error functions now return a never type

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "remux"
-version = "0.3.2"
+version = "0.3.6"
 edition = "2021"
 authors = [ "Valerie Wolfe <sleeplessval@gmail.com>" ]
 description = "A friendly command shortener for tmux"

README.md

@@ -47,8 +47,7 @@ tmux swi -t foo
 rmux s foo
 
 #	cd to session path
-tmux run 'printf "#{session_path}" > /tmp/tmux_path'
-cd `cat /tmp/tmux_path`
+cd `tmux display-mes -p "#{session_path}"`
 cd `rmux p`
 
 ```
@@ -93,6 +92,19 @@ using an AUR package manager such as <a href="https://github.com/Morganamilo/par
 Install the package using Cargo with the command <code>cargo install tmux-remux</code>.
 </details>
 
+### Supplemental
+
+<details>
+<summary>Bash Completions</summary>
+Copy <code>bash-completion/remux</code> to the appropriate directory, typically
+<code>/usr/share/bash-completion</code>.
+</details>
+
+<details>
+<summary>Man Page: Section 1</summary>
+Copy <code>man/remux.1</code> into <code>/usr/share/man/man1/</code>.
+</details>
+
 ## Configuration
 
 The pretty-print attached symbol (default: `*`) can be set manually by setting `REMUX_ATTACH_SYMBOL`.

bash-completion/remux

@@ -0,0 +1,19 @@
+_remux() {
+	local word
+	COMPREPLY=()
+	word="${COMP_WORDS[COMP_CWORD]}"
+
+	case $COMP_CWORD in
+	1)
+		COMPREPLY=( `compgen -W 'attach detach has help list new path switch title' -- "$word"` )
+		;;
+	2)
+		COMPREPLY=( `compgen -W "$(remux l -q $word)"` )
+		;;
+	esac
+
+	return 0
+}
+
+complete -F _remux remux
+

man/remux.1

@@ -0,0 +1,177 @@
+.Dd $Mdocdate$
+.Dt REMUX 1
+.Os
+.Sh NAME
+.Nm remux
+.Nd a command shortener for
+.Xr tmux 1
+.Sh SYNOPSIS
+.Nm remux
+.Op Fl dhnqrtv
+.Op Ar command
+.Op args...
+.Sh DESCRIPTION
+.Nm
+is a wrapper and command shortener for
+.Xr tmux 1 ,
+primarily focused on improving the ergonomics of using named sessions.
+.Pp
+If no command is provided, remux will use the context action. Inside a repository, remux will attach or create. If in a session or outside a repository, remux will list sessions.
+.Sh COMMANDS
+.Nm remux
+commands are split into two categories: global commands, which can be used anywhere, and session commands, which can only be used from inside a session.
+.Ss GLOBAL COMMANDS
+.Bl -tag -width Ds
+.It Xo Ic attach
+.Op Fl dnr
+.Op Ar title
+.Op Ar window
+.Xc
+.Bd -literal -compact
+aliases: a
+Attaches to an existing session.
+.Ed
+.Pp
+.Bl -tag -width Ds -compact
+.It Fl d , Fl -detach
+Detach all other connections to the session.
+.It Fl n , Fl -nest
+Allow nesting (attaching a session from inside another session).
+.It Fl r , Fl -read-only
+Attach the session in read-only mode.
+.It Ar title
+The title of the target session. If not given, remux will try to use the name of the repository containing the current directory.
+.It Ar window
+The name of the window to attach to.
+.El
+.It Xo Ic detach
+.Op Ar title
+.Xc
+.Bd -literal -compact
+aliases: d
+Detaches all clients from the target session.
+.Ed
+.It Xo Ic has
+.Op Fl q
+.Op Ar title
+.Xc
+.Bd -literal -compact
+aliases: h
+Checks whether or not a session exists.
+.Ed
+.Pp
+.Bl -tag -width Ds -compact
+.It Fl q , Fl -quiet
+Run silently without printing to standard output.
+.It Ar title
+The title of the target session. If not given, remux will attempt to use the name of the repository containing the current directory.
+.El
+.It Ic list
+.Bd -literal -compact
+aliases: l, ls
+Pretty-prints a list of tmux sessions.
+.Ed
+.It Xo Ic new
+.Op Fl dn
+.Op Fl t\ |\ --target Ar path
+.Op Ar title
+.Op Ar command
+.Xc
+.Bd -literal -compact
+aliases: n
+Creates a new session.
