
 
     if (iUnit is String) {
         launch {
-            run(A.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>flexible<!>(iUnit)) { 42 }
+            run(A.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>flexible<!>(iUnit)) { 42 }
         }
     }
 }

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/emptyIntersectionOnIf.fir.kt

@@ -4,5 +4,5 @@ open class A
 abstract class B {
     fun test(current: A): A? =
         // K2 reports empty intersection here due to the smart cast from A to B, where A & B aren't compatible
-        <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING("K; B?, A?; multiple incompatible classes; : B, A")!>if (current === this) current else null<!>
+        <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR("K; B?, A?; multiple incompatible classes; : B, A")!>if (current === this) current else null<!>
 }

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461.diag.txt

@@ -1,6 +1,6 @@
 /kt45461.kt:7:25: warning: parameter 'foo' is never used
     fun <S : T> takeFoo(foo: Foo<in S>) {}
                         ^
-/kt45461.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, Int (multiple incompatible classes). This will become an error in a future release
+/kt45461.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, Int (multiple incompatible classes). This will become an error in Kotlin 2.0
     Bar<String>().takeFoo(foo) // error in 1.3.72, no error in 1.4.31
                   ^

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461.fir.diag.txt

@@ -1 +1 @@
-/kt45461.kt:(245,252): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, kotlin/Int (multiple incompatible classes). This will become an error in a future release
+/kt45461.kt:(245,252): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, kotlin/Int (multiple incompatible classes). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_12.diag.txt

@@ -1,7 +1,7 @@
 /kt45461_12.kt:7:25: warning: parameter 'foo' is never used
     fun <S : T> takeFoo(foo: Foo<in S>) {}
                         ^
-/kt45461_12.kt:14:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Number). This will become an error in a future release
+/kt45461_12.kt:14:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Number). This will become an error in Kotlin 2.0
     Bar<String>().takeFoo(foo) // error in 1.3.72, no error in 1.4.31
                   ^
 

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_12.fir.diag.txt

@@ -1 +1 @@
-/kt45461_12.kt:(296,303): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Number). This will become an error in a future release
+/kt45461_12.kt:(296,303): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Number). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_2.diag.txt

@@ -4,7 +4,7 @@
 /kt45461_2.kt:10:10: warning: 'Int' is a final type, and thus a value of the type parameter is predetermined
 fun <K : Int> main() {
          ^
-/kt45461_2.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Int). This will become an error in a future release
+/kt45461_2.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Int). This will become an error in Kotlin 2.0
     Bar<String>().takeFoo(foo) // error in 1.3.72, no error in 1.4.31
                   ^
 

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_2.fir.diag.txt

@@ -1,3 +1,3 @@
 /kt45461_2.kt:(198,201): warning: 'kotlin/Int' is a final type, and thus a value of the type parameter is predetermined
 
-/kt45461_2.kt:(253,260): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Int). This will become an error in a future release
+/kt45461_2.kt:(253,260): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Int). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_5.diag.txt

@@ -1,6 +1,6 @@
 /kt45461_5.kt:7:25: warning: parameter 'foo' is never used
     fun <S : T> takeFoo(foo: Foo<in S>) {}
                         ^
-/kt45461_5.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Number). This will become an error in a future release
+/kt45461_5.kt:12:19: warning: type argument for a type parameter S can't be inferred because it has incompatible upper bounds: String, K (multiple incompatible classes: String, Number). This will become an error in Kotlin 2.0
     Bar<String>().takeFoo(foo) // error in 1.3.72, no error in 1.4.31
                   ^

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt45461_5.fir.diag.txt

@@ -1 +1 @@
-/kt45461_5.kt:(269,276): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Number). This will become an error in a future release
+/kt45461_5.kt:(269,276): warning: Type argument for a type parameter S can't be inferred because it has incompatible upper bounds: kotlin/String, K (multiple incompatible classes: kotlin/String, kotlin/Number). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt48765.diag.txt

@@ -4,7 +4,7 @@
 /kt48765.kt:6:52: warning: parameter 'x2' is never used
     fun <T1: Number, T2: A<Float, T1>> foo(x1: T2, x2: T1) {}
                                                    ^
-/kt48765.kt:10:13: warning: type argument for a type parameter T can't be inferred because it has incompatible upper bounds: String, Number (multiple incompatible classes). This will become an error in a future release
+/kt48765.kt:10:13: warning: type argument for a type parameter T can't be inferred because it has incompatible upper bounds: String, Number (multiple incompatible classes). This will become an error in Kotlin 2.0
         B().foo(x, foo())
             ^
 /kt48765.kt:14:9: warning: 'String' is a final type, and thus a value of the type parameter is predetermined

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt48765.fir.diag.txt

@@ -1,4 +1,4 @@
-/kt48765.kt:(282,285): warning: Type argument for a type parameter T can't be inferred because it has incompatible upper bounds: kotlin/String, kotlin/Number (multiple incompatible classes). This will become an error in a future release
+/kt48765.kt:(282,285): warning: Type argument for a type parameter T can't be inferred because it has incompatible upper bounds: kotlin/String, kotlin/Number (multiple incompatible classes). This will become an error in Kotlin 2.0
 
 /kt48765.kt:(345,351): warning: 'kotlin/String' is a final type, and thus a value of the type parameter is predetermined
 

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt48987.fir.kt

@@ -5,7 +5,7 @@ fun box(): String {
     return try {
         val range1 = 0..1
         range1 <!CAST_NEVER_SUCCEEDS!>as<!> List<Double>
-        range1.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>joinToString<!> { "" }
+        range1.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>joinToString<!> { "" }
     } catch (e: java.lang.ClassCastException) {
         "OK"
     }

