From 9e697002a27c2b8b87ce062b03e91fce35a69e3f Mon Sep 17 00:00:00 2001
From: Ivy Tang <itang1@meta.com>
Date: Mon, 6 Jan 2025 15:17:10 -0800
Subject: [PATCH] Support DCG components

Summary: DCG components are just getters with `component` in the name. Patch their return when the field they're getting is annotated

Reviewed By: thezhangwei

Differential Revision: D67367181

fbshipit-source-id: 2e66dd49fd0be9f04a21d08a22228ac62f632484
---
 .../TypedefAnnoCheckerPass.cpp                | 38 ++++++++++++++-----
 .../TypedefAnnoCheckerPass.h                  |  2 +
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/opt/typedef-anno-checker/TypedefAnnoCheckerPass.cpp b/opt/typedef-anno-checker/TypedefAnnoCheckerPass.cpp
index 46dcf414769..fe7ef9cb430 100644
--- a/opt/typedef-anno-checker/TypedefAnnoCheckerPass.cpp
+++ b/opt/typedef-anno-checker/TypedefAnnoCheckerPass.cpp
@@ -31,6 +31,8 @@ constexpr const char* OBJ_REF_CLS = "Lkotlin/jvm/internal/Ref$ObjectRef;";
 constexpr const char* OBJ_REF_FIELD =
     "Lkotlin/jvm/internal/Ref$ObjectRef;.element:Ljava/lang/Object;";
 
+constexpr const char* DATA_CLASS_COMPONENT = "component";
+
 namespace {
 
 bool is_int(const type_inference::TypeEnvironment& env, reg_t reg) {
@@ -465,13 +467,20 @@ void patch_return_anno_from_get(type_inference::TypeInference& inference,
                 opcode::is_an_sget(insn->opcode()));
   auto name = caller->get_simple_deobfuscated_name();
   auto last_dollar = name.find('$');
-  if (last_dollar == std::string::npos) {
-    return;
-  }
-  last_dollar++;
-  if (!(last_dollar < name.size() && name[last_dollar] >= '0' &&
-        name[last_dollar] <= '9')) {
-    return;
+
+  // the caller methods are either data class components, named "componentX",
+  // or they're Java field accessors, which have the pattern access$XXX, where
+  // X is an integer
+  if (!boost::starts_with(caller->get_simple_deobfuscated_name(),
+                          DATA_CLASS_COMPONENT)) {
+    if (last_dollar == std::string::npos) {
+      return;
+    }
+    last_dollar++;
+    if (!(last_dollar < name.size() && name[last_dollar] >= '0' &&
+          name[last_dollar] <= '9')) {
+      return;
+    }
   }
   auto field_ref = insn->get_field();
   auto field_anno = type_inference::get_typedef_anno_from_member(
@@ -479,9 +488,7 @@ void patch_return_anno_from_get(type_inference::TypeInference& inference,
 
   if (field_anno != boost::none) {
     // Patch missing return annotations from accessed fields
-    auto res = caller->attach_annotation_set(std::make_unique<DexAnnotationSet>(
-        *field_ref->as_def()->get_anno_set()));
-    always_assert(res);
+    add_annotations(caller, field_ref->as_def()->get_anno_set());
   }
 }
 
@@ -644,6 +651,7 @@ void SynthAccessorPatcher::patch_kotlin_property_private_getter(DexMethod* m) {
 void SynthAccessorPatcher::run(const Scope& scope) {
   walk::parallel::methods(scope, [this](DexMethod* m) {
     patch_kotlin_annotated_property_getter_setter(m);
+    patch_data_class_component(m);
     if (is_synthetic_accessor(m) || is_synthetic_bridge(m)) {
       patch_accessors(m);
     }
@@ -675,6 +683,16 @@ void SynthAccessorPatcher::run(const Scope& scope) {
   });
 }
 
+void SynthAccessorPatcher::patch_data_class_component(DexMethod* m) {
+  if (type_class(m->get_class())->get_super_class()->str() ==
+          "Lcom/facebook/kotlin/compilerplugins/dataclassgenerate/superclass/"
+          "DataClassSuper;" &&
+      boost::starts_with(m->get_simple_deobfuscated_name(),
+                         DATA_CLASS_COMPONENT)) {
+    patch_accessors(m);
+  }
+}
+
 void SynthAccessorPatcher::patch_ctor_params_from_synth_cls_fields(
     DexClass* cls) {
   bool has_annotated_fields = false;
diff --git a/opt/typedef-anno-checker/TypedefAnnoCheckerPass.h b/opt/typedef-anno-checker/TypedefAnnoCheckerPass.h
index 70678597ee1..9175f00ea93 100644
--- a/opt/typedef-anno-checker/TypedefAnnoCheckerPass.h
+++ b/opt/typedef-anno-checker/TypedefAnnoCheckerPass.h
@@ -120,6 +120,8 @@ class SynthAccessorPatcher {
 
   void patch_local_var_lambda(DexMethod* method);
 
+  void patch_data_class_component(DexMethod* method);
+
   void collect_annos_from_default_method(
       DexMethod* method,
       std::vector<std::pair<src_index_t, DexAnnotationSet&>>&