correctly migrate old settings

[3nids]

by not checking if the setting already exist

fixes #53321

in the migration of connection, if the new connection didn't exist yet, then the former code was not reaching the part where the old key was deleted. Thus at closing QGIS, the old connection is still there and when reopening, the connection would be migrated again (while deleted in former session).

[3nids]

@nyalldawson slightly related to this https://github.com/qgis/QGIS/pull/55548/files?w=1#r1505720821

[github-actions]

🪟 Windows builds ready!

Windows builds of this PR are available for testing here. Debug symbols for this build are available here.

(Built from commit 27dc2d3)

[agiudiceandrea]

The issue also affects QGIS 3.34.

[qgis-bot]

The backport to release-3_34 failed:

The process '/usr/bin/git' failed with exit code 1

stderr

error: could not apply 45d3b4d376e... correctly migrate old settings
hint: After resolving the conflicts, mark them with
hint: "git add/rm <pathspec>", then run
hint: "git cherry-pick --continue".
hint: You can instead skip this commit with "git cherry-pick --skip".
hint: To abort and get back to the state before "git cherry-pick",
hint: run "git cherry-pick --abort".

stdout

Auto-merging src/core/settings/qgssettingsentry.cpp
CONFLICT (content): Merge conflict in src/core/settings/qgssettingsentry.cpp

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-release-3_34 release-3_34
# Navigate to the new working tree
cd .worktrees/backport-release-3_34
# Create a new branch
git switch --create backport-56586-to-release-3_34
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick 45d3b4d376e105700e881078a7582a188dbcfcb7,b80a49f82e824a7579ae38c6d6588b3226858ace,27dc2d34bda2109397c40b5cf8a869c55378a1b9
# Push it to GitHub
git push --set-upstream origin backport-56586-to-release-3_34
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-release-3_34

Then, create a pull request where the base branch is release-3_34 and the compare/head branch is backport-56586-to-release-3_34.

[agiudiceandrea]

Hi @3nids, does this PR also fix #53933 (which, based on the @nirvn comment #53933 (comment), was allegedly fixed by #54725, but actually not fixed yet #53933 (comment) #53321 (comment))?

[3nids]

yes I would say/think/hope that it's fixed....

[agiudiceandrea]

@3nids unfortunately it looks like the issue #53933 still occurs even using the Browser or the Data Source Manager of the latest QGIS 3.37.0-Master c997d5a8d9 with a new QGIS user profile:

Video_2024-03-20_172527_edit.mp4

[agiudiceandrea]

@3nids, it seems the issue #53321, which was allegedly fixed by this PR, still occurs: see #56713 (comment).

[sayers67]

Still an issue for WMS/WFS in 3.36.0-Maidenhead, Qt version 5.15.3, Python version, 3.9.18, GDAL/OGR version 3.8.4