pardes - reads stdin into a +Pager pane, and is a terminal's PAGER and GIT_PAGER, Pager pardes|off to opt out; command panes page through cat

A paging command in a terminal, or run through its pty/run, sat in
less, and a pty/run never answered. `pardes -` now reads stdin to its
end, strips terminal escapes (colour, OSC, overstrike), and shows it:
inside a session as a clean <cwd>/+Pager pane made through pane/new and
back at once, outside one as a new editor whose first pane it is, as
`vim -` does. A terminal's shell gets PAGER and GIT_PAGER set to this
pardes's own path and `-` where the user's environment sets neither;
`Pager off`, a setting in /ctl, init and DumpConfig, leaves terminals
started after it to the environment. A command pane's one-shot shell
keeps cat, its output being a pane already.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 16 insertions, 0 deletions

diff --git a/src/pardes.zig b/src/pardes.zig
index 47ebf8fa..aa2c252c 100644
--- a/src/pardes.zig
+++ b/src/pardes.zig
@@ -4180,6 +4180,8 @@ pub const Boot = enum {
     document,
     /// a Look that found nothing: reported, not opened
     missing,
+    /// `pardes -`: stdin's text in a +Pager pane, as `vim -` shows it
+    stdin,
     /// the firmware's boot buffer, the only pane a board has
     embedded,
     /// the bare tty startup: one shell in raw tty mode, with an empty text
@@ -4196,6 +4198,7 @@ pub const Boot = enum {
         if (opts.boot) |named| return named;
         if (opts.file != null) return .document;
         if (opts.missing != null) return .missing;
+        if (opts.stdin_text != null) return .stdin;
         if (comptime platform == .esp32p4) return .embedded;
         if (opts.tty_only) return .tty_shell;
         // ponytail: 1 and 3 are the only shell counts anyone asked for
@@ -4215,6 +4218,8 @@ pub const Options = struct {
     file: ?[]const u8 = null,
     file_line: usize = 0,
     missing: ?struct { word: []const u8, dir: []const u8 } = null,
+    /// `pardes -`: stdin, its escapes stripped, for a +Pager pane at boot.
+    stdin_text: ?[]const u8 = null,
     tty_toggle: u21 = config.tty_toggle_default,
     /// load a dump of another instance instead of spawning shells (acme -l)
     load_path: ?[]const u8 = null,
@@ -4626,6 +4631,17 @@ pub const Pardes = struct {
                 _ = try panes.Output.open(p, 0, missing.dir, .errors, "", content);
                 p.oneColumn();
             },
+            .stdin => {
+                const content = try gpa.dupe(u8, opts.stdin_text.?);
+                errdefer gpa.free(content);
+                const dir = p.sessionDir();
+                const shown = try panes.Output.open(p, 0, dir, .{ .cmd = .New }, "", content);
+                // Named +Pager, as `pardes -` inside a session names its pane.
+                const named = try std.fs.path.join(gpa, &.{ dir, "+Pager" });
+                gpa.free(shown.file.?.path);
+                shown.file.?.path = named;
+                p.oneColumn();
+            },
             .embedded => {
                 const content = try p.gpa.dupe(u8, boot_buffer);
                 errdefer p.gpa.free(content);