Add ParserMultiInputStream

src/Parser/Parsing/Impl/ParserMultiInputStream.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <istream>
+#include <stack>
+#include <memory>
+#include <functional>
+
+#include "Parsing/IParserLineStream.h"
+
+class ParserMultiInputStream final : public IParserLineStream
+{
+public:
+    using include_callback_t = std::function<std::unique_ptr<std::istream>(const std::string& filename)>;
+
+private:
+    class FileInfo
+    {
+    public:
+        std::unique_ptr<std::istream> m_owned_stream;
+        std::istream& m_stream;
+        std::string m_file_path;
+        int m_line_number;
+
+        FileInfo(std::unique_ptr<std::istream> stream, std::string filePath);
+        FileInfo(std::istream& stream, std::string filePath);
+    };
+
+    const include_callback_t m_include_callback;
+    std::stack<FileInfo> m_files;
+
+public:
+    ParserMultiInputStream(std::unique_ptr<std::istream> stream, std::string fileName, include_callback_t includeCallback);
+    ParserMultiInputStream(std::istream& stream, std::string fileName, include_callback_t includeCallback);
+
+    ParserLine NextLine() override;
+    bool IncludeFile(const std::string& filename) override;
+    void PopCurrentFile() override;
+    _NODISCARD bool IsOpen() const override;
+    _NODISCARD bool Eof() const override;
+};