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt49661.diag.txt

@@ -1,4 +1,4 @@
-/kt49661.kt:12:5: warning: type argument for a type parameter T can't be inferred because it has incompatible upper bounds: Foo, Int (multiple incompatible classes). This will become an error in a future release
+/kt49661.kt:11:5: warning: type argument for a type parameter T can't be inferred because it has incompatible upper bounds: Foo, Int (multiple incompatible classes). This will become an error in Kotlin 2.0
     f<Int> { g() }
     ^
 

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/kt49661.fir.diag.txt

@@ -1 +1 @@
-/kt49661.kt:(251,252): warning: Type argument for a type parameter T can't be inferred because it has incompatible upper bounds: Foo, kotlin/Int (multiple incompatible classes). This will become an error in a future release
+/kt49661.fir.kt:(243,244): warning: Type argument for a type parameter T can't be inferred because it has incompatible upper bounds: Foo, kotlin/Int (multiple incompatible classes). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/selectFromCovariantAndContravariantTypes.diag.txt

@@ -7,6 +7,6 @@ fun <V> genericIn(x: In<V>) {}
 /selectFromCovariantAndContravariantTypes.kt:14:20: warning: parameter 'x' is never used
 fun <V> genericOut(x: Out<V>) {}
                    ^
-/selectFromCovariantAndContravariantTypes.kt:17:5: warning: type argument for a type parameter V can't be inferred because it has incompatible upper bounds: A, B (multiple incompatible classes). This will become an error in a future release
+/selectFromCovariantAndContravariantTypes.kt:17:5: warning: type argument for a type parameter V can't be inferred because it has incompatible upper bounds: A, B (multiple incompatible classes). This will become an error in Kotlin 2.0
     genericIn(select(a, b))
     ^

compiler/testData/diagnostics/tests/inference/emptyIntersectionTypes/selectFromCovariantAndContravariantTypes.fir.diag.txt

@@ -1 +1 @@
-/selectFromCovariantAndContravariantTypes.kt:(335,344): warning: Type argument for a type parameter V can't be inferred because it has incompatible upper bounds: A, B (multiple incompatible classes). This will become an error in a future release
+/selectFromCovariantAndContravariantTypes.kt:(335,344): warning: Type argument for a type parameter V can't be inferred because it has incompatible upper bounds: A, B (multiple incompatible classes). This will become an error in Kotlin 2.0

compiler/testData/diagnostics/tests/typeParameters/dontIntersectUpperBoundWithExpectedType.fir.kt

@@ -9,7 +9,7 @@ fun <T : Foo> foo(): T? {
 }
 
 fun main() {
-    val a: Bar? = <!DEBUG_INFO_EXPRESSION_TYPE("Foo? & Bar?")!><!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>foo<!>()<!>
+    val a: Bar? = <!DEBUG_INFO_EXPRESSION_TYPE("Foo? & Bar?")!><!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>foo<!>()<!>
 }
 
 

compiler/testData/diagnostics/tests/typeParameters/kt46186withEmptyIntersections.kt

@@ -1,6 +1,7 @@
 // FIR_IDENTICAL
 // !DIAGNOSTICS: -FINAL_UPPER_BOUND -CAST_NEVER_SUCCEEDS
 // !LANGUAGE: +AllowEmptyIntersectionsInResultTypeResolver
+// !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
 
 interface I
 

compiler/testData/diagnostics/testsWithStdLib/greater.kt

@@ -1,4 +1,5 @@
 // FIR_IDENTICAL
+// !LANGUAGE: -ForbidInferringTypeVariablesIntoEmptyIntersection
 class Expression<T>(val x: T)
 
 class GreaterOp(val expr1: Expression<*>, val expr2: Expression<*>)

compiler/testData/diagnostics/testsWithStdLib/inference/annotationsForResolve/exactAnnotation.fir.kt

@@ -7,5 +7,5 @@ fun test1(l: List<Number>) {
 
     val i: Int = l.firstTyped()
 
-    val s: String = l.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_WARNING!>firstTyped<!>()
+    val s: String = l.<!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION_ERROR!>firstTyped<!>()
 }

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -292,6 +292,7 @@ enum class LanguageFeature(
     ProhibitOpenValDeferredInitialization(KOTLIN_2_0, kind = BUG_FIX), // KT-57553
     ProhibitMissedMustBeInitializedWhenThereIsNoPrimaryConstructor(KOTLIN_2_0, kind = BUG_FIX), // KT-58472
     MangleCallsToJavaMethodsWithValueClasses(KOTLIN_2_0, kind = OTHER), // KT-55945
+    ForbidInferringTypeVariablesIntoEmptyIntersection(KOTLIN_2_0, kind = BUG_FIX), // KT-51221
 
     // 2.1
 
@@ -347,7 +348,6 @@ enum class LanguageFeature(
     EnableDfaWarningsInK2(sinceVersion = null, kind = OTHER), // KT-50965
     ContractSyntaxV2(sinceVersion = null, kind = UNSTABLE_FEATURE), // KT-56127
     ImplicitSignedToUnsignedIntegerConversion(sinceVersion = null), // KT-56583
-    ForbidInferringTypeVariablesIntoEmptyIntersection(sinceVersion = null, kind = BUG_FIX), // KT-51221
     IntrinsicConstEvaluation(sinceVersion = null, kind = UNSTABLE_FEATURE), // KT-49303
     DisableCheckingChangedProgressionsResolve(sinceVersion = null, kind = OTHER), // KT-49276
     ContextSensitiveEnumResolutionInWhen(sinceVersion = null, kind = UNSTABLE_FEATURE), // KT-52774