[NI] Properly detecting suitability of candidate for builder inference

#KT-41430 Fixed

compiler/fir/analysis-tests/tests/org/jetbrains/kotlin/fir/FirOldFrontendDiagnosticsTestWithStdlibGenerated.java

@@ -1737,6 +1737,11 @@ public class FirOldFrontendDiagnosticsTestWithStdlibGenerated extends AbstractFi
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt38179.kt");
         }
 
+        @TestMetadata("kt41430.kt")
+        public void testKt41430() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.kt");
+        }
+
         @TestMetadata("lambdaExpectedType.kt")
         public void testLambdaExpectedType() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/lambdaExpectedType.kt");

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/inference/CoroutineInferenceSession.kt

@@ -90,15 +90,9 @@ class CoroutineInferenceSession(
         val dispatchReceiver = resolvedCall.dispatchReceiverArgument
         return when {
             extensionReceiver == null && dispatchReceiver == null -> false
-            extensionReceiver == null -> true
+            dispatchReceiver?.receiver?.stableType?.containsStubType() == true -> true
-            extensionReceiver.receiver.stableType.containsStubType() -> resolvedCall.candidateDescriptor.hasBuilderInferenceAnnotation()
+            extensionReceiver?.receiver?.stableType?.containsStubType() == true -> resolvedCall.candidateDescriptor.hasBuilderInferenceAnnotation()
-            else -> true
+            else -> false
-        }
-    }
-
-    private fun KotlinType.containsNotFixedTypeVariable(storage: ConstraintStorage): Boolean {
-        return this.contains {
-            it.constructor in storage.notFixedTypeVariables
         }
     }
 

compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.fir.kt

@@ -0,0 +1,27 @@
+// ISSUE: KT-41430
+
+class A
+
+fun test_1(list: List<Set<A>>) {
+    list.<!AMBIGUITY!>flatMapTo<!>(mutableSetOf()) { <!UNRESOLVED_REFERENCE!>it<!> }
+}
+
+fun test_2(list: List<Set<A>>) {
+    sequence<A> {
+        <!DEBUG_INFO_EXPRESSION_TYPE("ERROR CLASS: Ambiguity: flatMapTo, [kotlin/collections/flatMapTo, kotlin/collections/flatMapTo]")!>list.<!AMBIGUITY!>flatMapTo<!>(mutableSetOf()) { <!UNRESOLVED_REFERENCE!>it<!> }<!>
+    }
+}
+
+fun test_3(list: List<Set<A>>) {
+    sequence {
+        list.<!AMBIGUITY!>flatMapTo<!>(mutableSetOf()) { <!UNRESOLVED_REFERENCE!>it<!> }
+        yield(A())
+    }
+}
+
+fun test_4(list: List<Set<A>>) {
+    sequence {
+        yield(A())
+        list.<!AMBIGUITY!>flatMapTo<!>(mutableSetOf()) { <!UNRESOLVED_REFERENCE!>it<!> }
+    }
+}

compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.kt

@@ -0,0 +1,27 @@
+// ISSUE: KT-41430
+
+class A
+
+fun test_1(list: List<Set<A>>) {
+    <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.MutableSet<A>")!>list.flatMapTo(mutableSetOf()) { it }<!>
+}
+
+fun test_2(list: List<Set<A>>) {
+    sequence<A> {
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.MutableSet<A>")!>list.flatMapTo(mutableSetOf()) { it }<!>
+    }
+}
+
+fun test_3(list: List<Set<A>>) {
+    sequence {
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.MutableSet<A>")!>list.flatMapTo(mutableSetOf()) { it }<!>
+        yield(A())
+    }
+}
+
+fun test_4(list: List<Set<A>>) {
+    sequence {
+        yield(A())
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.collections.MutableSet<A>")!>list.flatMapTo(mutableSetOf()) { it }<!>
+    }
+}

compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.txt

@@ -0,0 +1,13 @@
+package
+
+public fun test_1(/*0*/ list: kotlin.collections.List<kotlin.collections.Set<A>>): kotlin.Unit
+public fun test_2(/*0*/ list: kotlin.collections.List<kotlin.collections.Set<A>>): kotlin.Unit
+public fun test_3(/*0*/ list: kotlin.collections.List<kotlin.collections.Set<A>>): kotlin.Unit
+public fun test_4(/*0*/ list: kotlin.collections.List<kotlin.collections.Set<A>>): kotlin.Unit
+
+public final class A {
+    public constructor A()
+    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/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestWithStdLibGenerated.java

@@ -1737,6 +1737,11 @@ public class DiagnosticsTestWithStdLibGenerated extends AbstractDiagnosticsTestW
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt38179.kt");
         }
 
+        @TestMetadata("kt41430.kt")
+        public void testKt41430() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.kt");
+        }
+
         @TestMetadata("lambdaExpectedType.kt")
         public void testLambdaExpectedType() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/lambdaExpectedType.kt");

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

@@ -1737,6 +1737,11 @@ public class DiagnosticsTestWithStdLibUsingJavacGenerated extends AbstractDiagno
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt38179.kt");
         }
 
+        @TestMetadata("kt41430.kt")
+        public void testKt41430() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/kt41430.kt");
+        }
+
         @TestMetadata("lambdaExpectedType.kt")
         public void testLambdaExpectedType() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithStdLib/coroutines/lambdaExpectedType.kt");