SG-39031 comment updated for outdated reference

[eduardoChaucaGallegos]

Description

This pull request makes a minor update to the post_qt_init method in engine.py to clarify the behavior of QTextCodec.setCodecForCStrings() when using PySide2/PySide6. The comment now explains that the method is effectively a no-op on these versions due to a patched stub. No functional code changes were made.

[staceyoue]

This pull request makes a minor update to the post_qt_init method in engine.py to clarify the behavior of QTextCodec.setCodecForCStrings() when using PySide2/PySide6. The comment now explains that the method is effectively a no-op on these versions due to a patched stub. No functional code changes were made.

@eduardoChaucaGallegos can you explain this a little more why we're removing this? Is it patched in tk-core? If so, can you point to where this is patched and is effectively and no-op. Thanks

[eduardoChaucaGallegos]

This pull request makes a minor update to the post_qt_init method in engine.py to clarify the behavior of QTextCodec.setCodecForCStrings() when using PySide2/PySide6. The comment now explains that the method is effectively a no-op on these versions due to a patched stub. No functional code changes were made.

@eduardoChaucaGallegos can you explain this a little more why we're removing this? Is it patched in tk-core? If so, can you point to where this is patched and is effectively and no-op. Thanks

@staceyoue, sure! The reason we're removing this code is that QTextCodec.setCodecForCStrings() was deprecated and removed in Qt 5. According to the official Qt documentation on source breaks:

Reference: https://doc.qt.io/archives/qt-5.15/sourcebreaks.html#changes-to-qtextcodec

"The QTextCodec::codecForCStrings() and QTextCodec::setCodecForCStrings() functions have been removed. This is because Qt now assumes that all C-strings are encoded in UTF-8."

In Qt 5 and later (which includes PySide2 and PySide6), all strings are UTF-8 by default, so explicitly setting the codec is no longer necessary or supported.

Regarding the patch in tk-core, yes, there is a patcher that handles this: https://github.com/shotgunsoftware/tk-core/blob/master/python/tank/util/pyside2_patcher.py#L76

As you can see in the code, the patched function effectively does nothing. This patcher will be addressed and removed in a separate ticket where we'll analyze all the necessary considerations to avoid any backward compatibility issues.

Since we're using PySide2/Qt5+, these methods don't exist anymore, and the original code in our engine was redundant because:

It's trying to call methods that don't exist in PySide2/Qt5+
Qt5+ already handles UTF-8 encoding by default
Therefore, it's safe to remove this code from our engine.

@carlos-villavicencio-adsk @julien-lang

[staceyoue]

This pull request makes a minor update to the post_qt_init method in engine.py to clarify the behavior of QTextCodec.setCodecForCStrings() when using PySide2/PySide6. The comment now explains that the method is effectively a no-op on these versions due to a patched stub. No functional code changes were made.

@eduardoChaucaGallegos can you explain this a little more why we're removing this? Is it patched in tk-core? If so, can you point to where this is patched and is effectively and no-op. Thanks

@staceyoue, sure! The reason we're removing this code is that QTextCodec.setCodecForCStrings() was deprecated and removed in Qt 5. According to the official Qt documentation on source breaks:

Reference: https://doc.qt.io/archives/qt-5.15/sourcebreaks.html#changes-to-qtextcodec

"The QTextCodec::codecForCStrings() and QTextCodec::setCodecForCStrings() functions have been removed. This is because Qt now assumes that all C-strings are encoded in UTF-8."

In Qt 5 and later (which includes PySide2 and PySide6), all strings are UTF-8 by default, so explicitly setting the codec is no longer necessary or supported.

Regarding the patch in tk-core, yes, there is a patcher that handles this: https://github.com/shotgunsoftware/tk-core/blob/master/python/tank/util/pyside2_patcher.py#L76

As you can see in the code, the patched function effectively does nothing. This patcher will be addressed and removed in a separate ticket where we'll analyze all the necessary considerations to avoid any backward compatibility issues.

Since we're using PySide2/Qt5+, these methods don't exist anymore, and the original code in our engine was redundant because:

It's trying to call methods that don't exist in PySide2/Qt5+ Qt5+ already handles UTF-8 encoding by default Therefore, it's safe to remove this code from our engine.

@carlos-villavicencio-adsk @julien-lang

@eduardoChaucaGallegos ok makes sense, thanks for this level of detail