+.Ed
+.Pp
+.Bl -tag -width Ds -compact
+.It Fl d , Fl -detach
+Creates the session without attaching.
+.It Fl n , Fl -nest
+Allow nesting (attaching a session from inside another session).
+.It Fl t , Fl -target Ar path
+Sets the session path to the provided directory.
+.It Ar title
+Create the session with the given title. If not given, remux will attempt to use the name of the repository containing the current directory.
+.El
+.El
+.Ss SESSION COMMANDS
+.Bl -tag -width Ds
+.It Ic path
+.Bd -literal -compact
+aliases: p
+Prints the session path.
+.Ed
+.It Xo Ic switch
+.Op Fl rd
+.Op Ar title
+.Xc
+.Bd -literal -compact
+aliases: s
+Switches from the current session to the target.
+.Ed
+.Pp
+.Bl -tag -width Ds -compact
+.It Fl d , Fl -detach
+Detaches other clients from the target session.
+.It Fl r , Fl -read-only
+Switch to the target session in read-only mode.
+.It Ar title
+The title of the session to switch to. If blank, the previous session will be used.
+.El
+.It Ic title
+.Bd -literal -compact
+aliases: t, which
+Prints the session title.
+.El
+.Sh ENVIRONMENT
+.Bl -tag -width Ds
+.It Ev REMUX_ATTACH_SYMBOL
+Changes the symbol displayed for attached sessions in the
+.Ic list
+command.
+Default: '*'
+.It Ev REMUX_CURRENT_SYMBOL
+Changes the symbol displayed for the current session in the
+.Ic list
+command.
+Default: '>'
+.It Ev REMUX_NEW_WINDOW
+Provides a default windows name when creating a new session. Unused if empty.
+Default: (unset)
+.It Ev REMUX_PREVIOUS_SYMBOL
+Changes the symbol displayed for the previous session in the
+.Ic list
+command.
+Default: '-'
+.It Ev REMUX_REPO_FILE
+The filename to match on when trying to find the root of a repository.
+Default: '.git'
+.El
+.Sh EXIT STATUS
+.Bl -tag -Width Ds
+.It 1
+Unmatched command name.
+.It 2
+Unmatched target session.
+.It 3
+Unmatched help topic.
+.It 4
+Missing or invalid target; target was not given or is the same as the current session.
+.It 5
+.Nm remux
+is not running from within a terminal.
+.It 6
+Nesting error; nest flag is missing or inappropriate.
+.It 7
+A session command was attempted outside a session.
+.Sh EXAMPLES
+Use
+.Ic path
+to navigate to the session path:
+.Pp
+.Dl $ cd `remux p`
+.Pp
+.Sh SEE ALSO
+.Xr tmux 1
+.Sh AUTHORS
+.An -nosplit
+.An Valerie Wolfe Aq Mt sleeplessval@gmail.com

src/command/session.rs

@@ -1,52 +1,67 @@
 //!	commands accessible from within a session
-use std::fs::read_to_string;
 
-use pico_args::Arguments;
 use tmux_interface::{
 	Tmux,
 	commands
 };
 
-use crate::{ error, flag, util };
+use crate::{
+	error,
+	state::State,
+	util::{
+		self,
+		message,
+		MSG_PREVIOUS, MSG_SESSION_PATH, NULL
+	}
+};
 
-const TMP_ROOT: &str = "/tmp/remux_path";
+pub fn path(state: &mut State) {
+	state.session_enforce("path");
 
-pub fn switch(pargs: &mut Arguments) {
+	if let Some(message) = message(MSG_SESSION_PATH) {
+		println!("{message}");
+	}
+}
+
+pub fn switch(state: &mut State) {
 	util::terminal_enforce();
 	//	refuse to run outside a session
-	util::session_enforce("switch");
+	state.session_enforce("switch");
 
 	//	consume optional flags
-	let read_only = pargs.contains(flag::READ_ONLY);
-	//TODO: -d flag handling needs to be done manually
+	let read_only = state.flags.read_only;
+	let detach_other = state.flags.detached;
 
-	let args = pargs.clone().finish();
-	if args.len() < 1 { error::missing_target(); }
-	let target = args.get(0).unwrap().to_string_lossy().to_string();
+	let args = state.args.clone().finish();
+	let target: String = match if let Some(inner) = args.get(0) { inner.to_str() } else { None } {
+		None		|
+		Some("-")	=>	if let Some(prev) = message(MSG_PREVIOUS) { prev }
+						else { error::missing_target() },
