Mount dials its peer at once and fails if none answers; a peer out of reach is said as `dial failed: <reason>`

Mount took any well-formed dial and nothing was found out until the
first look through it, which then said `look: look: dial`. Mount now
probes the peer (version, attach, its root) with the turn out, and fails
its write, mounting nothing, when none answers; the dial errors read as
words, `no answer`, `timed out`, `hung up`, and a look through a peer
gone since names its path: `look: /n/peer/f: dial failed: no answer`.

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

1 files changed, 9 insertions, 3 deletions

diff --git a/test/fs_namespace.zig b/test/fs_namespace.zig
index 2f78ca1a..bd620c2d 100644
--- a/test/fs_namespace.zig
+++ b/test/fs_namespace.zig
@@ -6,9 +6,15 @@ test "runtime Mount and Unmount copy command arguments and change Look resolutio
     const gpa = std.testing.allocator;
     const p = try pardes.Pardes.init(gpa, .{ .tty_only = true });
     defer p.deinit();
-    var command = "Mount peer /tmp/a socket.sock".*;
-    try std.testing.expect(p.executeBuiltinLine(0, &command));
-    @memset(&command, 'x');
+    // No peer answers at the dial: Mount mounts nothing (it dials first).
+    try std.testing.expect(p.executeBuiltinLine(0, "Mount peer /tmp/a socket.sock"));
+    try std.testing.expectEqual(@as(usize, 0), p.fs.mounts.items.len);
+    // Mounted (as one that answered is), its arguments are copies.
+    var name = "peer".*;
+    var dial = "/tmp/a socket.sock".*;
+    try p.fs.mount(gpa, &name, &dial);
+    @memset(&name, 'x');
+    @memset(&dial, 'x');
     try std.testing.expectEqual(@as(usize, 1), p.fs.mounts.items.len);
     try std.testing.expectEqualStrings("peer", p.fs.mounts.items[0].name);
     try std.testing.expectEqualStrings("/tmp/a socket.sock", p.fs.mounts.items[0].dial);