From 4840a9664526980d20bffb22c6266a38ce216994 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adri=C3=A0=20Arrufat?= <adria.arrufat@gmail.com>
Date: Thu, 23 Jul 2026 12:16:19 +0200
Subject: [PATCH] cli: fix help pager broken by lp.io's failing allocator

std.Io.Threaded.init_single_threaded sets .allocator = .failing, which
spawnPosix uses to build the child's argv/env, so
std.process.spawn(lp.io, ...) always returns OutOfMemory and printPaged
silently fell back to plain output. Spawn the pager through a local
Threaded instance with a real allocator and the real environ (the
single-threaded one is empty, breaking PATH lookup of the less
fallback).
---
 src/Config.zig | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/Config.zig b/src/Config.zig
index 9609642b0..fbdfd9553 100644
--- a/src/Config.zig
+++ b/src/Config.zig
@@ -922,22 +922,27 @@ fn printPaged(allocator: Allocator, text: []const u8) void {
     var environ_map = lp.environMap(allocator) catch return printPlain(text);
     defer environ_map.deinit();
 
-    var child = std.process.spawn(lp.io, .{
+    // lp.io cannot spawn children: failing allocator, empty environ (no PATH).
+    var pager_threaded: std.Io.Threaded = .init(allocator, .{ .environ = lp.environ() });
+    defer pager_threaded.deinit();
+    const pager_io = pager_threaded.io();
+
+    var child = std.process.spawn(pager_io, .{
         .argv = argv,
         .environ_map = &environ_map,
         .stdin = .pipe,
     }) catch return printPlain(text);
 
     if (child.stdin) |stdin| {
-        var writer = stdin.writerStreaming(lp.io, &.{});
+        var writer = stdin.writerStreaming(pager_io, &.{});
         // A write error here is the pager exiting early (user quit, or the
         // command failed) — wait() below decides which.
         writer.interface.writeAll(text) catch {};
-        stdin.close(lp.io);
+        stdin.close(pager_io);
         child.stdin = null;
     }
 
-    const term_result = child.wait(lp.io) catch return printPlain(text);
+    const term_result = child.wait(pager_io) catch return printPlain(text);
     const clean_exit = term_result == .exited and term_result.exited == 0;
     // Quitting the pager early is still exit 0; a non-zero exit means the
     // pager failed (e.g. $PAGER not found) and the help was never shown.