Mount dials: a relative socket path is a bad dial address, a socket path not there says no such socket (ENOENT), and the hint says tcp! takes a numeric address

`Mount peer rel/x.sock` dialled relative to wherever the editor ran;
`Mount peer unix!/nonexistent` said `dial failed: no answer` (EIO); and
the hint offered `tcp!host!port` where only a numeric address is taken.

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

1 files changed, 20 insertions, 4 deletions

diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index 4fb5bf41..06eb8cdd 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -1363,8 +1363,8 @@ test "the root ctl reads the settings as a write takes them, and takes the sessi
     // A builtin that fails as it runs fails the write, quoting its error and
     // its line; the lines before it have taken effect, as in acme.
     const failed = wr(p, root_ctl, "Verbose on\nMount x /tmp/pardes-no-such-sock-zz\nVerbose off");
-    try testing.expectEqual(E.IO, failed.errno());
-    try testing.expectStringStartsWith(failed.reply.ename, "Mount x /tmp/pardes-no-such-sock-zz: dial failed");
+    try testing.expectEqual(E.NOENT, failed.errno());
+    try testing.expectStringStartsWith(failed.reply.ename, "Mount x: /tmp/pardes-no-such-sock-zz: no such socket");
     try testing.expect(p.settings.verbose);
     try testing.expect(!p.fs.no_prompt);
     try testing.expectEqual(Status.ok, wr(p, root_ctl, "Verbose off").reply.status);
@@ -2458,9 +2458,14 @@ test "Mount dials its peer and fails, mounting nothing, when none answers; a loo
     defer p.deinit();
     const root_ctl = @intFromEnum(tree.TopFile.ctl);
     const dead = "/tmp/pardes-test-no-such-peer.sock";
-    const refused = wr(p, root_ctl, "Mount dead " ++ dead ++ "\n");
+    // A socket path not there is said so; one there that does not answer
+    // (a directory here) is a dial that failed.
+    const missing = wr(p, root_ctl, "Mount dead " ++ dead ++ "\n");
+    try testing.expectEqual(E.NOENT, missing.errno());
+    try testing.expectEqualStrings("Mount dead: " ++ dead ++ ": no such socket", missing.reply.ename);
+    const refused = wr(p, root_ctl, "Mount dead /tmp\n");
     try testing.expectEqual(E.IO, refused.errno());
-    try testing.expectEqualStrings("Mount dead " ++ dead ++ ": dial failed: no answer", refused.reply.ename);
+    try testing.expectEqualStrings("Mount dead /tmp: dial failed: no answer", refused.reply.ename);
     try testing.expectEqual(@as(usize, 0), p.fs.mounts.items.len);
     // A pane of a peer gone since: get says so too.
     try p.fs.mounts.append(p.gpa, .{ .name = try p.gpa.dupe(u8, "away"), .dial = try p.gpa.dupe(u8, dead) });
@@ -4438,3 +4443,14 @@ test "an unsaved pane from a dump that says nothing of its disk asks at its firs
     pardes.exec.saveFile(p, id);
     try testing.expect(th.logHas(p, "modified on disk since read (Save again to overwrite)"));
 }
+
+test "a Mount of a socket path that is not there says no such socket, ENOENT" {
+    if (comptime !pardes.hosted) return;
+    const p = try withFile(testing.allocator, "x\n");
+    defer p.deinit();
+    const r = wr(p, @intFromEnum(tree.TopFile.ctl), "Mount peer unix!/tmp/pardes-surely-no-socket\n");
+    try testing.expectEqual(E.NOENT, r.errno());
+    try testing.expect(std.mem.indexOf(u8, r.reply.ename, "no such socket") != null);
+    try testing.expectEqual(@as(usize, 0), p.fs.mounts.items.len);
+    try testing.expectEqual(E.INVAL, wr(p, @intFromEnum(tree.TopFile.ctl), "Mount peer rel/x.sock\n").errno());
+}