+
+		Some(inner)	=>	inner.to_owned()
+	};
 
 	let exists = util::session_exists(target.clone());
 	if !exists { error::no_target(target.clone()); }
 
+	let mut tmux = Tmux::new();
+
+	if detach_other {
+		let detach = commands::DetachClient::new()
+			.target_session(&target);
+		tmux = tmux.add_command(detach);
+	}
+
 	let mut switch = commands::SwitchClient::new();
-	switch = switch.target_session(target);
+	switch = switch.target_session(&target);
 	if read_only { switch.read_only = true; }
 
-	Tmux::new()
-		.add_command(switch)
-		.output().ok();
+	tmux.add_command(switch)
+		.stderr(NULL).output().ok();
 }
 
-pub fn path() {
-	util::session_enforce("path");
-
-	let exec = commands::Run::new().shell_command("printf '#{session_path}' > ".to_string() + TMP_ROOT);
-	Tmux::new()
-		.add_command(exec)
-		.output().ok();
-
-	if let Ok(text) = read_to_string(TMP_ROOT) {
-		println!("{text}");
-		std::fs::remove_file(TMP_ROOT).ok();
-	}
+pub fn title(state: State) {
+	state.session_enforce("title");
+	if let Some(title) = state.title { println!("{title}"); }
 }
 

src/command/share.rs

@@ -1,8 +1,5 @@
 //! globally available tmux commands.
-use std::{
-	ffi::OsString,
-	process::exit
-};
+use std::process::exit;
 
 use pico_args::{ Arguments, Error };
 use termion::{ color, style };
@@ -12,34 +9,35 @@ use tmux_interface::{
 };
 
 use crate::{
-	env::{ self, env_var },
+	env::{
+		self,
+		env_var,
+		SYMBOL_ATTACH, SYMBOL_CURRENT, SYMBOL_PREV
+	},
 	error,
 	flag,
-	util
+	state::State,
+	util::{
+		self,
+		message,
+		MSG_PREVIOUS, NULL
+	}
 };
 
-pub fn attach(pargs: &mut Arguments) {
-	//	must be run from terminal
+pub fn attach(state: &mut State) {
 	util::terminal_enforce();
-	//	don't allow unflagged nests
-	util::prevent_nest();
+	state.nest_init();
 
 	//	consume optional flags
-	let read_only = pargs.contains(flag::READ_ONLY);
-	let detach_other = pargs.contains(flag::DETACH);
+	let read_only = state.flags.read_only;
+	let detach_other = state.flags.detached;
 
-	let args = pargs.clone().finish();
-	let target: String;
-	let window: Option<&OsString>;
-	if args.len() < 1 {
-		//	missing name will attempt to fall back to repository
-		target = util::repo_fallback();
-		if !util::session_exists(target.clone()) { error::missing_target(); }
-		window = None;
-	} else {
-		target = args.get(0).unwrap().to_string_lossy().to_string();
-		window = args.get(1);
-	}
+	//	consume arguments
+	let target = state.target_title().unwrap();
+	let window = state.target();
+
+	//	do not allow attaching to the same session
+	if state.session && target == state.title.clone().unwrap() { error::same_session(); }
 
 	//	make sure the session exists
 	let exists = util::session_exists(target.clone());
@@ -54,43 +52,41 @@ pub fn attach(pargs: &mut Arguments) {
 	let select_window: Option<commands::SelectWindow>;
 	if let Some(window) = window {
 		let mut command = commands::SelectWindow::new();
-		command.target_window = Some(window.to_string_lossy());
+		command.target_window = Some(window.into());
 		select_window = Some(command);
 	} else { select_window = None; }
 
 	//	build dispatch
 	let mut tmux = Tmux::new().add_command(attach);
 	if let Some(select_window) = select_window { tmux = tmux.add_command(select_window); }
-	tmux.output().ok();
+	tmux.stderr(NULL).output().ok();
+
+	state.nest_deinit();
 }
 
-pub fn context_action() {
-	let repo = util::repo_root(std::env::current_dir().unwrap());
-	if !env::tmux() && repo.is_some() {
-		let target = util::repo_fallback();
-		let mut args = Arguments::from_vec( vec![(&target).into()] );
-		if util::session_exists(&target) {
-			attach(&mut args);
-		} else {
-			new(&mut args);
+pub fn context_action(state: &mut State) {
