From b87c2a15b5119a7a80ab869ca6eb5886cace60cc Mon Sep 17 00:00:00 2001
From: Victor Petukhov <victor.petukhov@jetbrains.com>
Date: Wed, 3 Mar 2021 16:34:00 +0300
Subject: [PATCH] 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
---
 ...irOldFrontendDiagnosticsTestGenerated.java |  6 ++++++
 .../components/ConstraintInjector.kt          | 11 -----------
 compiler/testData/diagnostics/tests/Bounds.kt |  4 ++--
 .../tests/generics/innerClasses/innerTP.kt    |  2 +-
 .../manyConstraintsDueToFlexibleRawTypes.kt   |  2 +-
 .../classTypeParameterInferredFromArgument.kt |  2 +-
 .../j+k/genericConstructor/innerClass.kt      |  2 +-
 .../tests/typeParameters/kt42042.fir.kt       | 11 +++++++++++
 .../tests/typeParameters/kt42042.kt           | 11 +++++++++++
 .../tests/typeParameters/kt42042.txt          | 19 +++++++++++++++++++
 ...boundsViolationInDeepTypeAliasExpansion.kt |  2 +-
 .../boundsViolationInTypeAliasExpansion.kt    |  2 +-
 .../test/runners/DiagnosticTestGenerated.java |  6 ++++++
 13 files changed, 61 insertions(+), 19 deletions(-)
 create mode 100644 compiler/testData/diagnostics/tests/typeParameters/kt42042.fir.kt
 create mode 100644 compiler/testData/diagnostics/tests/typeParameters/kt42042.kt
 create mode 100644 compiler/testData/diagnostics/tests/typeParameters/kt42042.txt

diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
index 3b262b3bfb4..e4b96f629b0 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
+++ b/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 {
diff --git a/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt b/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt
index 61eca16a127..fd7d66d76f5 100644
--- a/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/ConstraintInjector.kt
+++ b/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
-            }
         }
     }
 
diff --git a/compiler/testData/diagnostics/tests/Bounds.kt b/compiler/testData/diagnostics/tests/Bounds.kt
index d91a22dc5c3..1f0a3c601b9 100644
--- a/compiler/testData/diagnostics/tests/Bounds.kt
+++ b/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
diff --git a/compiler/testData/diagnostics/tests/generics/innerClasses/innerTP.kt b/compiler/testData/diagnostics/tests/generics/innerClasses/innerTP.kt
index 1e47b515c93..96d0f0e7574 100644
--- a/compiler/testData/diagnostics/tests/generics/innerClasses/innerTP.kt
+++ b/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())
diff --git a/compiler/testData/diagnostics/tests/inference/constraints/manyConstraintsDueToFlexibleRawTypes.kt b/compiler/testData/diagnostics/tests/inference/constraints/manyConstraintsDueToFlexibleRawTypes.kt
index d19f12d2a13..163308f508e 100644
--- a/compiler/testData/diagnostics/tests/inference/constraints/manyConstraintsDueToFlexibleRawTypes.kt
+++ b/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<!>
 }
diff --git a/compiler/testData/diagnostics/tests/j+k/genericConstructor/classTypeParameterInferredFromArgument.kt b/compiler/testData/diagnostics/tests/j+k/genericConstructor/classTypeParameterInferredFromArgument.kt
index 448249692cd..151342d0422 100644
--- a/compiler/testData/diagnostics/tests/j+k/genericConstructor/classTypeParameterInferredFromArgument.kt
+++ b/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)
 }
diff --git a/compiler/testData/diagnostics/tests/j+k/genericConstructor/innerClass.kt b/compiler/testData/diagnostics/tests/j+k/genericConstructor/innerClass.kt
index fd9bb366698..b63c804e0cc 100644
--- a/compiler/testData/diagnostics/tests/j+k/genericConstructor/innerClass.kt
+++ b/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)
 }
diff --git a/compiler/testData/diagnostics/tests/typeParameters/kt42042.fir.kt b/compiler/testData/diagnostics/tests/typeParameters/kt42042.fir.kt
new file mode 100644
index 00000000000..cc6fee6ab05
--- /dev/null
+++ b/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)
+}
diff --git a/compiler/testData/diagnostics/tests/typeParameters/kt42042.kt b/compiler/testData/diagnostics/tests/typeParameters/kt42042.kt
new file mode 100644
index 00000000000..e127db69652
--- /dev/null
+++ b/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)
+}
diff --git a/compiler/testData/diagnostics/tests/typeParameters/kt42042.txt b/compiler/testData/diagnostics/tests/typeParameters/kt42042.txt
new file mode 100644
index 00000000000..1472e3562e1
--- /dev/null
+++ b/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
+    }
+}
diff --git a/compiler/testData/diagnostics/tests/typealias/boundsViolationInDeepTypeAliasExpansion.kt b/compiler/testData/diagnostics/tests/typealias/boundsViolationInDeepTypeAliasExpansion.kt
index fcf532a4be2..55aee58d27e 100644
--- a/compiler/testData/diagnostics/tests/typealias/boundsViolationInDeepTypeAliasExpansion.kt
+++ b/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><!>>()
diff --git a/compiler/testData/diagnostics/tests/typealias/boundsViolationInTypeAliasExpansion.kt b/compiler/testData/diagnostics/tests/typealias/boundsViolationInTypeAliasExpansion.kt
index 66998fd9bfe..98590c1db64 100644
--- a/compiler/testData/diagnostics/tests/typealias/boundsViolationInTypeAliasExpansion.kt
+++ b/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><!>>()
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
index 519a7a1a6cf..5077b3dd679 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
+++ b/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 {