Don't stop constraints processing if all type variables have proper equality constraints

Those type variable may have other constraints after incorporation into which, the constraint error may appear

^KT-42042 Fixed

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

@@ -28773,6 +28773,12 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
                 runTest("compiler/testData/diagnostics/tests/typeParameters/implicitNothingOnDelegates.kt");
             }
 
+            @Test
+            @TestMetadata("kt42042.kt")
+            public void testKt42042() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/typeParameters/kt42042.kt");
+            }
+
             @Test
             @TestMetadata("kt42396.kt")
             public void testKt42396() throws Exception {

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

@@ -122,17 +122,6 @@ class ConstraintInjector(
                     constraintIncorporator.incorporate(typeCheckerContext, typeVariable, constraintToIncorporate)
                 }
             }
-
-            val contextOps = c as? ConstraintSystemOperation
-            if (!typeCheckerContext.hasConstraintsToProcess() ||
-                (contextOps != null && c.notFixedTypeVariables.all { typeVariable ->
-                    typeVariable.value.constraints.any { constraint ->
-                        constraint.kind == EQUALITY && contextOps.isProperType(constraint.type)
-                    }
-                })
-            ) {
-                break
-            }
         }
     }
 

compiler/testData/diagnostics/tests/Bounds.kt

@@ -7,12 +7,12 @@ package boundsWithSubstitutors
     class C : A<C>()
 
     val a = B<C>()
-    val a1 = B<<!UPPER_BOUND_VIOLATED!>Int<!>>()
+    val a1 = B<<!UPPER_BOUND_VIOLATED, UPPER_BOUND_VIOLATED!>Int<!>>()
 
     class X<A, B : A>()
 
     val b = X<Any, X<A<C>, C>>()
-    val b0 = X<Any, <!UPPER_BOUND_VIOLATED!>Any?<!>>()
+    val b0 = X<Any, <!UPPER_BOUND_VIOLATED, UPPER_BOUND_VIOLATED!>Any?<!>>()
     val b1 = X<Any, X<A<C>, <!UPPER_BOUND_VIOLATED!>String<!>>>()
 
 // FILE: b.kt

compiler/testData/diagnostics/tests/generics/innerClasses/innerTP.kt

@@ -32,7 +32,7 @@ fun main() {
     checkSubtype<Outer<*>.Inner<*>>(outer.Inner<Int>())
 
     checkSubtype<Outer<CharSequence>.Inner<CharSequence>>(<!TYPE_MISMATCH!>outer.bar()<!>)
-    checkSubtype<Outer<CharSequence>.Inner<CharSequence>>(<!TYPE_MISMATCH{NI}!>outer.<!TYPE_INFERENCE_EXPECTED_TYPE_MISMATCH{OI}!>Inner()<!><!>)
+    checkSubtype<Outer<CharSequence>.Inner<CharSequence>>(<!TYPE_MISMATCH{NI}, TYPE_MISMATCH!>outer.<!TYPE_INFERENCE_EXPECTED_TYPE_MISMATCH{OI}!>Inner()<!><!>)
 
     outer.set(outer.bar())
     outer.set(outer.Inner())

compiler/testData/diagnostics/tests/inference/constraints/manyConstraintsDueToFlexibleRawTypes.kt

@@ -28,5 +28,5 @@ abstract class MySettingsListener<S extends MyComparableSettings> {}
 fun test() {
     val a = MySettings.getSettings()
     a.getLinkedProjectsSettings()
-    a.<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE{OI}, TYPE_INFERENCE_UPPER_BOUND_VIOLATED{OI}!>linkedProjectsSettings<!>
+    a.<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE{OI}, TYPE_INFERENCE_UPPER_BOUND_VIOLATED{OI}, UNRESOLVED_REFERENCE_WRONG_RECEIVER!>linkedProjectsSettings<!>
 }

compiler/testData/diagnostics/tests/j+k/genericConstructor/classTypeParameterInferredFromArgument.kt

@@ -12,6 +12,6 @@ fun test(x: List<Int>, y: List<String>) {
     A("", x) checkType { <!UNRESOLVED_REFERENCE_WRONG_RECEIVER{NI}!>_<!><A<Any?>>() }
     A("", y) checkType { _<A<String?>>() }
 
