[Migrator] During de-serialization, remove duplicated API diff items from the store. (#9239)

Author: nkcsgexi

include/swift/IDE/APIDigesterData.h

@@ -55,6 +55,7 @@ struct APIDiffItem {
   virtual APIDiffItemKind getKind() const = 0;
   virtual StringRef getKey() const = 0;
   virtual ~APIDiffItem() = default;
+  bool operator==(const APIDiffItem &Other) const;
 };
 
 // CommonDiffItem describes how an element in SDK evolves in a way that migrator can

lib/IDE/APIDigesterData.cpp

@@ -190,6 +190,28 @@ bool swift::ide::api::NAME::classof(const APIDiffItem *D) {                    \
 }
 #include "swift/IDE/DigesterEnums.def"
 
+bool APIDiffItem::operator==(const APIDiffItem &Other) const {
+  if (getKind() != Other.getKind())
+    return false;
+  if (getKey() != Other.getKey())
+    return false;
+  switch(getKind()) {
+  case APIDiffItemKind::ADK_CommonDiffItem: {
+    auto *Left = static_cast<const CommonDiffItem*>(this);
+    auto *Right = static_cast<const CommonDiffItem*>(&Other);
+    return Left->ChildIndex == Right->ChildIndex;
+  }
+  case APIDiffItemKind::ADK_NoEscapeFuncParam: {
+    auto *Left = static_cast<const NoEscapeFuncParam*>(this);
+    auto *Right = static_cast<const NoEscapeFuncParam*>(&Other);
+    return Left->Index == Right->Index;
+  }
+  case APIDiffItemKind::ADK_TypeMemberDiffItem:
+  case APIDiffItemKind::ADK_OverloadedFuncInfo:
+    llvm_unreachable("should be handled above.");
+  }
+}
+
 namespace {
 enum class DiffItemKeyKind {
 #define DIFF_ITEM_KEY_KIND(NAME) KK_##NAME,
@@ -392,8 +414,12 @@ struct swift::ide::api::APIDiffItemStore::Implementation {
       for (auto It = Array->begin(); It != Array->end(); ++ It) {
         APIDiffItem *Item = serializeDiffItem(Allocator,
           cast<llvm::yaml::MappingNode>(&*It));
-        Data[Item->getKey()].push_back(Item);
-        AllItems.push_back(Item);
+        auto &Bag = Data[Item->getKey()];
+        if(std::find_if(Bag.begin(), Bag.end(),
+            [&](APIDiffItem* I) { return *Item == *I; }) == Bag.end()) {
+          Bag.push_back(Item);
+          AllItems.push_back(Item);
+        }
       }
     }
 

test/Migrator/API.json

@@ -270,6 +270,28 @@
     "RightComment": "",
     "ModuleName": "Cities"
   },
+  {
+    "DiffItemKind": "CommonDiffItem",
+    "NodeKind": "Function",
+    "NodeAnnotation": "WrapOptional",
+    "ChildIndex": "1",
+    "LeftUsr": "s:6Cities05ExtraA0P6blibliySQySSGSSSg_SStc1x_tF",
+    "LeftComment": "",
+    "RightUsr": "",
+    "RightComment": "",
+    "ModuleName": "Cities"
+  },
+  {
+    "DiffItemKind": "CommonDiffItem",
+    "NodeKind": "Function",
+    "NodeAnnotation": "WrapOptional",
+    "ChildIndex": "1",
+    "LeftUsr": "s:6Cities05ExtraA0P6blibliySQySSGSSSg_SStc1x_tF",
+    "LeftComment": "",
+    "RightUsr": "",
+    "RightComment": "",
+    "ModuleName": "Cities"
+  },
   {
     "DiffItemKind": "CommonDiffItem",
     "NodeKind": "Function",