+	if !state.session {
+		if let Some(repository) = &state.repository {
+			let target = repository.name.clone();
+			let mut args = Arguments::from_vec( vec![(&target).into()] );
+			let mut substate = State::new(&mut args);
+			substate.flags = state.flags.clone();
+			if util::session_exists(&target) {
+				attach(&mut substate);
+			} else {
+				new(&mut substate);
+			}
+			return;
 		}
-		return;
-	} else {
-		//	fallback behavior is list
-		list();
 	}
+	//	fallback behavior is list
+	list(state);
 }
 
-pub fn detach(pargs: &mut Arguments) {
+pub fn detach(state: &mut State) {
 	util::terminal_enforce();
-	//	get target or fallback
-	let args = pargs.clone().finish();
-	let target: String;
-	if args.len() < 1 {
-		target = util::repo_fallback();
-	} else {
-		target = args.get(0).unwrap().to_string_lossy().to_string();
-	}
+
+	let target = state.target_title().unwrap();
 
 	//	make sure the session exists
 	let exists = util::session_exists(target.clone());
@@ -104,18 +100,12 @@ pub fn detach(pargs: &mut Arguments) {
 		.disable_echo().output().ok();
 }
 
-pub fn has(pargs: &mut Arguments) {
+pub fn has(state: &mut State) {
 	//	consume optional flags
-	let quiet = pargs.contains(flag::QUIET);
+	let quiet = state.flags.quiet;
 
-	//	get target or fallback
-	let args = pargs.clone().finish();
-	let target: String;
-	if args.len() < 1 {
-		target = util::repo_fallback();
-	} else {
-		target = args.get(0).unwrap().to_string_lossy().to_string();
-	}
+	//	get target
+	let target = state.target_title().unwrap();
 
 	//	run command
 	let success = util::session_exists(target.clone());
@@ -132,10 +122,13 @@ pub fn has(pargs: &mut Arguments) {
 	exit( if success { 0 } else { 1 });
 }
 
-pub fn list() {
+pub fn list(state: &mut State) {
 	//	get session list
 	let sessions = util::get_sessions().unwrap_or(Vec::new());
 
+	let search = state.target();
+	let previous = message(MSG_PREVIOUS);
+
 	//	handle empty case
 	if sessions.len() == 0 {
 		println!("no sessions");
@@ -143,56 +136,69 @@ pub fn list() {
 	}
 
 	//	get attached session symbol
-	let attach_symbol = env_var(env::ATTACH_SYMBOL);
+	let attach_symbol	= env_var(SYMBOL_ATTACH);
+	let current_symbol	= env_var(SYMBOL_CURRENT);
+	let prev_symbol		= env_var(SYMBOL_PREV);
 
 	//	pretty print session list
-	println!("sessions:");
-	for session in sessions.into_iter() {
-		let group = session.group.unwrap_or("[untitled]".to_string());
-		let id = session.id.unwrap();
-		let attached = session.attached.unwrap_or(0) > 0;
+	if !state.flags.quiet { println!("sessions:"); }
+	for session in sessions {
+		let name = session.name.unwrap_or("[untitled]".to_string());
 
-		println!(
-			"   {group} ({bold}{blue}{id}{reset}) {bold}{green}{attach}{reset}",
-			//	values
-			attach		= if attached { attach_symbol.clone() } else { "".to_string() },
-			//	formatting
-			bold		= style::Bold,
-			blue		= color::Fg(color::Blue),
-			green		= color::Fg(color::LightGreen),
-			reset		= style::Reset
-		);
+		if search.is_some() && !name.starts_with(search.as_ref().unwrap()) { continue; }
+
+		if !state.flags.quiet {
+			let id = session.id.unwrap();
+
+			let attached = session.attached.unwrap_or(0) > 0;
+
+			let compare = Some(name.clone());
+			let marker =
+				if compare == state.title { current_symbol.clone() }
+				else if state.session && compare == previous { prev_symbol.clone() }
+				else { " ".to_string() };
+
+			println!(
+				" {marker} {name}{reset} ({bold}{blue}{id}{reset}) {bold}{green}{attach}{reset}",
+				//	values
+				attach		= if attached { attach_symbol.clone() } else { "".to_string() },
+				//	formatting
+				bold		= style::Bold,
+				blue		= color::Fg(color::Blue),