-    A<CharSequence, String>("", <!TYPE_MISMATCH{NI}, TYPE_MISMATCH!>x<!>)
+    A<CharSequence, String>("", <!TYPE_MISMATCH{NI}, TYPE_MISMATCH, TYPE_MISMATCH!>x<!>)
     A<CharSequence, String>("", y)
 }

compiler/testData/diagnostics/tests/j+k/genericConstructor/innerClass.kt

@@ -14,5 +14,5 @@ fun test(x: List<Int>, y: List<String>) {
     Outer<Int>().Inner<CharSequence, String, Int>("", y, 1) checkType { _<Outer<Int>.Inner<CharSequence>>() }
 
     Outer<Int>().Inner("", x, 1) checkType { <!UNRESOLVED_REFERENCE_WRONG_RECEIVER{NI}!>_<!><Outer<Int>.Inner<Any>>() }
-    Outer<Int>().Inner<CharSequence, String, Int>("", <!TYPE_MISMATCH{NI}, TYPE_MISMATCH!>x<!>, 1)
+    Outer<Int>().Inner<CharSequence, String, Int>("", <!TYPE_MISMATCH{NI}, TYPE_MISMATCH, TYPE_MISMATCH!>x<!>, 1)
 }

compiler/testData/diagnostics/tests/typeParameters/kt42042.fir.kt

@@ -0,0 +1,11 @@
+sealed class Subtype<A1, B1> {
+    abstract fun cast(value: A1): B1
+    class Trivial<A2 : B2, B2> : Subtype<A2, B2>() {
+        override fun cast(value: A2): B2 = value
+    }
+}
+
+fun <A, B> unsafeCast(value: A): B {
+    val proof: Subtype<A, B> = Subtype.Trivial()
+    return proof.cast(value)
+}

compiler/testData/diagnostics/tests/typeParameters/kt42042.kt

@@ -0,0 +1,11 @@
+sealed class Subtype<A1, B1> {
+    abstract fun cast(value: A1): B1
+    class Trivial<A2 : B2, B2> : Subtype<A2, B2>() {
+        override fun cast(value: A2): B2 = value
+    }
+}
+
+fun <A, B> unsafeCast(value: A): B {
+    val proof: Subtype<A, B> = Subtype.<!TYPE_MISMATCH, TYPE_MISMATCH!>Trivial()<!>
+    return proof.cast(value)
+}

compiler/testData/diagnostics/tests/typeParameters/kt42042.txt

@@ -0,0 +1,19 @@
+package
+
+public fun </*0*/ A, /*1*/ B> unsafeCast(/*0*/ value: A): B
+
+public sealed class Subtype</*0*/ A1, /*1*/ B1> {
+    protected constructor Subtype</*0*/ A1, /*1*/ B1>()
+    public abstract fun cast(/*0*/ value: A1): B1
+    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 open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    public final class Trivial</*0*/ A2 : B2, /*1*/ B2> : Subtype<A2, B2> {
+        public constructor Trivial</*0*/ A2 : B2, /*1*/ B2>()
+        public open override /*1*/ fun cast(/*0*/ value: A2): B2
+        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 open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}

compiler/testData/diagnostics/tests/typealias/boundsViolationInDeepTypeAliasExpansion.kt

@@ -14,4 +14,4 @@ fun test4(x: <!UPPER_BOUND_VIOLATED_IN_TYPEALIAS_EXPANSION!>TC2<Number, List<Any
 val test5 = TC2<Number, Collection<Number>>()
 val test6 = TC2<Number, Collection<Int>>()
 val test7 = TC2<Number, List<Int>>()
-val test8 = TC2<Number, <!UPPER_BOUND_VIOLATED!>List<Any><!>>()
+val test8 = TC2<Number, <!UPPER_BOUND_VIOLATED, UPPER_BOUND_VIOLATED!>List<Any><!>>()

compiler/testData/diagnostics/tests/typealias/boundsViolationInTypeAliasExpansion.kt

@@ -29,4 +29,4 @@ fun test12(x: TC<Number, <!UPPER_BOUND_VIOLATED!>List<Any><!>>) {}
 val test13 = TC<Number, Collection<Number>>()
 val test14 = TC<Number, Collection<Int>>()
 val test15 = TC<Number, List<Int>>()
-val test16 = TC<Number, <!UPPER_BOUND_VIOLATED!>List<Any><!>>()
+val test16 = TC<Number, <!UPPER_BOUND_VIOLATED, UPPER_BOUND_VIOLATED!>List<Any><!>>()

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

@@ -28869,6 +28869,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/typeParameters/implicitNothingOnDelegates.kt");
             }
 
+            @Test
+            @TestMetadata("kt42042.kt")
+            public void testKt42042() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/typeParameters/kt42042.kt");
+            }
+
             @Test
             @TestMetadata("kt42396.kt")
             public void testKt42396() throws Exception {