use unique_ptr for ExifData

[neheb]

Avoids needing a definition in header.

[Copilot]

Pull Request Overview

This PR refactors the TiffEncoder class to use std::unique_ptr for managing ExifData, eliminating the need for the ExifData definition in the header file.

• Changes ExifData member from value type to std::unique_ptr
• Removes the exif.hpp include from the header file
• Updates all ExifData usage to use pointer dereference syntax

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/tiffvisitor_int.hpp	Removes exif.hpp include and changes ExifData member to unique_ptr
src/tiffvisitor_int.cpp	Updates constructor and all methods to use pointer dereference for ExifData access

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[neheb]

Incredible. Only clang-cl errors on what I think would be an error everywhere. Incredible.

[neheb]

reran CI.

[kevinbackhouse]

What's the benefit of this change? Is it just so that you can delete #include "exif.hpp"? But it introduces a new risk that exifData_ could be null, doesn't it?

[neheb]

It's never NULL.

I can't use a reference here as it must be a copy.

edit: looking at the code, these references probably need const/removal. Will post an alternate PR.