+				green		= color::Fg(color::LightGreen),
+				reset		= style::Reset,
+			);
+		} else {
+			print!("{name} ");
+		}
 	}
 }
 
-pub fn new(pargs: &mut Arguments) {
+pub fn new(state: &mut State) {
 	util::terminal_enforce();
-	//	don't allow unflagged nesting
-	util::prevent_nest();
 
 	//	get optional flags
-	let detached = pargs.contains(flag::DETACH);
-	let target_dir: Result<String, Error> = pargs.value_from_str(flag::TARGET);
+	let detached = state.flags.detached;
+	let target_dir: Result<String, Error> = state.args.value_from_str(flag::TARGET);
+
+	//	delayed nest_init; detached behavior conflicts with nest
+	if !detached { state.nest_init(); }
+	else if state.flags.nested { error::conflict_nest(Some("detached session is not nesting")); }
 
 	//	get environment variables
 	let window_name = env_var(env::NEW_WINDOW_NAME);
 
-	//	get target or fallback
-	let args = pargs.clone().finish();
-	let title: String;
-	let command: Option<&OsString>;
-	if args.len() < 1 {
-		//	attempt repo fallback
-		title = util::repo_fallback();
-		command = None;
-	} else {
-		title = args.get(0).unwrap().to_string_lossy().to_string();
-		command = args.get(1);
-	}
+	//	consume arguments
+	let title = state.target_title().unwrap();
+	let command = state.target();
+
+	//	don't allow duplicate names
+	let exists = util::session_exists(title.clone());
+	if exists { error::target_exists(title.clone()); }
 
 	let mut new = commands::NewSession::new();
-	new = new.group_name(title);
-	if let Some(command) = command { new.shell_command = Some(command.to_string_lossy()); }
+	new = new.session_name(title);
+	if let Some(command) = command { new.shell_command = Some(command.into()); }
 	if detached { new.detached = true; }
 	if let Ok(target_dir) = target_dir { new = new.start_directory(target_dir); }
 
@@ -205,6 +211,6 @@ pub fn new(pargs: &mut Arguments) {
 		tmux = tmux.add_command(auto_name);
 	}
 
-	tmux.output().ok();
+	tmux.stderr(NULL).output().ok();
 }
 

src/env.rs

@@ -2,12 +2,16 @@ use std::env::var;
 
 pub type EnvVar = (&'static str, &'static str);
 
-pub static ATTACH_SYMBOL: EnvVar	= ("REMUX_ATTACH_SYMBOL", "*");
-pub static NEW_WINDOW_NAME: EnvVar	= ("REMUX_NEW_WINDOW", "");
+pub const NEW_WINDOW_NAME:	EnvVar	= ("REMUX_NEW_WINDOW", "");
+pub const REPO_FILE:		EnvVar	= ("REMUX_REPO_FILE", ".git");
+pub const SYMBOL_ATTACH:	EnvVar	= ("REMUX_ATTACH_SYMBOL", "*");
+pub const SYMBOL_CURRENT:	EnvVar	= ("REMUX_CURRENT_SYMBOL", ">");
+pub const SYMBOL_PREV:		EnvVar	= ("REMUX_PREVIOUS_SYMBOL", "-");
 
+pub const TMUX: &str				= "TMUX";
+
+///	get or default an environment variable
 pub fn env_var(envvar: EnvVar) -> String {
 	var(envvar.0).unwrap_or(envvar.1.to_string())
 }
 
-pub fn tmux() -> bool { !var("TMUX").unwrap_or("".to_string()).is_empty() }
-

src/error.rs

@@ -1,45 +1,77 @@
 use std::process::exit;
 
 ///	no subcommand that matches user input; code 1
-pub fn no_subcommand(subcommand: String) {
-	println!("remux: no command match for \"{subcommand}\"");
+pub fn no_subcommand(subcommand: String) -> ! {
+	eprintln!("remux: no command match for \"{subcommand}\"");
 	exit(1);
 }
 
+
 ///	target session not found; code 2
-pub fn no_target<S: Into<String>>(target: S) {
+pub fn no_target<S: Into<String>>(target: S) -> ! {
 	let target = target.into();
-	println!("remux: no session \"{target}\" exists");
+	eprintln!("remux: no session \"{target}\" exists");
 	exit(2);
 }
 
+
 ///	help topic doesn't exist; code 3
-pub fn no_help(topic: String) {
-	println!("remux: no help for \"{topic}\"");
+pub fn no_help(topic: String) -> ! {
+	eprintln!("remux: no help for \"{topic}\"");
 	exit(3);
 }
 
+
 ///	user provided no target; code 4
-pub fn missing_target() {
