From 5afebb4e789607109ffc18942f747b73fbdb3a9d Mon Sep 17 00:00:00 2001
From: "Denis.Zharkov" <denis.zharkov@jetbrains.com>
Date: Thu, 14 Jan 2021 16:26:35 +0300
Subject: [PATCH] FIR: Transform synthetic calls children even without
 incomplete candidate

It might be necessary for cases like
run @l1{
   run {
      if (...) return@l1 1
   }
}

"if" is a synthetic call, but without candidate since there's just one branch
But return@l1 1 is incomplete because it's resolved in dependent context
and "1" is hang incomplete integer literal
---
 .../FirCallCompletionResultsWriterTransformer.kt      | 11 +++++++++--
 .../tests/inference/regressions/kt36342_2.fir.kt      |  2 +-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirCallCompletionResultsWriterTransformer.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirCallCompletionResultsWriterTransformer.kt
index 63e080d5868..e801a3062b0 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirCallCompletionResultsWriterTransformer.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirCallCompletionResultsWriterTransformer.kt
@@ -534,9 +534,16 @@ class FirCallCompletionResultsWriterTransformer(
         syntheticCall: D,
         data: ExpectedArgumentType?,
     ): CompositeTransformResult<FirStatement> where D : FirResolvable, D : FirExpression {
-        val calleeReference = syntheticCall.calleeReference as? FirNamedReferenceWithCandidate ?: return syntheticCall.compose()
+        val calleeReference = syntheticCall.calleeReference as? FirNamedReferenceWithCandidate
+        val declaration = calleeReference?.candidate?.symbol?.fir as? FirSimpleFunction
 
-        val declaration = calleeReference.candidate.symbol.fir as? FirSimpleFunction ?: return syntheticCall.compose()
+        if (calleeReference == null || declaration == null) {
+            syntheticCall.transformChildren(
+                this,
+                data = data?.getExpectedType(syntheticCall)?.toExpectedType() ?: syntheticCall.typeRef.coneType.toExpectedType()
+            )
+            return syntheticCall.compose()
+        }
 
         val typeRef = typeCalculator.tryCalculateReturnType(declaration)
         syntheticCall.replaceTypeRefWithSubstituted(calleeReference, typeRef)
diff --git a/compiler/testData/diagnostics/tests/inference/regressions/kt36342_2.fir.kt b/compiler/testData/diagnostics/tests/inference/regressions/kt36342_2.fir.kt
index 4657de5aa65..5e8254c4013 100644
--- a/compiler/testData/diagnostics/tests/inference/regressions/kt36342_2.fir.kt
+++ b/compiler/testData/diagnostics/tests/inference/regressions/kt36342_2.fir.kt
@@ -5,7 +5,7 @@ fun <M> materialize(): M = TODO()
 
 fun test(b: Boolean) {
     <!INAPPLICABLE_CANDIDATE!>id<!>(if (b) {
-        id(<!UNRESOLVED_REFERENCE!>unresolved<!>)
+        <!INAPPLICABLE_CANDIDATE!>id<!>(<!UNRESOLVED_REFERENCE!>unresolved<!>)
     } else {
         id(
             materialize()