FIR: Fix resolution for lambda returning resolved qualifier

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/FirDataFlowAnalyzer.kt

@@ -586,6 +586,10 @@ abstract class FirDataFlowAnalyzer<FLOW : Flow>(
         exitSafeCall(qualifiedAccessExpression)
     }
 
+    fun exitResolvedQualifierNode(resolvedQualifier: FirResolvedQualifier) {
+        graphBuilder.exitResolvedQualifierNode(resolvedQualifier).mergeIncomingFlow()
+    }
+
     fun enterCall(functionCall: FirCall) {
         graphBuilder.enterCall(functionCall)
     }

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/cfg/ControlFlowGraph.kt

@@ -202,6 +202,12 @@ class QualifiedAccessNode(
     level: Int, id: Int
 ) : CFGNode<FirQualifiedAccessExpression>(owner, level, id)
 
+class ResolvedQualifierNode(
+    owner: ControlFlowGraph,
+    override val fir: FirResolvedQualifier,
+    level: Int, id: Int
+) : CFGNode<FirResolvedQualifier>(owner, level, id)
+
 class FunctionCallNode(
     owner: ControlFlowGraph,
     override val fir: FirFunctionCall,

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/cfg/ControlFlowGraphBuilder.kt

@@ -621,6 +621,10 @@ class ControlFlowGraphBuilder {
         return node
     }
 
+    fun exitResolvedQualifierNode(resolvedQualifier: FirResolvedQualifier): ResolvedQualifierNode {
+        return createResolvedQualifierNode(resolvedQualifier).also(this::addNewSimpleNode)
+    }
+
     fun enterCall(call: FirCall) {
         levelCounter++
     }

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/cfg/ControlFlowGraphNodeBuilder.kt

@@ -39,6 +39,9 @@ fun ControlFlowGraphBuilder.createCheckNotNullCallNode(fir: FirCheckNotNullCall)
 fun ControlFlowGraphBuilder.createQualifiedAccessNode(fir: FirQualifiedAccessExpression): QualifiedAccessNode =
     QualifiedAccessNode(graph, fir, levelCounter, createId())
 
+fun ControlFlowGraphBuilder.createResolvedQualifierNode(fir: FirResolvedQualifier): ResolvedQualifierNode =
+    ResolvedQualifierNode(graph, fir, levelCounter, createId())
+
 fun ControlFlowGraphBuilder.createBlockEnterNode(fir: FirBlock): BlockEnterNode = BlockEnterNode(graph, fir, levelCounter, createId())
 
 fun ControlFlowGraphBuilder.createBlockExitNode(fir: FirBlock): BlockExitNode = BlockExitNode(graph, fir, levelCounter, createId())

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/cfg/ControlFlowGraphRenderer.kt

@@ -166,6 +166,7 @@ private fun CFGNode<*>.render(): String =
                 is LoopExitNode -> "Exit ${fir.type()}loop"
 
                 is QualifiedAccessNode -> "Access variable ${fir.calleeReference.render(CfgRenderMode)}"
+                is ResolvedQualifierNode -> "Access qualifier ${fir.classId}"
                 is OperatorCallNode -> "Operator ${fir.operation.operator}"
                 is ComparisonExpressionNode -> "Comparison ${fir.operation.operator}"
                 is TypeOperatorCallNode -> "Type operator: \"${fir.render(CfgRenderMode)}\""

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirExpressionsResolveTransformer.kt

@@ -137,10 +137,15 @@ class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) :
                 }
             }
         }
-        if (result is FirQualifiedAccessExpression) {
-            dataFlowAnalyzer.enterQualifiedAccessExpression(result)
-            result = components.transformQualifiedAccessUsingSmartcastInfo(result)
-            dataFlowAnalyzer.exitQualifiedAccessExpression(result)
+        when (result) {
+            is FirQualifiedAccessExpression -> {
+                dataFlowAnalyzer.enterQualifiedAccessExpression(result)
+                result = components.transformQualifiedAccessUsingSmartcastInfo(result)
+                dataFlowAnalyzer.exitQualifiedAccessExpression(result)
+            }
+            is FirResolvedQualifier -> {
+                dataFlowAnalyzer.exitResolvedQualifierNode(result)
+            }
         }
         return result.compose()
     }

