Allow coroutines to be decorated

hy/compiler.py

@@ -76,6 +76,9 @@ def _is_hy_builtin(name, module_name):
 
 
 _compile_table = {}
+_decoratables = (ast.FunctionDef, ast.ClassDef)
+if PY35:
+    _decoratables += (ast.AsyncFunctionDef,)
 
 
 def ast_str(foobar):
@@ -1301,8 +1304,7 @@ class HyASTCompiler(object):
     def compile_decorate_expression(self, expr):
         expr.pop(0)  # with-decorator
         fn = self.compile(expr.pop())
-        if not fn.stmts or not isinstance(fn.stmts[-1], (ast.FunctionDef,
+        if not fn.stmts or not isinstance(fn.stmts[-1], _decoratables):
-                                                         ast.ClassDef)):
             raise HyTypeError(expr, "Decorated a non-function")
         decorators, ret, _ = self._compile_collect(expr)
         fn.stmts[-1].decorator_list = decorators + fn.stmts[-1].decorator_list

tests/native_tests/py35_only_tests.hy

@@ -45,6 +45,16 @@
   (assert (= (run-coroutine coro-test) [1 2 3])))
 
 
+(defn test-decorated-defn/a []
+  (defn decorator [func] (fn/a [] (/ (await (func)) 2)))
+
+  #@(decorator
+      (defn/a coro-test []
+        (await (sleep 0))
+        42))
+  (assert (= (run-coroutine coro-test) 21)))
+
+
 (defclass AsyncWithTest []
   (defn --init-- [self val]
     (setv self.val val)