[NI] Don't fail on captured type that contains type variable

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

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
+ * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- *
+ * that can be found in the license/LICENSE.txt file.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
  */
 
 package org.jetbrains.kotlin.resolve.calls.inference.components
@@ -83,10 +72,25 @@ abstract class TypeCheckerContextForConstraintSystem : TypeCheckerContext(errorT
         if (subType.anyBound(this::isMyTypeVariable)) {
             return simplifyUpperConstraint(subType, superType) && (answer ?: true)
         } else {
+            extractTypeVariableForSubtype(subType)?.let {
+                return simplifyUpperConstraint(it, superType) && (answer ?: true)
+            }
+
             return simplifyConstraintForPossibleIntersectionSubType(subType, superType) ?: answer
         }
     }
 
+    // extract type variable only from type like Captured(out T)
+    private fun extractTypeVariableForSubtype(type: UnwrappedType): UnwrappedType? {
+        if (type !is NewCapturedType) return null
+
+        val projection = type.constructor.projection
+        return if (projection.projectionKind == Variance.OUT_VARIANCE)
+            projection.type.takeIf { it is SimpleType && isMyTypeVariable(it) }?.unwrap()
+        else
+            null
+    }
+
     /**
      * Foo <: T -- leave as is
      *

compiler/testData/diagnostics/tests/inference/capturedTypes/capturedTypeWithTypeVariableSubtyping.kt

@@ -0,0 +1,22 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+fun takeCovArray(a: Array<out Number>) {}
+fun takeInArray(a: Array<in Number>) {}
+
+fun <T> foo(): Array<out T> = TODO()
+fun <T> bar(): Array<in T> = TODO()
+
+fun <X> id(x: X): X = x
+fun <Z> arrayInId(z: Array<in Z>): Array<in Z> = z
+fun <Z> arrayOutId(z: Array<out Z>): Array<out Z> = z
+
+fun test() {
+    takeCovArray(foo())
+    takeInArray(bar())
+
+    takeCovArray(id(foo()))
+    takeInArray(id(bar()))
+
+    takeCovArray(arrayOutId(foo()))
+    takeInArray(arrayInId(bar()))
+}

compiler/testData/diagnostics/tests/inference/capturedTypes/capturedTypeWithTypeVariableSubtyping.txt

@@ -0,0 +1,10 @@
+package
+
+public fun </*0*/ Z> arrayInId(/*0*/ z: kotlin.Array<in Z>): kotlin.Array<in Z>
+public fun </*0*/ Z> arrayOutId(/*0*/ z: kotlin.Array<out Z>): kotlin.Array<out Z>
+public fun </*0*/ T> bar(): kotlin.Array<in T>
+public fun </*0*/ T> foo(): kotlin.Array<out T>
+public fun </*0*/ X> id(/*0*/ x: X): X
+public fun takeCovArray(/*0*/ a: kotlin.Array<out kotlin.Number>): kotlin.Unit
+public fun takeInArray(/*0*/ a: kotlin.Array<in kotlin.Number>): kotlin.Unit
+public fun test(): kotlin.Unit

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

@@ -18,7 +18,7 @@ fun test1(int: Int, any: Any) {
 
     val a2 : MyList<out Any> = getMyList(int)
 
-    val a3 : MyList<out Any> = <!NI;TYPE_MISMATCH!>getMyListToReadFrom(int)<!>
+    val a3 : MyList<out Any> = getMyListToReadFrom(int)
 
     val a4 : MyList<in Int> = getMyList(any)
 

compiler/testData/diagnostics/tests/regressions/OutProjections.kt

@@ -18,5 +18,5 @@ fun <T> fout(<!UNUSED_PARAMETER!>expression<!> : T) : Out<<!REDUNDANT_PROJECTION
 
 fun fooout() : Out<Point> {
   val p = Point();
-  return <!NI;TYPE_MISMATCH!>fout<Point>(p)<!>;
+  return fout<Point>(p);
 }

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

@@ -10660,6 +10660,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                     doTest(fileName);
                 }
 
+                @TestMetadata("capturedTypeWithTypeVariableSubtyping.kt")
+                public void testCapturedTypeWithTypeVariableSubtyping() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/inference/capturedTypes/capturedTypeWithTypeVariableSubtyping.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("expectedTypeMismatchWithInVariance.kt")
                 public void testExpectedTypeMismatchWithInVariance() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/inference/capturedTypes/expectedTypeMismatchWithInVariance.kt");

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

@@ -10660,6 +10660,12 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                     doTest(fileName);
                 }
 
+                @TestMetadata("capturedTypeWithTypeVariableSubtyping.kt")
+                public void testCapturedTypeWithTypeVariableSubtyping() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/inference/capturedTypes/capturedTypeWithTypeVariableSubtyping.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("expectedTypeMismatchWithInVariance.kt")
                 public void testExpectedTypeMismatchWithInVariance() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/inference/capturedTypes/expectedTypeMismatchWithInVariance.kt");