Addresses: acme's ; is tested and documented

/a/;/b/ searches b from the end of a (acme's addr.c:170-171 sets ar to the
left side), and /a/,/b/ searches both from the current address; the review
asked that it be confirmed, and it held.

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

1 files changed, 12 insertions, 0 deletions

diff --git a/src/ninep/addr.zig b/src/ninep/addr.zig
index 3b29f622..0537c17a 100644
--- a/src/ninep/addr.zig
+++ b/src/ninep/addr.zig
@@ -272,6 +272,18 @@ test "an address is evaluated from the current one, as acme's are" {
     }
     // A range whose end comes before its start is sam's error.
     try testing.expectEqualStrings(e_order, th.wr(p, addr, "#10,#5").reply.ename);
+
+    // `;` evaluates its right side from its left (acme's addr.c:170-171,
+    // `ar = r`), `,` from the address the whole started at.
+    const q = try th.withFile(testing.allocator, "b a b\n");
+    defer q.deinit();
+    const qaddr = Node.of(th.serialOf(q), .addr);
+    _ = th.wr(q, qaddr, "#0");
+    try testing.expectEqual(Status.ok, th.wr(q, qaddr, "/a/;/b/").reply.status);
+    try testing.expectEqual(@as(u32, 2), q.panes[0].?.fs.addr.q0);
+    try testing.expectEqual(@as(u32, 5), q.panes[0].?.fs.addr.q1);
+    _ = th.wr(q, qaddr, "#0");
+    try testing.expectEqualStrings(e_order, th.wr(q, qaddr, "/a/,/b/").reply.ename);
 }
 
 test "regular expressions search lines as sam's do, and a search wraps" {