"Workspace" in location mode

[xiaq]

I actually do not know how common this is, but I often need to work with multiple "workspace" directories that have almost identical layouts. In fact they are just clones of the same repo.

The location mode is less useful when I need to constantly switch between workspaces. Assume that I am a Linux kernel guru who keeps multiple clones of kernel in /usr/src/linux. I have been in /usr/src/linux/repo1/foo/bar/quux and it is easy for me to go there; but I still cannot go to /usr/src/linux/repo2/foo/bar/quux quickly.

There is a quite simple (at least API-wise) solution to the problem. Allow users to define multiple workspace patterns, each associated with a workspace type. The configuration can look like edit:location:workspace-patterns = [&linux-ws='/usr/src/linux/[^/]+' &freebsd-ws='/usr/src/freebsd/[^/]+']

The pattern affect the behavior of the location mode in two ways:

• When recording directory history: if the directory is in a workspace, then in additional to the full path of the directory, also record a version by substituting the workspace part with the type of the workspace. For instance, if I go to /usr/src/linux/repo1/foo/bar/quux, two entries are written to the directory history: the full absolute path, and linux-ws/foo/bar/quux.

• When starting location mode: if the current directory is in a workspace, then find out its type, and show entries with the same workspace type. For instance, if I am in /usr/src/linux/repo100/lorem, then all linux-ws/ entries are shown. Entries for other workspaces are not shown.