Module worktree_convert_compare 

The read-only comparison of the old tree of a conversion with the installed one. What: A read-only comparison of the old tree of a conversion with the installed one: the first entry of the old tree that the installed tree does not hold in the same form, or that this command does not delete. Why: The old tree is deleted only after the installed copy is known to hold everything in it. The comparison changes neither tree and copies nothing: a difference keeps the old tree and says which entry differs, and whoever knows which version is wanted settles it. An entry on another device (a nested subvolume or a mount point) is reported the same way, because deleting it is not this command’s to do.

In TS you’d write (pseudocode):

const difference = await firstDifference(oldRoot, installedRoot); // undefined when the installed tree holds all of it

Functions

first_difference

What: The first way the old tree at old is not held by the installed tree at installed, or nothing when it is held whole. Why: See the module description. A file is the same when its type, size and modification time are, a link when its target is; the installed tree may hold more than the old one, because it has been in use since the exchange.