Implement basic transformer tests (#689)

unittests/util/FakeFetchResponse.h

@@ -20,6 +20,119 @@
 #pragma once
 
 #include <cstddef>
+#include <string>
+#include <vector>
+
+class FakeBook
+{
+    std::string base_;
+    std::string first_;
+
+public:
+    std::string*
+    mutable_first_book()
+    {
+        return &first_;
+    }
+
+    std::string
+    book_base() const
+    {
+        return base_;
+    }
+
+    std::string*
+    mutable_book_base()
+    {
+        return &base_;
+    }
+};
+
+class FakeBookSuccessors
+{
+    std::vector<FakeBook> books_;
+
+public:
+    auto
+    begin()
+    {
+        return books_.begin();
+    }
+
+    auto
+    end()
+    {
+        return books_.end();
+    }
+};
+
+class FakeLedgerObject
+{
+public:
+    enum ModType : int { MODIFIED, DELETED };
+
+private:
+    std::string key_;
+    std::string data_;
+    std::string predecessor_;
+    std::string successor_;
+    ModType mod_ = MODIFIED;
+
+public:
+    ModType
+    mod_type() const
+    {
+        return mod_;
+    }
+
+    std::string
+    key() const
+    {
+        return key_;
+    }
+
+    std::string*
+    mutable_key()
+    {
+        return &key_;
+    }
+
+    std::string
+    data() const
+    {
+        return data_;
+    }
+
+    std::string*
+    mutable_data()
+    {
+        return &data_;
+    }
+
+    std::string*
+    mutable_predecessor()
+    {
+        return &predecessor_;
+    }
+
+    std::string*
+    mutable_successor()
+    {
+        return &successor_;
+    }
+};
+
+class FakeLedgerObjects
+{
+    std::vector<FakeLedgerObject> objects;
+
+public:
+    std::vector<FakeLedgerObject>*
+    mutable_objects()
+    {
+        return &objects;
+    }
+};
 
 class FakeTransactionsList
 {
@@ -33,11 +146,33 @@ public:
     }
 };
 
+class FakeObjectsList
+{
+    std::size_t size_ = 0;
+
+public:
+    std::size_t
+    objects_size()
+    {
+        return size_;
+    }
+};
+
 struct FakeFetchResponse
 {
     uint32_t id;
+    bool objectNeighborsIncluded;
+    FakeLedgerObjects ledgerObjects;
+    std::string ledgerHeader;
+    FakeBookSuccessors bookSuccessors;
 
-    FakeFetchResponse(uint32_t id = 0) : id{id}
+    FakeFetchResponse(uint32_t id = 0, bool objectNeighborsIncluded = false)
+        : id{id}, objectNeighborsIncluded{objectNeighborsIncluded}
+    {
+    }
+
+    FakeFetchResponse(std::string blob, uint32_t id = 0, bool objectNeighborsIncluded = false)
+        : id{id}, objectNeighborsIncluded{objectNeighborsIncluded}, ledgerHeader{blob}
     {
     }
 
@@ -52,4 +187,40 @@ struct FakeFetchResponse
     {
         return {};
     }
+
+    FakeObjectsList
+    ledger_objects() const
+    {
+        return {};
+    }
+
+    bool
+    object_neighbors_included() const
+    {
+        return objectNeighborsIncluded;
+    }
+
+    FakeLedgerObjects*
+    mutable_ledger_objects()
+    {
+        return &ledgerObjects;
+    }
+
+    std::string
+    ledger_header() const
+    {
+        return ledgerHeader;
+    }
+
+    std::string*
+    mutable_ledger_header()
+    {
+        return &ledgerHeader;
+    }
+
+    FakeBookSuccessors*
+    mutable_book_successors()
+    {
+        return &bookSuccessors;
+    }
 };