compiler/fir/resolve/testData/resolve/cfg/lambdaReturningObject.dot

+digraph lambdaReturningObject_kt {
+    graph [nodesep=3]
+    node [shape=box penwidth=2]
+    edge [penwidth=2]
+
+    subgraph cluster_0 {
+        color=red
+        0 [label="Enter function bar" style="filled" fillcolor=red];
+        1 [label="Exit function bar" style="filled" fillcolor=red];
+    }
+
+    0 -> {1};
+
+    subgraph cluster_1 {
+        color=red
+        2 [label="Enter function <init>" style="filled" fillcolor=red];
+        3 [label="Delegated constructor call: super<R|kotlin/Any|>()"];
+        4 [label="Exit function <init>" style="filled" fillcolor=red];
+    }
+
+    2 -> {3};
+    3 -> {4};
+
+    subgraph cluster_2 {
+        color=red
+        5 [label="Enter function MyOut" style="filled" fillcolor=red];
+        6 [label="Function call: R|kotlin/TODO|()"];
+        7 [label="Stub" style="filled" fillcolor=gray];
+        8 [label="Jump: ^MyOut R|kotlin/TODO|()" style="filled" fillcolor=gray];
+        9 [label="Stub" style="filled" fillcolor=gray];
+        10 [label="Exit function MyOut" style="filled" fillcolor=red];
+    }
+
+    5 -> {6};
+    6 -> {10};
+    6 -> {7} [style=dotted];
+    7 -> {8} [style=dotted];
+    8 -> {10 9} [style=dotted];
+    9 -> {10} [style=dotted];
+
+    subgraph cluster_3 {
+        color=red
+        11 [label="Enter function foo" style="filled" fillcolor=red];
+        12 [label="Postponed enter to lambda"];
+        13 [label="Postponed exit from lambda"];
+        14 [label="Function call: R|/MyOut|<R|IrStarProjectionImpl|>(...)"];
+        15 [label="Function call: R|/bar|(...)"];
+        16 [label="Exit function foo" style="filled" fillcolor=red];
+    }
+
+    11 -> {12};
+    12 -> {13 13} [color=green];
+    13 -> {14};
+    14 -> {15};
+    15 -> {16};
+
+    subgraph cluster_4 {
+        color=red
+        17 [label="Enter function anonymousFunction" style="filled" fillcolor=red];
+        18 [label="Access qualifier /IrStarProjectionImpl"];
+        19 [label="Exit function anonymousFunction" style="filled" fillcolor=red];
+    }
+
+    17 -> {18};
+    18 -> {19};
+
+}

compiler/fir/resolve/testData/resolve/cfg/lambdaReturningObject.kt

+// !DUMP_CFG
+
+interface Out<out E>
+fun bar(arguments: Out<IrTypeArgument>) {}
+
+interface IrTypeArgument
+
+object IrStarProjectionImpl : IrTypeArgument
+
+fun <T> MyOut(init: () -> T): Out<T> = TODO()
+
+fun foo() {
+    bar(MyOut { IrStarProjectionImpl })
+}

compiler/fir/resolve/testData/resolve/cfg/lambdaReturningObject.txt

+FILE: lambdaReturningObject.kt
+    public abstract interface Out<out E> : R|kotlin/Any| {
+    }
+    public final fun bar(arguments: R|Out<IrTypeArgument>|): R|kotlin/Unit| {
+    }
+    public abstract interface IrTypeArgument : R|kotlin/Any| {
+    }
+    public final object IrStarProjectionImpl : R|IrTypeArgument| {
+        private constructor(): R|IrStarProjectionImpl| {
+            super<R|kotlin/Any|>()
+        }
+
+    }
+    public final fun <T> MyOut(init: R|() -> T|): R|Out<T>| {
+        ^MyOut R|kotlin/TODO|()
+    }
+    public final fun foo(): R|kotlin/Unit| {
+        R|/bar|(R|/MyOut|<R|IrStarProjectionImpl|>(<L> = MyOut@fun <anonymous>(): R|IrStarProjectionImpl| {
+            ^ Q|IrStarProjectionImpl|
+        }
+        ))
+    }

