[Analysis API] Treat inapplicable declarations safely (KTIJ-23458)

Make 'getClassOrObjectSymbol()' and 'getNamedClassOrObjectSymbol()'
return 'null' for inapplicable PSI declarations.

analysis/analysis-api-fe10/src/org/jetbrains/kotlin/analysis/api/descriptors/components/KtFe10SymbolProvider.kt

@@ -87,8 +87,10 @@ internal class KtFe10SymbolProvider(
         return KtFe10PsiAnonymousObjectSymbol(psi.objectDeclaration, analysisContext)
     }
 
-    override fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol {
-        return if (psi is KtObjectDeclaration && psi.isObjectLiteral()) {
+    override fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol? {
+        return if (psi is KtEnumEntry) {
+            null
+        } else if (psi is KtObjectDeclaration && psi.isObjectLiteral()) {
             KtFe10PsiAnonymousObjectSymbol(psi, analysisContext)
         } else {
             KtFe10PsiNamedClassOrObjectSymbol(psi, analysisContext)

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/symbols/KtFirSymbolProvider.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.analysis.utils.errors.buildErrorWithAttachment
 import org.jetbrains.kotlin.analysis.utils.errors.withPsiEntry
+import org.jetbrains.kotlin.psi.psiUtil.isObjectLiteral
 
 internal class KtFirSymbolProvider(
     override val analysisSession: KtFirAnalysisSession,
@@ -113,16 +114,22 @@ internal class KtFirSymbolProvider(
         )
     }
 
-    override fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol {
-        val firClass = psi.resolveToFirClassLikeSymbol()
-        return firSymbolBuilder.classifierBuilder.buildClassOrObjectSymbol(firClass)
+    override fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol? {
+        if (psi is KtEnumEntry) {
+            return null
+        }
+
+        val firSymbol = psi.resolveToFirClassLikeSymbol()
+        return firSymbolBuilder.classifierBuilder.buildClassOrObjectSymbol(firSymbol)
     }
 
     override fun getNamedClassOrObjectSymbol(psi: KtClassOrObject): KtNamedClassOrObjectSymbol? {
-        require(psi !is KtObjectDeclaration || psi.parent !is KtObjectLiteralExpression)
-        // A KtClassOrObject may also map to an FirEnumEntry. Hence, we need to return null in this case.
-        if (psi is KtEnumEntry) return null
-        return firSymbolBuilder.classifierBuilder.buildNamedClassOrObjectSymbol(psi.resolveToFirClassLikeSymbol() as FirRegularClassSymbol)
+        if (psi is KtEnumEntry || psi.isObjectLiteral()) {
+            return null
+        }
+
+        val firSymbol = psi.resolveToFirClassLikeSymbol() as FirRegularClassSymbol
+        return firSymbolBuilder.classifierBuilder.buildNamedClassOrObjectSymbol(firSymbol)
     }
 
     private fun KtClassOrObject.resolveToFirClassLikeSymbol(): FirClassSymbol<*> {

analysis/analysis-api-impl-base/tests/org/jetbrains/kotlin/analysis/api/impl/base/test/cases/components/containingDeclarationProvider/AbstractContainingDeclarationProviderByDelegatedMemberScopeTest.kt

@@ -19,7 +19,7 @@ abstract class AbstractContainingDeclarationProviderByDelegatedMemberScopeTest :
         val declaration = testServices.expressionMarkerProvider.getElementOfTypeAtCaret<KtClassOrObject>(ktFile)
 
         val memberToContainingClass = analyseForTest(declaration) {
-            val symbol = declaration.getClassOrObjectSymbol()
+            val symbol = declaration.getClassOrObjectSymbol()!!
             renderScopeWithParentDeclarations(symbol.getDelegatedMemberScope())
         }
 

analysis/analysis-api-impl-base/tests/org/jetbrains/kotlin/analysis/api/impl/base/test/cases/components/containingDeclarationProvider/AbstractContainingDeclarationProviderByMemberScopeTest.kt

@@ -24,7 +24,7 @@ abstract class AbstractContainingDeclarationProviderByMemberScopeTest : Abstract
         val declaration = testServices.expressionMarkerProvider.getElementOfTypeAtCaret<KtClassOrObject>(ktFile)
 
         val memberToContainingClass = analyseForTest(declaration) {
-            val symbol = declaration.getClassOrObjectSymbol()
+            val symbol = declaration.getClassOrObjectSymbol()!!
             renderScopeWithParentDeclarations(symbol.getMemberScope())
         }
 

analysis/analysis-api-impl-base/tests/org/jetbrains/kotlin/analysis/api/impl/base/test/cases/components/symbolDeclarationOverridesProvider/AbstractIsSubclassOfTest.kt

