Follow-up to my last post: you can turn off committing after conflict resolution in GoLand by clicking “Modify options” in the Merge dialog and selecting “Do not commit the merge result.” This should display the --no-commit flag.
Ok, I admit it’s pretty close to how it works on the command line; although not when you have conflicts, and the only time I merge in GoLand instead of the command line is when I need to resolve conflicts (I prefer the diff/merge tools there). But to be fair to GoLand, it doesn’t know about my merging preferences.