-	println!("remux: no target provided");
+pub fn missing_target() -> ! {
+	eprintln!("remux: no target provided");
 	exit(4);
 }
 
+///	refuse to attach to current session; code 4
+pub fn same_session() -> ! {
+	eprintln!("remux: cannot attach to same session");
+	exit(4);
+}
+
+///	a session with the target name already exists; code 4
+pub fn target_exists<S: Into<String>>(target: S) -> ! {
+	let target = target.into();
+	eprintln!("remux: session \"{target}\" already exists");
+	exit(4);
+}
+
+
 ///	non-terminal environment prevention; code 5
-pub fn not_terminal() {
-	println!("remux: not running from a terminal");
+pub fn not_terminal() -> ! {
+	eprintln!("remux: not running from a terminal");
 	exit(5);
 }
 
+
 ///	tried to nest while not in a session; code 6
-pub fn not_nesting() {
-	println!("remux: cannot use nesting flag outside a TMUX session");
+pub fn not_nesting() -> ! {
+	eprintln!("remux: inappropriate nesting flag (-n); not in a session");
 	exit(6);
 }
 
+///	operation requires nesting flag; code 6
+pub fn prevent_nest() -> ! {
+	eprintln!("remux: the nesting flag (-n) is required for nesting operation");
+	exit(6);
+}
+
+///	operation conflicts with nesting flag; code 6
+pub fn conflict_nest(reason: Option<&'static str>) -> ! {
+	if let Some(reason) = reason { eprintln!("remux: inappropriate nesting flag (-n): {reason}"); }
+	else { eprintln!("remux: nesting flag (-n) is inappropriate for this operation."); }
+	exit(6);
+}
+
+
 ///	tried to run a session command outside a session; code 7
-pub fn not_in_session(cmd: &'static str) {
-	println!("remux: '{cmd}' must be run from within a session");
+pub fn not_in_session(cmd: &'static str) -> ! {
+	eprintln!("remux: '{cmd}' must be run from within a session");
 	exit(7);
 }
 

src/flag.rs

@@ -1,4 +1,6 @@
 
+use pico_args::Arguments;
+
 type Flag = [&'static str;2];
 
 pub static DETACH: Flag		= ["-d", "--detach"];
@@ -9,3 +11,41 @@ pub static READ_ONLY: Flag	= ["-r", "--read-only"];
 pub static TARGET: Flag		= ["-t", "--target"];
 pub static VERSION: Flag	= ["-v", "--version"];
 
+pub struct Flags {
+	pub detached: bool,
+	pub nested: bool,
+	pub quiet: bool,
+	pub read_only: bool,
+	pub target: Option<String>,
+}
+
+impl Flags {
+
+	pub fn from(args: &mut Arguments) -> Flags {
+		let detached	= args.contains(DETACH);
+		let nested		= args.contains(NEST);
+		let quiet		= args.contains(QUIET);
+		let read_only	= args.contains(READ_ONLY);
+		let target		= args.value_from_str(TARGET).ok();
+
+		Flags {
+			detached,
+			nested,
+			quiet,
+			read_only,
+			target
+		}
+	}
+
+	pub fn clone(&self) -> Flags {
+		Flags {
+			detached: self.detached,
+			nested: self.nested,
+			quiet: self.quiet,
+			read_only: self.read_only,
+			target: None
+		}
+	}
+
+}
+

src/help.rs

@@ -25,6 +25,7 @@ commands:
 
    path       print session path (session)
    switch     switch to another session (session)
+   title      print session title (session)
 
 Use 'remux help <command>' to see detailed help text for each command.
 
@@ -101,7 +102,7 @@ flags:
    -n, --nest             Create the session inside another session.
    -t, --target <dir>     Sets the target directory for the new session."),
 
-		Some("root")
+		Some("p" | "path")
 		=>
 println!("remux path
 Print the session path (#{{session_path}}) to standard output.
@@ -126,6 +127,16 @@ flags:
    -r, --read-only        Attach the target session as read-only."),
 
 
+		Some("w" | "which" | "title")
+			=>
+println!("remux which
+Print the title of the current session.
+
+usage: remux which
+       remux w
+       remux title"),
+
+
 //	TOPIC HELP
 
 		Some("env" | "vars")
@@ -137,10 +148,15 @@ REMUX_ATTACH_SYMBOL
    by the 'list' command.
