Disallow &key in macros

hy/compiler.py

@@ -2428,7 +2428,7 @@ class HyASTCompiler(object):
             raise HyTypeError(name, ("received a `%s' instead of a symbol "
                                      "for macro name" % type(name).__name__))
         name = HyString(name).replace(name)
-        for kw in ("&kwonly", "&kwargs"):
+        for kw in ("&kwonly", "&kwargs", "&key"):
             if kw in expression[0]:
                 raise HyTypeError(name, "macros cannot use %s" % kw)
         new_expression = HyExpression([

tests/native_tests/native_macros.hy

@@ -51,7 +51,7 @@
   (foo x y))
 
 (defn test-macro-kw []
-  "NATIVE: test that an error is raised when &kwonly or &kwargs is used in a macro"
+  "NATIVE: test that an error is raised when &kwonly, &kwargs, or &key is used in a macro"
   (try
     (eval '(defmacro f [&kwonly a b]))
     (except [e HyTypeError]
@@ -62,6 +62,12 @@
     (eval '(defmacro f [&kwargs kw]))
     (except [e HyTypeError]
       (assert (= e.message "macros cannot use &kwargs")))
+    (else (assert false)))
+
+  (try
+    (eval '(defmacro f [&key {"kw" "xyz"}]))
+    (except [e HyTypeError]
+      (assert (= e.message "macros cannot use &key")))
     (else (assert false))))
 
 (defn test-fn-calling-macro []