ztmux 3.7.17

A Rust port of tmux — the full terminal multiplexer, server and client
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145

//! `ztmux clearall` — free the scrollback buffer of every pane at once.
//!
//! The write-side companion to [`super::history`]: where `history` shows which
//! panes are hoarding scrollback, `clear` runs `clear-history` on every pane
//! that holds any (optionally within one session with `-s`), reclaiming that
//! memory in a single command. Panes with an empty buffer are skipped. Like
//! `prune`, it is **dry-run by default** — it prints the panes it would clear and
//! how many lines each is holding — and only acts when `-f` / `--force` is given.

use super::tmux_query::{Pane, Snapshot, poll, ztmux_cmd};

/// Parsed invocation: optional session filter and the force flag.
struct Args {
    session: Option<String>,
    force: bool,
}

pub(crate) fn run(socket: &str) -> i32 {
    let args = parse_args();
    let snap = poll(socket);
    if let Some(e) = &snap.error {
        eprintln!("ztmux clear: {e}");
        return 1;
    }
    let targets = select(&snap, args.session.as_deref());
    if targets.is_empty() {
        eprintln!("ztmux clear: no panes with scrollback");
        return 1;
    }
    let total: i64 = targets.iter().map(|(_, _, n)| n).sum();
    if !args.force {
        println!(
            "would clear {} line(s) of scrollback across {} pane(s):",
            total,
            targets.len()
        );
        for (id, loc, lines) in &targets {
            println!("  {id} {loc} ({lines} lines)");
        }
        println!("(dry-run; pass -f to clear)");
        return 0;
    }
    let mut done = 0;
    for (id, _, _) in &targets {
        if ztmux_cmd(socket, &["clear-history", "-t", id])
            .status()
            .is_ok_and(|s| s.success())
        {
            done += 1;
        }
    }
    println!("cleared {done}/{} pane(s)", targets.len());
    i32::from(done != targets.len())
}

fn parse_args() -> Args {
    let argv: Vec<String> = std::env::args().collect();
    let rest = argv
        .iter()
        .position(|a| a == "clear")
        .map_or(&[][..], |i| &argv[i + 1..]);
    Args {
        session: rest.windows(2).find(|w| w[0] == "-s").map(|w| w[1].clone()),
        force: rest.iter().any(|a| a == "-f" || a == "--force"),
    }
}

/// Live panes holding scrollback (optionally within one session), as
/// `(id, location, lines)`, ordered by location. Panes with an empty buffer are
/// skipped — clearing them is a no-op.
fn select(snap: &Snapshot, session: Option<&str>) -> Vec<(String, String, i64)> {
    let mut sel: Vec<&Pane> = snap
        .panes
        .iter()
        .filter(|p| !p.dead && p.history_size > 0)
        .filter(|p| session.is_none_or(|s| p.session == s))
        .collect();
    sel.sort_by_key(|p| loc(p));
    sel.into_iter()
        .map(|p| (p.id.clone(), loc(p), p.history_size))
        .collect()
}

fn loc(p: &Pane) -> String {
    format!("{}:{}.{}", p.session, p.window, p.index)
}

#[cfg(test)]
mod tests {
    use super::*;

    fn pane(id: &str, sess: &str, win: i64, idx: i64, hist: i64) -> Pane {
        Pane {
            session: sess.into(),
            window: win,
            index: idx,
            id: id.into(),
            command: "zsh".into(),
            history_size: hist,
            ..Default::default()
        }
    }

    fn snap() -> Snapshot {
        Snapshot {
            panes: vec![
                pane("%0", "work", 0, 0, 0),   // empty buffer → skipped
                pane("%1", "work", 1, 0, 500), // has scrollback → included
                pane("%2", "ops", 0, 0, 9000), // has scrollback → included
            ],
            ..Default::default()
        }
    }

    #[test]
    fn only_panes_with_scrollback_are_selected() {
        let sel = select(&snap(), None);
        let ids: Vec<&str> = sel.iter().map(|(id, _, _)| id.as_str()).collect();
        // %2 (ops) sorts before %1 (work) by location; empty %0 excluded.
        assert_eq!(ids, vec!["%2", "%1"]);
    }

    #[test]
    fn session_filter_restricts_targets() {
        let sel = select(&snap(), Some("ops"));
        assert_eq!(sel.len(), 1);
        assert_eq!(sel[0].0, "%2");
        assert_eq!(sel[0].2, 9000);
    }

    #[test]
    fn no_scrollback_anywhere_yields_empty() {
        let s = Snapshot {
            panes: vec![pane("%0", "a", 0, 0, 0)],
            ..Default::default()
        };
        assert!(select(&s, None).is_empty());
    }

    #[test]
    fn selection_carries_line_counts() {
        let sel = select(&snap(), Some("work"));
        assert_eq!(sel[0], ("%1".to_string(), "work:1.0".to_string(), 500));
    }
}