compiler/fir/resolve/testData/resolve/exhaustiveWhenAndDNNType.dot

@@ -50,49 +50,52 @@ digraph exhaustiveWhenAndDNNType_kt {
     subgraph cluster_5 {
         color=red
         12 [label="Enter function test_1" style="filled" fillcolor=red];
-        13 [label="Access variable R|/SomeEnum.A1|"];
-        14 [label="Variable declaration: lval flag: R|SomeEnum|"];
+        13 [label="Access qualifier /SomeEnum"];
+        14 [label="Access variable R|/SomeEnum.A1|"];
+        15 [label="Variable declaration: lval flag: R|SomeEnum|"];
         subgraph cluster_6 {
             color=blue
-            15 [label="Enter when"];
-            16 [label="Access variable R|<local>/flag|"];
-            17 [label="Check not null: R|<local>/flag|!!"];
+            16 [label="Enter when"];
+            17 [label="Access variable R|<local>/flag|"];
+            18 [label="Check not null: R|<local>/flag|!!"];
             subgraph cluster_7 {
                 color=blue
-                18 [label="Enter when branch condition "];
-                19 [label="Access variable R|/SomeEnum.A1|"];
-                20 [label="Operator =="];
-                21 [label="Exit when branch condition"];
+                19 [label="Enter when branch condition "];
+                20 [label="Access qualifier /SomeEnum"];
+                21 [label="Access variable R|/SomeEnum.A1|"];
+                22 [label="Operator =="];
+                23 [label="Exit when branch condition"];
             }
             subgraph cluster_8 {
                 color=blue
-                22 [label="Enter when branch condition "];
-                23 [label="Access variable R|/SomeEnum.A2|"];
-                24 [label="Operator =="];
-                25 [label="Exit when branch condition"];
+                24 [label="Enter when branch condition "];
+                25 [label="Access qualifier /SomeEnum"];
+                26 [label="Access variable R|/SomeEnum.A2|"];
+                27 [label="Operator =="];
+                28 [label="Exit when branch condition"];
             }
-            26 [label="Enter when branch result"];
+            29 [label="Enter when branch result"];
             subgraph cluster_9 {
                 color=blue
-                27 [label="Enter block"];
-                28 [label="Function call: R|/B.B|()"];
-                29 [label="Exit block"];
+                30 [label="Enter block"];
+                31 [label="Function call: R|/B.B|()"];
+                32 [label="Exit block"];
             }
-            30 [label="Exit when branch result"];
-            31 [label="Enter when branch result"];
+            33 [label="Exit when branch result"];
+            34 [label="Enter when branch result"];
             subgraph cluster_10 {
                 color=blue
-                32 [label="Enter block"];
-                33 [label="Function call: R|/B.B|()"];
-                34 [label="Exit block"];
+                35 [label="Enter block"];
+                36 [label="Function call: R|/B.B|()"];
+                37 [label="Exit block"];
             }
-            35 [label="Exit when branch result"];
-            36 [label="Exit when"];
+            38 [label="Exit when branch result"];
+            39 [label="Exit when"];
         }
-        37 [label="Variable declaration: lval b: R|B|"];
-        38 [label="Access variable R|<local>/b|"];
-        39 [label="Function call: R|/takeB|(...)"];
-        40 [label="Exit function test_1" style="filled" fillcolor=red];
+        40 [label="Variable declaration: lval b: R|B|"];
+        41 [label="Access variable R|<local>/b|"];
+        42 [label="Function call: R|/takeB|(...)"];
+        43 [label="Exit function test_1" style="filled" fillcolor=red];
     }
 
     12 -> {13};
@@ -104,159 +107,165 @@ digraph exhaustiveWhenAndDNNType_kt {
     18 -> {19};
     19 -> {20};
     20 -> {21};
-    21 -> {31 22};
+    21 -> {22};
     22 -> {23};
-    23 -> {24};
+    23 -> {34 24};
     24 -> {25};
     25 -> {26};
     26 -> {27};
     27 -> {28};
     28 -> {29};
     29 -> {30};
-    30 -> {36};
+    30 -> {31};
     31 -> {32};
     32 -> {33};
-    33 -> {34};
+    33 -> {39};
     34 -> {35};
     35 -> {36};
     36 -> {37};
     37 -> {38};
     38 -> {39};
     39 -> {40};
+    40 -> {41};
+    41 -> {42};
+    42 -> {43};
 