@@ -21,8 +21,8 @@ abstract class AbstractIsSubclassOfTest : AbstractAnalysisApiBasedSingleModuleTe
 
         val actual = executeOnPooledThreadInReadAction {
             analyseForTest(subClass) {
-                val subClassSymbol = subClass.getClassOrObjectSymbol()
-                val superClassSymbol = superClass.getClassOrObjectSymbol()
+                val subClassSymbol = subClass.getClassOrObjectSymbol()!!
+                val superClassSymbol = superClass.getClassOrObjectSymbol()!!
 
                 val isSubClass = subClassSymbol.isSubClassOf(superClassSymbol)
                 val isDirectSubClass = subClassSymbol.isDirectSubClassOf(superClassSymbol)

analysis/analysis-api/src/org/jetbrains/kotlin/analysis/api/symbols/KtSymbolProvider.kt

@@ -26,7 +26,7 @@ public abstract class KtSymbolProvider : KtAnalysisSessionComponent() {
         is KtProperty -> getVariableSymbol(psi)
         is KtClassOrObject -> {
             val literalExpression = (psi as? KtObjectDeclaration)?.parent as? KtObjectLiteralExpression
-            literalExpression?.let(::getAnonymousObjectSymbol) ?: getClassOrObjectSymbol(psi)
+            literalExpression?.let(::getAnonymousObjectSymbol) ?: getClassOrObjectSymbol(psi)!!
         }
         is KtPropertyAccessor -> getPropertyAccessorSymbol(psi)
         is KtClassInitializer -> getClassInitializerSymbol(psi)
@@ -45,7 +45,7 @@ public abstract class KtSymbolProvider : KtAnalysisSessionComponent() {
     public abstract fun getAnonymousFunctionSymbol(psi: KtFunctionLiteral): KtAnonymousFunctionSymbol
     public abstract fun getVariableSymbol(psi: KtProperty): KtVariableSymbol
     public abstract fun getAnonymousObjectSymbol(psi: KtObjectLiteralExpression): KtAnonymousObjectSymbol
-    public abstract fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol
+    public abstract fun getClassOrObjectSymbol(psi: KtClassOrObject): KtClassOrObjectSymbol?
     public abstract fun getNamedClassOrObjectSymbol(psi: KtClassOrObject): KtNamedClassOrObjectSymbol?
     public abstract fun getPropertyAccessorSymbol(psi: KtPropertyAccessor): KtPropertyAccessorSymbol
     public abstract fun getClassInitializerSymbol(psi: KtClassInitializer): KtClassInitializerSymbol
@@ -115,10 +115,11 @@ public interface KtSymbolProviderMixIn : KtAnalysisSessionMixIn {
     public fun KtObjectLiteralExpression.getAnonymousObjectSymbol(): KtAnonymousObjectSymbol =
         withValidityAssertion { analysisSession.symbolProvider.getAnonymousObjectSymbol(this) }
 
-    public fun KtClassOrObject.getClassOrObjectSymbol(): KtClassOrObjectSymbol =
+    /** Returns a symbol for a given [KtClassOrObject]. Returns `null` for `KtEnumEntry` declarations. */
+    public fun KtClassOrObject.getClassOrObjectSymbol(): KtClassOrObjectSymbol? =
         withValidityAssertion { analysisSession.symbolProvider.getClassOrObjectSymbol(this) }
 
-    /** Gets the corresponding class or object symbol or null if the given [KtClassOrObject] is an enum entry. */
+    /** Returns a symbol for a given named [KtClassOrObject]. Returns `null` for `KtEnumEntry` declarations and object literals. */
     public fun KtClassOrObject.getNamedClassOrObjectSymbol(): KtNamedClassOrObjectSymbol? =
         withValidityAssertion { analysisSession.symbolProvider.getNamedClassOrObjectSymbol(this) }
 

analysis/symbol-light-classes/src/org/jetbrains/kotlin/light/classes/symbol/classes/symbolLightClassUtils.kt

@@ -69,7 +69,7 @@ internal fun createSymbolLightClassNoCache(classOrObject: KtClassOrObject): KtLi
 
         else -> {
             analyzeForLightClasses(classOrObject) {
-                classOrObject.getClassOrObjectSymbol().createLightClassNoCache(classOrObject.manager)
+                classOrObject.getClassOrObjectSymbol()?.createLightClassNoCache(classOrObject.manager)
             }
         }
     }
@@ -480,7 +480,7 @@ internal fun KtClassOrObject.checkIsInheritor(superClassOrigin: KtClassOrObject,
         return false
     }
 
-    val superClassSymbol = superClassOrigin.getClassOrObjectSymbol()
+    val superClassSymbol = superClassOrigin.getClassOrObjectSymbol() ?: return false
 
     when (this) {
         is KtEnumEntry -> {
@@ -498,7 +498,7 @@ internal fun KtClassOrObject.checkIsInheritor(superClassOrigin: KtClassOrObject,
         else -> {
             val subClassSymbol = this.getClassOrObjectSymbol()
 
-            if (subClassSymbol == superClassSymbol) return false
+            if (subClassSymbol == null || subClassSymbol == superClassSymbol) return false
 
             return if (checkDeep) {
                 subClassSymbol.isSubClassOf(superClassSymbol)