Tmux has an option to have the #{pane_current_path} as a name for the current pane in the status line. This is great but has two short falls for me:
$HOME is not displayed as ~./. So, for example /home/ook/thingy/src would only be displayed as either src or ~/t/src.Is there a Tmux command that does this?
Bonus points if it works with powerline as well.
I'm using something similar to what you want:
setw -g window-status-format "#[underscore]#{?#{==:#{window_panes},1},,+}#[bold]#W#[nobold]:#{=|-24|…;s|$HOME|~|:pane_current_path}"
Stripping that down a bit to focus on the pane_current_path mangling:
"#{=|-24|…;s|$HOME|~|:pane_current_path}"
That replaces the home dir with ~ and removes all but the right-most 24 chars. Done this way, though, I note that the leading ~ is removed for long paths.
For just the leaf of the path:
"#{s|$HOME|~|;s|.*/||:pane_current_path}"
That time I put the ~ replacement first, so that when you're at home it displays ~ rather than <username>.
So to get closer to your ~/t/src example:
"#{s|$HOME|~|;s|/.*/|/…/|:pane_current_path}"
will render as ~/…/src. You should be able to use a modified pattern and a a backref, maybe combined with the #{= truncator, to get closer, but I'm not sure about getting all that right.
I tried to find something similar recently, in my case, for setting the window information (for the Tmux command choose-window) to something more informative than the default.
In the man page, the relevant information seems to be in the FORMATS section, which is also used by the status-{left,right} commands:
FORMATS
Certain commands accept the -F flag with a format argument. This is a string which controls the output format of the command. Replacement variables are enclosed in ‘#{’ and ‘}’, for example ‘#{session_name}’. The possible variables are listed in the table below, or the name of a tmux option may be used for an option's value. Some variables have a shorter alias such as ‘#S’, and ‘##’ is replaced by a single ‘#’.
Conditionals are available by prefixing with ‘?’ and separating two alternatives with a comma; if the specified variable exists and is not zero, the first alternative is chosen, otherwise the second is used. For example ‘#{?session_attached,attached,not attached}’ will include the string ‘attached’ if the session is attached and the string ‘not attached’ if it is unattached, or ‘#{?automatic-rename,yes,no}’ will include ‘yes’ if automatic-rename is enabled, or ‘no’ if not.
A limit may be placed on the length of the resultant string by prefixing it by an ‘=’, a number and a colon. Positive numbers count from the start of the string and negative from the end, so ‘#{=5:pane_title}’ will include at most the first 5 characters of the pane title, or ‘#{=-5:pane_title}’ the last 5 characters. Prefixing a time variable with ‘t:’ will convert it to a string, so if ‘#{window_activity}’ gives ‘1445765102’, ‘#{t:window_activity}’ gives ‘Sun Oct 25 09:25:02 2015’. The ‘b:’ and ‘d:’ prefixes are basename(3) and dirname(3) of the variable respectively. A prefix of the form ‘s/foo/bar/:’ will substitute ‘foo’ with ‘bar’ throughout.
In addition, the first line of a shell command's output may be inserted using ‘#()’. For example, ‘#(uptime)’ will insert the system's uptime. When constructing formats, tmux does not wait for ‘#()’ commands to finish; instead, the previous result from running the same command is used, or a placeholder if the command has not been run before. Commands are executed with the tmux global environment set (see the ENVIRONMENT section).
After some attempts, I can't seem to make the built-in sed-like method work with the #{pane_current_path} directory name. Since you can also use any shell command or environmental variables, though, you can simply use some variation of
set status-left "#(basename ${PWD})"
I don't know about Powerline compatibility, since at the moment I'm not using it.