     subgraph cluster_11 {
         color=red
-        41 [label="Enter function test_2" style="filled" fillcolor=red];
-        42 [label="Access variable R|/SomeEnum.A1|"];
-        43 [label="Variable declaration: lval flag: R|SomeEnum|"];
+        44 [label="Enter function test_2" style="filled" fillcolor=red];
+        45 [label="Access qualifier /SomeEnum"];
+        46 [label="Access variable R|/SomeEnum.A1|"];
+        47 [label="Variable declaration: lval flag: R|SomeEnum|"];
         subgraph cluster_12 {
             color=blue
-            44 [label="Enter when"];
-            45 [label="Access variable R|<local>/flag|"];
-            46 [label="Check not null: R|<local>/flag|!!"];
+            48 [label="Enter when"];
+            49 [label="Access variable R|<local>/flag|"];
+            50 [label="Check not null: R|<local>/flag|!!"];
             subgraph cluster_13 {
                 color=blue
-                47 [label="Enter when branch condition "];
-                48 [label="Access variable R|/SomeEnum.A1|"];
-                49 [label="Operator =="];
-                50 [label="Exit when branch condition"];
+                51 [label="Enter when branch condition "];
+                52 [label="Access qualifier /SomeEnum"];
+                53 [label="Access variable R|/SomeEnum.A1|"];
+                54 [label="Operator =="];
+                55 [label="Exit when branch condition"];
             }
             subgraph cluster_14 {
                 color=blue
-                51 [label="Enter when branch condition "];
-                52 [label="Access variable R|/SomeEnum.A2|"];
-                53 [label="Operator =="];
-                54 [label="Exit when branch condition"];
+                56 [label="Enter when branch condition "];
+                57 [label="Access qualifier /SomeEnum"];
+                58 [label="Access variable R|/SomeEnum.A2|"];
+                59 [label="Operator =="];
+                60 [label="Exit when branch condition"];
             }
-            55 [label="Enter when branch result"];
+            61 [label="Enter when branch result"];
             subgraph cluster_15 {
                 color=blue
-                56 [label="Enter block"];
-                57 [label="Function call: R|/B.B|()"];
-                58 [label="Exit block"];
+                62 [label="Enter block"];
+                63 [label="Function call: R|/B.B|()"];
+                64 [label="Exit block"];
             }
-            59 [label="Exit when branch result"];
-            60 [label="Enter when branch result"];
+            65 [label="Exit when branch result"];
+            66 [label="Enter when branch result"];
             subgraph cluster_16 {
                 color=blue
-                61 [label="Enter block"];
-                62 [label="Function call: R|/B.B|()"];
-                63 [label="Exit block"];
+                67 [label="Enter block"];
+                68 [label="Function call: R|/B.B|()"];
+                69 [label="Exit block"];
             }
-            64 [label="Exit when branch result"];
-            65 [label="Exit when"];
+            70 [label="Exit when branch result"];
+            71 [label="Exit when"];
         }
-        66 [label="Variable declaration: lval b: R|B|"];
-        67 [label="Access variable R|<local>/b|"];
-        68 [label="Function call: R|/takeB|(...)"];
-        69 [label="Exit function test_2" style="filled" fillcolor=red];
+        72 [label="Variable declaration: lval b: R|B|"];
+        73 [label="Access variable R|<local>/b|"];
+        74 [label="Function call: R|/takeB|(...)"];
+        75 [label="Exit function test_2" style="filled" fillcolor=red];
     }
 
-    41 -> {42};
-    42 -> {43};
-    43 -> {44};
     44 -> {45};
     45 -> {46};
     46 -> {47};
     47 -> {48};
     48 -> {49};
     49 -> {50};
-    50 -> {60 51};
+    50 -> {51};
     51 -> {52};
     52 -> {53};
     53 -> {54};
     54 -> {55};
-    55 -> {56};
+    55 -> {66 56};
     56 -> {57};
     57 -> {58};
     58 -> {59};
-    59 -> {65};
+    59 -> {60};
     60 -> {61};
     61 -> {62};
     62 -> {63};
     63 -> {64};
     64 -> {65};
-    65 -> {66};
+    65 -> {71};
     66 -> {67};
     67 -> {68};
     68 -> {69};
+    69 -> {70};
+    70 -> {71};
+    71 -> {72};
+    72 -> {73};
+    73 -> {74};
+    74 -> {75};
 
