matcher: bugfix: bad stray code in @[...] matcher.

* share/txr/stdlib/match.tl (compile-dwim-predicate-match): In
he one-argument case, there is stray code referencing
var-match.test-expr, which blows up. This is hit by exactly
the one example in the documentation that was not added
as a test case.

* tests/011/patmatch.tl: Add test case from doc.

1 files changed, 4 insertions, 0 deletions

diff --git a/tests/011/patmatch.tl b/tests/011/patmatch.tl
index 7768e89b..347af4eb 100644
--- a/tests/011/patmatch.tl
+++ b/tests/011/patmatch.tl
@@ -161,6 +161,10 @@
 (test (when-match (rcons @a @b) '(rcons 1 2) (list a b)) (1 2))
 
 (test (let ((h #H(() (a 1) (b 2))))
+        (when-match @[h x] 'a x))
+      a)
+
+(test (let ((h #H(() (a 1) (b 2))))
         (when-match @[h x y] 'a (list x y)))
       (a 1))