    Default: '*'
 
+REMUX_CURRENT_SYMBOL
+   Changes the symbol displayed to denote the current session
+   in the 'list' command.
+   Default: '>'
+
 REMUX_NEW_WINDOW
    Provides a default window name when creating a session with
    the 'new' command, if not empty.
-   Default: ''"),
+   Default: (unset)"),
 
 		//	not found
 		_	=>	error::no_help(topic.unwrap())

src/main.rs

@@ -1,4 +1,3 @@
-use std::env::{ set_var, var };
 
 use pico_args::Arguments;
 
@@ -7,9 +6,11 @@ mod env;
 mod error;
 mod flag;
 mod help;
+mod state;
 mod util;
 
 use help::{ help, version };
+use state::State;
 
 static VERSION: &str = env!("CARGO_PKG_VERSION");
 
@@ -28,52 +29,44 @@ fn main() {
 		return;
 	}
 
-	let nesting = args.contains(flag::NEST);
-	let tmux_var = var("TMUX").ok();
-	if nesting {
-		if tmux_var.is_none() {
-			error::not_nesting();
-		}
-		set_var("TMUX", "");
-	}
+	let mut state = State::new(&mut args);
 
-	let subcommand = args.subcommand().unwrap();
+	let target = state.target();
 
 	//	invoke subcommand function
-	match subcommand.as_deref() {
+	match target.as_deref() {
 		Some("help")
 			=>	help(&mut args),
 		None
-			=>	command::share::context_action(),
+			=>	command::share::context_action(&mut state),
 
 		Some("a" | "attach")
-			=>	command::share::attach(&mut args),
+			=>	command::share::attach(&mut state),
 
 		Some("d" | "detach")
-			=>	command::share::detach(&mut args),
+			=>	command::share::detach(&mut state),
 
 		Some("h" | "has")
-			=>	command::share::has(&mut args),
+			=>	command::share::has(&mut state),
 
 		Some("l" | "ls" | "list")
-			=>	command::share::list(),
+			=>	command::share::list(&mut state),
 
 		Some("n" | "new")
-			=>	command::share::new(&mut args),
+			=>	command::share::new(&mut state),
 
 		Some("p" | "path")
-			=>	command::session::path(),
+			=>	command::session::path(&mut state),
 
 		Some("s" | "switch")
-			=>	command::session::switch(&mut args),
+			=>	command::session::switch(&mut state),
+
+		Some("t" | "title" | "which")
+			=>	command::session::title(state),
 
 		_
-			=>	error::no_subcommand(subcommand.unwrap())
+			=>	error::no_subcommand(target.unwrap())
 	}
 
-	//	re-set TMUX var if we unset it for nest mode
-	if nesting {
-		set_var("TMUX", tmux_var.unwrap());
-	}
 }
 

src/state.rs

@@ -0,0 +1,93 @@
+use std::{
+	env,
+	path::PathBuf
+};
+
+use pico_args::Arguments;
+
+use crate::{
+	env::{ env_var, REPO_FILE, TMUX },
+	error,
+	flag::Flags,
+	util::{ find, message, MSG_SESSION_NAME }
+};
+
+pub struct State<'a> {
+	pub args: &'a mut Arguments,
+	pub flags: Flags,
+
+	pub session: bool,
+	tmux_var: Option<String>,
+	pub title: Option<String>,
+
+	pub repository: Option<Repository>
+}
+
+impl State<'_> {
+
+	pub fn new(args: &mut Arguments) -> State {
+		let flags = Flags::from(args);
+		let tmux_var = env::var(TMUX).ok();
+		let session = tmux_var.is_some();
+		let title = if session { message(MSG_SESSION_NAME) } else { None };
+		let repository = Repository::find();
+
+		State {
+			args,
+			flags,
+
+			session,
+			tmux_var,
+			title,
+
+			repository
+		}
+	}
+
+	pub fn nest_init(&self) {
+		if self.flags.nested {
+			if self.session { env::set_var(TMUX, ""); }		//	nesting & session	=> ok
+			else { error::not_nesting(); }					//	nesting & !session	=> error
+		} else if self.session { error::prevent_nest(); }	//	!nesting & session	=> error
+															//	!nesting & !session	=> ok
+	}
+
+	pub fn nest_deinit(&self) {
+		if self.flags.nested && self.session {
+			env::set_var(TMUX, self.tmux_var.as_ref().unwrap());
+		}
+	}
+
+	pub fn session_enforce(&self, cmd: &'static str) {