     subgraph cluster_17 {
         color=red
-        70 [label="Enter function test_3" style="filled" fillcolor=red];
-        71 [label="Access variable R|/SomeEnum.A1|"];
-        72 [label="Variable declaration: lval flag: R|SomeEnum|"];
+        76 [label="Enter function test_3" style="filled" fillcolor=red];
+        77 [label="Access qualifier /SomeEnum"];
+        78 [label="Access variable R|/SomeEnum.A1|"];
+        79 [label="Variable declaration: lval flag: R|SomeEnum|"];
         subgraph cluster_18 {
             color=blue
-            73 [label="Enter when"];
-            74 [label="Access variable R|<local>/flag|"];
+            80 [label="Enter when"];
+            81 [label="Access variable R|<local>/flag|"];
             subgraph cluster_19 {
                 color=blue
-                75 [label="Enter when branch condition "];
-                76 [label="Access variable R|/SomeEnum.A1|"];
-                77 [label="Operator =="];
-                78 [label="Exit when branch condition"];
+                82 [label="Enter when branch condition "];
+                83 [label="Access qualifier /SomeEnum"];
+                84 [label="Access variable R|/SomeEnum.A1|"];
+                85 [label="Operator =="];
+                86 [label="Exit when branch condition"];
             }
             subgraph cluster_20 {
                 color=blue
-                79 [label="Enter when branch condition "];
-                80 [label="Access variable R|/SomeEnum.A2|"];
-                81 [label="Operator =="];
-                82 [label="Exit when branch condition"];
+                87 [label="Enter when branch condition "];
+                88 [label="Access qualifier /SomeEnum"];
+                89 [label="Access variable R|/SomeEnum.A2|"];
+                90 [label="Operator =="];
+                91 [label="Exit when branch condition"];
             }
-            83 [label="Enter when branch result"];
+            92 [label="Enter when branch result"];
             subgraph cluster_21 {
                 color=blue
-                84 [label="Enter block"];
-                85 [label="Function call: R|/B.B|()"];
-                86 [label="Exit block"];
+                93 [label="Enter block"];
+                94 [label="Function call: R|/B.B|()"];
+                95 [label="Exit block"];
             }
-            87 [label="Exit when branch result"];
-            88 [label="Enter when branch result"];
+            96 [label="Exit when branch result"];
+            97 [label="Enter when branch result"];
             subgraph cluster_22 {
                 color=blue
-                89 [label="Enter block"];
-                90 [label="Function call: R|/B.B|()"];
-                91 [label="Exit block"];
+                98 [label="Enter block"];
+                99 [label="Function call: R|/B.B|()"];
+                100 [label="Exit block"];
             }
-            92 [label="Exit when branch result"];
-            93 [label="Exit when"];
+            101 [label="Exit when branch result"];
+            102 [label="Exit when"];
         }
-        94 [label="Variable declaration: lval b: R|B|"];
-        95 [label="Access variable R|<local>/b|"];
-        96 [label="Function call: R|/takeB|(...)"];
-        97 [label="Exit function test_3" style="filled" fillcolor=red];
+        103 [label="Variable declaration: lval b: R|B|"];
+        104 [label="Access variable R|<local>/b|"];
+        105 [label="Function call: R|/takeB|(...)"];
+        106 [label="Exit function test_3" style="filled" fillcolor=red];
     }
 
-    70 -> {71};
-    71 -> {72};
-    72 -> {73};
-    73 -> {74};
-    74 -> {75};
-    75 -> {76};
     76 -> {77};
     77 -> {78};
-    78 -> {88 79};
+    78 -> {79};
     79 -> {80};
     80 -> {81};
     81 -> {82};
@@ -264,8 +273,8 @@ digraph exhaustiveWhenAndDNNType_kt {
     83 -> {84};
     84 -> {85};
     85 -> {86};
-    86 -> {87};
-    87 -> {93};
+    86 -> {97 87};
+    87 -> {88};
     88 -> {89};
     89 -> {90};
     90 -> {91};
@@ -274,6 +283,15 @@ digraph exhaustiveWhenAndDNNType_kt {
     93 -> {94};
     94 -> {95};
     95 -> {96};
-    96 -> {97};
+    96 -> {102};
+    97 -> {98};
+    98 -> {99};
+    99 -> {100};
+    100 -> {101};
+    101 -> {102};
+    102 -> {103};
+    103 -> {104};
+    104 -> {105};
+    105 -> {106};
 
 }

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsTestGenerated.java

@@ -606,6 +606,11 @@ public class FirDiagnosticsTestGenerated extends AbstractFirDiagnosticsTest {
             runTest("compiler/fir/resolve/testData/resolve/cfg/lambdaAsReturnOfLambda.kt");
         }
 
+        @TestMetadata("lambdaReturningObject.kt")
+        public void testLambdaReturningObject() throws Exception {
+            runTest("compiler/fir/resolve/testData/resolve/cfg/lambdaReturningObject.kt");
+        }
+
         @TestMetadata("lambdas.kt")
         public void testLambdas() throws Exception {
             runTest("compiler/fir/resolve/testData/resolve/cfg/lambdas.kt");

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithLightTreeTestGenerated.java

@@ -606,6 +606,11 @@ public class FirDiagnosticsWithLightTreeTestGenerated extends AbstractFirDiagnos
             runTest("compiler/fir/resolve/testData/resolve/cfg/lambdaAsReturnOfLambda.kt");
         }
 
+        @TestMetadata("lambdaReturningObject.kt")
+        public void testLambdaReturningObject() throws Exception {
+            runTest("compiler/fir/resolve/testData/resolve/cfg/lambdaReturningObject.kt");
+        }
+
         @TestMetadata("lambdas.kt")
         public void testLambdas() throws Exception {
             runTest("compiler/fir/resolve/testData/resolve/cfg/lambdas.kt");