[Analysis API] Provide API for getting KtTypeAliasSymbol by ClassId

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

@@ -10,11 +10,13 @@ import org.jetbrains.kotlin.analysis.api.descriptors.components.base.Fe10KtAnaly
 import org.jetbrains.kotlin.analysis.api.descriptors.symbols.KtFe10FileSymbol
 import org.jetbrains.kotlin.analysis.api.descriptors.symbols.KtFe10PackageSymbol
 import org.jetbrains.kotlin.analysis.api.descriptors.symbols.descriptorBased.base.toKtClassSymbol
+import org.jetbrains.kotlin.analysis.api.descriptors.symbols.descriptorBased.base.toKtClassifierSymbol
 import org.jetbrains.kotlin.analysis.api.descriptors.symbols.descriptorBased.base.toKtSymbol
 import org.jetbrains.kotlin.analysis.api.descriptors.symbols.psiBased.*
 import org.jetbrains.kotlin.analysis.api.lifetime.KtLifetimeToken
 import org.jetbrains.kotlin.analysis.api.symbols.*
 import org.jetbrains.kotlin.descriptors.findClassAcrossModuleDependencies
+import org.jetbrains.kotlin.descriptors.findTypeAliasAcrossModuleDependencies
 import org.jetbrains.kotlin.descriptors.isEmpty
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
@@ -122,6 +124,11 @@ internal class KtFe10SymbolProvider(
         return descriptor.toKtClassSymbol(analysisContext)
     }
 
+    override fun getTypeAliasByClassId(classId: ClassId): KtTypeAliasSymbol? {
+        val descriptor = analysisContext.resolveSession.moduleDescriptor.findTypeAliasAcrossModuleDependencies(classId) ?: return null
+        return descriptor.toKtClassifierSymbol(analysisContext) as? KtTypeAliasSymbol
+    }
+
     override fun getTopLevelCallableSymbols(packageFqName: FqName, name: Name): Sequence<KtCallableSymbol> {
         val packageViewDescriptor = analysisContext.resolveSession.moduleDescriptor.getPackage(packageFqName)
         return packageViewDescriptor.memberScope.getContributedDescriptors(DescriptorKindFilter.ALL, nameFilter = { it == name })

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

@@ -161,6 +161,11 @@ internal class KtFirSymbolProvider(
         return firSymbolBuilder.classifierBuilder.buildNamedClassOrObjectSymbol(symbol)
     }
 
+    override fun getTypeAliasByClassId(classId: ClassId): KtTypeAliasSymbol? {
+        val symbol = firSymbolProvider.getClassLikeSymbolByClassId(classId) as? FirTypeAliasSymbol ?: return null
+        return firSymbolBuilder.classifierBuilder.buildTypeAliasSymbol(symbol)
+    }
+
     override fun getTopLevelCallableSymbols(packageFqName: FqName, name: Name): Sequence<KtCallableSymbol> {
         val firs = firSymbolProvider.getTopLevelCallableSymbols(packageFqName, name)
         return firs.asSequence().map { firSymbol ->

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

@@ -55,6 +55,8 @@ public abstract class KtSymbolProvider : KtAnalysisSessionComponent() {
 
     public abstract fun getClassOrObjectSymbolByClassId(classId: ClassId): KtClassOrObjectSymbol?
 
+    public abstract fun getTypeAliasByClassId(classId: ClassId): KtTypeAliasSymbol?
+
     public abstract fun getTopLevelCallableSymbols(packageFqName: FqName, name: Name): Sequence<KtCallableSymbol>
 
     @Suppress("PropertyName")
@@ -142,6 +144,12 @@ public interface KtSymbolProviderMixIn : KtAnalysisSessionMixIn {
     public fun getClassOrObjectSymbolByClassId(classId: ClassId): KtClassOrObjectSymbol? =
         withValidityAssertion { analysisSession.symbolProvider.getClassOrObjectSymbolByClassId(classId) }
 
+    /**
+     * @return [KtTypeAliasSymbol] with specified [classId] or `null` in case such symbol is not found
+     */
+    public fun getTypeAliasByClassId(classId: ClassId): KtTypeAliasSymbol? =
+        withValidityAssertion { analysisSession.symbolProvider.getTypeAliasByClassId(classId) }
+
     /**
      * @return list of top-level functions and properties which are visible from current use-site module
      *