[NI] Fix coercion to Unit for explicitly specified type argument

#KT-25424 Fixed

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

@@ -25,7 +25,7 @@ class PostponedArgumentsAnalyzer(
         // type can be proper if it not contains not fixed type variables
         fun canBeProper(type: UnwrappedType): Boolean
 
-        fun hasUpperUnitConstraint(type: UnwrappedType): Boolean
+        fun hasUpperOrEqualUnitConstraint(type: UnwrappedType): Boolean
 
         // mutable operations
         fun addOtherSystem(otherSystem: ConstraintStorage)
@@ -76,7 +76,7 @@ class PostponedArgumentsAnalyzer(
             c.canBeProper(rawReturnType) -> substitute(rawReturnType)
 
             // For Unit-coercion
-            c.hasUpperUnitConstraint(rawReturnType) -> lambda.returnType.builtIns.unitType
+            c.hasUpperOrEqualUnitConstraint(rawReturnType) -> lambda.returnType.builtIns.unitType
 
             else -> null
         }

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/model/NewConstraintSystemImpl.kt

@@ -289,11 +289,11 @@ class NewConstraintSystemImpl(
     }
 
     // PostponedArgumentsAnalyzer.Context
-    override fun hasUpperUnitConstraint(type: UnwrappedType): Boolean {
+    override fun hasUpperOrEqualUnitConstraint(type: UnwrappedType): Boolean {
         checkState(State.BUILDING, State.COMPLETION, State.FREEZED)
 
         val constraints = storage.notFixedTypeVariables[type.constructor]?.constraints ?: return false
 
-        return constraints.any { it.kind == ConstraintKind.UPPER && it.type.isUnit() }
+        return constraints.any { (it.kind == ConstraintKind.UPPER || it.kind == ConstraintKind.EQUALITY) && it.type.isUnit() }
     }
 }

compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExplicitTypeArgument.kt

@@ -0,0 +1,10 @@
+// !LANGUAGE: +NewInference
+// !DIAGNOSTICS: -UNUSED_EXPRESSION -UNUSED_VARIABLE
+
+fun foo() {
+    val f = myRun<Unit> {
+        123
+    }
+}
+
+fun <R> myRun(block: () -> R): R = block()

compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExplicitTypeArgument.txt

@@ -0,0 +1,4 @@
+package
+
+public fun foo(): kotlin.Unit
+public fun </*0*/ R> myRun(/*0*/ block: () -> R): R

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

@@ -9685,6 +9685,11 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                     runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExpectedTypeAndBound.kt");
                 }
 
+                @TestMetadata("coercionWithExplicitTypeArgument.kt")
+                public void testCoercionWithExplicitTypeArgument() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExplicitTypeArgument.kt");
+                }
+
                 @TestMetadata("coercionWithoutExpectedType.kt")
                 public void testCoercionWithoutExpectedType() throws Exception {
                     runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithoutExpectedType.kt");

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

@@ -9685,6 +9685,11 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                     runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExpectedTypeAndBound.kt");
                 }
 
+                @TestMetadata("coercionWithExplicitTypeArgument.kt")
+                public void testCoercionWithExplicitTypeArgument() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithExplicitTypeArgument.kt");
+                }
+
                 @TestMetadata("coercionWithoutExpectedType.kt")
                 public void testCoercionWithoutExpectedType() throws Exception {
                     runTest("compiler/testData/diagnostics/tests/inference/coercionToUnit/coercionWithoutExpectedType.kt");