+		if !self.session { error::not_in_session(cmd); }
+	}
+
+	pub fn target(&mut self) -> Option<String> { self.args.subcommand().unwrap_or(None) }
+	pub fn target_title(&mut self) -> Option<String> {
+		let from_args = self.target();
+		if from_args.is_some() { return from_args; }
+		else if let Some(repository) = &self.repository { Some(repository.name.clone()) }
+		else { error::missing_target() }
+	}
+}
+
+
+pub struct Repository {
+	pub path: PathBuf,
+	pub name: String
+}
+
+impl Repository {
+	pub fn find() -> Option<Repository> {
+		let path = find(&env_var(REPO_FILE), env::current_dir().unwrap());
+		if let Some(path) = path {
+			let name = path.file_name().unwrap().to_string_lossy().to_string();
+			let inner = Repository {
+				path,
+				name
+			};
+			Some(inner)
+		} else { None }
+	}
+}
+

src/util.rs

@@ -1,21 +1,36 @@
 use std::{
-	env::current_dir,
 	io::{ stdout, IsTerminal },
-	path::PathBuf,
-	process::exit
+	path::PathBuf
 };
 
 use tmux_interface::{
-	Session, Tmux,
+	Session, StdIO, Tmux,
 
 	commands,
 	variables::session::SessionsCtl
 };
 
-use crate::{
-	env,
-	error
-};
+use crate::error;
+
+pub const NULL: Option<StdIO> = Some(StdIO::Null);
+
+pub const MSG_PREVIOUS:		&str	= "#{client_last_session}";
+pub const MSG_SESSION_NAME:	&str	= "#S";
+pub const MSG_SESSION_PATH:	&str	= "#{session_path}";
+pub const MSG_WINDOW_NAME:	&str	= "#{window_name}";
+
+pub fn message(fstr: &str) -> Option<String> {
+	let message = commands::DisplayMessage::new().print().message(fstr);
+
+	let result = Tmux::new().add_command(message).output();
+	if let Ok(output) = result {
+		let text = String::from_utf8(output.0.stdout);
+		if let Ok(title) = text {
+			if title.len() > 0 { Some(title[0..title.len() - 1].to_owned()) }
+			else { None }
+		} else { None }
+	} else { None }
+}
 
 ///	return a Vec of all sessions or None
 pub fn get_sessions() -> Option<Vec<Session>> {
@@ -25,24 +40,12 @@ pub fn get_sessions() -> Option<Vec<Session>> {
 	} else { return None; }
 }
 
-///	show the tmux nest text if env var is not unset
-pub fn prevent_nest() {
-	if env::tmux() {
-		println!("To nest sessions, use the -n flag.");
-		exit(6);
-	}
-}
-
-///	enforce a command is being used in-session
-pub fn session_enforce(cmd: &'static str) {
-	if !env::tmux() { error::not_in_session(cmd); }
-}
-
 ///	check whether a target session exists
 pub fn session_exists<S: Into<String>>(target: S) -> bool {
 	let has_session = commands::HasSession::new()
 		.target_session(target.into());
 	Tmux::new().add_command(has_session)
+		.stderr(NULL)
 		.status()
 		.unwrap()
 		.success()
@@ -53,23 +56,12 @@ pub fn terminal_enforce() {
 	if !stdout().is_terminal() { error::not_terminal(); }
 }
 
-///	attempt to return the repo name or exit
-pub fn repo_fallback() -> String {
-	let repo = repo_root(current_dir().unwrap());
-	if repo.is_none() { error::missing_target(); }
+///	recursively propagate up directories to find a child
+pub fn find(target: &str, path: PathBuf) -> Option<PathBuf> {
+	if path.join(target).exists() { return Some(path); }
 
-	let target = repo.unwrap().file_name().unwrap().to_string_lossy().to_string();
-	target
-}
-
-///	recursively attempt to find a git root directory
-pub fn repo_root(path: PathBuf) -> Option<PathBuf> {
-	//	if .git dir is found, return
-	if path.join(".git").exists() { return Some(path); }
-
-	//	otherwise, attempt to traverse
 	let parent = path.parent();
-	if let Some(parent) = parent { repo_root(parent.to_path_buf()) }
+	if let Some(parent) = parent { return find(target, parent.to_path_buf()) }
 	else { None }
 }