From a52674f1813a07f914c197356cbb8f9a01e510fe Mon Sep 17 00:00:00 2001
From: Ilya Kirillov <ilya.kirillov@jetbrains.com>
Date: Thu, 31 Dec 2020 11:35:32 +0100
Subject: [PATCH] FIR: use more meaningful error messages

---
 .../src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt  | 6 ++++++
 .../resolve/calls/tower/FirInvokeResolveTowerExtension.kt   | 4 ++--
 .../fir/resolve/transformers/FirStatusResolveTransformer.kt | 4 +++-
 .../src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt   | 2 +-
 .../src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt   | 4 +++-
 5 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
index 14f6da469f7..f127007a411 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/LookupTagUtils.kt
@@ -33,6 +33,12 @@ fun ConeClassLikeLookupTag.toSymbol(useSiteSession: FirSession): FirClassLikeSym
     }
 }
 
+@OptIn(LookupTagInternals::class)
+fun ConeClassLikeLookupTag.toSymbolOrError(useSiteSession: FirSession): FirClassLikeSymbol<*> =
+    toSymbol(useSiteSession)
+        ?: error("Class symbol with classId $classId was not found")
+
+
 fun ConeClassLikeLookupTag.toFirRegularClass(session: FirSession): FirRegularClass? =
     session.firSymbolProvider.getSymbolByLookupTag(this)?.fir as? FirRegularClass
 
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/tower/FirInvokeResolveTowerExtension.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/tower/FirInvokeResolveTowerExtension.kt
index fb199e89b79..fc0138efa64 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/tower/FirInvokeResolveTowerExtension.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/tower/FirInvokeResolveTowerExtension.kt
@@ -262,8 +262,8 @@ private fun BodyResolveComponents.createExplicitReceiverForInvoke(
         is FirRegularClassSymbol -> buildResolvedQualifierForClass(symbol, sourceElement = null)
         is FirTypeAliasSymbol -> {
             val type = symbol.fir.expandedTypeRef.coneTypeUnsafe<ConeClassLikeType>().fullyExpandedType(session)
-            val expansionRegularClass = type.lookupTag.toSymbol(session)?.fir as? FirRegularClass
-            buildResolvedQualifierForClass(expansionRegularClass!!.symbol, sourceElement = symbol.fir.source)
+            val expansionRegularClassSymbol = type.lookupTag.toSymbolOrError(session)
+            buildResolvedQualifierForClass(expansionRegularClassSymbol, sourceElement = symbol.fir.source)
         }
         else -> throw AssertionError()
     }
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirStatusResolveTransformer.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirStatusResolveTransformer.kt
index 2b1f30d9246..08ba47d5a25 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirStatusResolveTransformer.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirStatusResolveTransformer.kt
@@ -393,7 +393,9 @@ abstract class AbstractFirStatusResolveTransformer(
             }
             return
         }
-        require(file != null)
+        require(file != null) {
+            "Containing file was not found for\n${regularClass.render()}"
+        }
         val symbol = regularClass.symbol
         var declarationToStart: FirDeclaration? = null
         val designation = designationMapForLocalClasses[regularClass]?.let(::listOf)?.also {
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt
index b6905baca37..169e38722e2 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt
@@ -221,7 +221,7 @@ interface ConeTypeContext : TypeSystemContext, TypeSystemOptimizationContext, Ty
             is FirAnonymousObjectSymbol -> symbol.fir.typeParameters[index].symbol.toLookupTag()
             is FirRegularClassSymbol -> symbol.fir.typeParameters[index].symbol.toLookupTag()
             is FirTypeAliasSymbol -> symbol.fir.typeParameters[index].symbol.toLookupTag()
-            else -> error("?!:12")
+            else -> error("Unexpected FirClassLikeSymbol $symbol for ${this::class}, with classId ${(this as? ConeClassLikeLookupTag)?.classId}")
         }
     }
 
diff --git a/core/compiler.common/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt b/core/compiler.common/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt
index da6799b18da..017dd9873ed 100644
--- a/core/compiler.common/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt
+++ b/core/compiler.common/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt
@@ -69,7 +69,9 @@ abstract class AbstractTypeCheckerContext : TypeSystemContext {
 
 
     fun initialize() {
-        assert(!supertypesLocked)
+        assert(!supertypesLocked) {
+            "Supertypes were locked for ${this::class}"
+        }
         supertypesLocked = true
 
         if (supertypesDeque == null) {