From 9619c695b794b14274e2cabc63bb42a4d7b9b9b0 Mon Sep 17 00:00:00 2001
From: Yan Zhulanow <yan.zhulanow@jetbrains.com>
Date: Fri, 20 Jan 2023 16:39:18 +0900
Subject: [PATCH] [LL API] Support nested type aliases in file-based
 declaration provider

---
 .../structure/FileBasedKotlinDeclarationProvider.kt        | 3 +--
 .../fileBasedDeclarationProvider/nestedTypeAlias.kt        | 7 +++++++
 .../FileBasedKotlinDeclarationProviderTestGenerated.java   | 6 ++++++
 3 files changed, 14 insertions(+), 2 deletions(-)
 create mode 100644 analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/nestedTypeAlias.kt

diff --git a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/FileBasedKotlinDeclarationProvider.kt b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/FileBasedKotlinDeclarationProvider.kt
index e6bee69f823..c7a99aa3716 100644
--- a/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/FileBasedKotlinDeclarationProvider.kt
+++ b/analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/FileBasedKotlinDeclarationProvider.kt
@@ -65,8 +65,7 @@ internal class FileBasedKotlinDeclarationProvider(private val kotlinFile: KtFile
     }
 
     override fun getAllTypeAliasesByClassId(classId: ClassId): Collection<KtTypeAlias> {
-        val name = classId.relativeClassName.pathSegments().singleOrNull() ?: return emptyList()
-        return getTopLevelDeclarations(classId.packageFqName, name)
+        return getClassLikeDeclarationsByClassId(classId).filterIsInstance<KtTypeAlias>().toList()
     }
 
     override fun getTopLevelKotlinClassLikeDeclarationNamesInPackage(packageFqName: FqName): Set<Name> {
diff --git a/analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/nestedTypeAlias.kt b/analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/nestedTypeAlias.kt
new file mode 100644
index 00000000000..52f8df84002
--- /dev/null
+++ b/analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/nestedTypeAlias.kt
@@ -0,0 +1,7 @@
+// TYPE_ALIAS: test/Foo.Bar
+
+package test
+
+class Foo {
+    typealias Bar = Foo
+}
\ No newline at end of file
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/FileBasedKotlinDeclarationProviderTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/FileBasedKotlinDeclarationProviderTestGenerated.java
index 7f7e44998d1..93e242d4ec8 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/FileBasedKotlinDeclarationProviderTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/FileBasedKotlinDeclarationProviderTestGenerated.java
@@ -36,6 +36,12 @@ public class FileBasedKotlinDeclarationProviderTestGenerated extends AbstractFil
         runTest("analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/local.kt");
     }
 
+    @Test
+    @TestMetadata("nestedTypeAlias.kt")
+    public void testNestedTypeAlias() throws Exception {
+        runTest("analysis/low-level-api-fir/testdata/fileBasedDeclarationProvider/nestedTypeAlias.kt");
+    }
+
     @Test
     @TestMetadata("sameNames.kt")
     public void testSameNames() throws Exception {