Make apply api-compatible with python (args is not mandatory)

hy/compiler.py

@@ -1255,35 +1255,33 @@ class HyASTCompiler(object):
 
         return ret
 
-    # apply only needs to be defined for python3
+    @builds("apply")
-    if sys.version_info[0] >= 3:
+    @checkargs(min=1, max=3)
-        @builds("apply")
+    def compile_apply_expression(self, expr):
-        @checkargs(min=2, max=3)
+        expr.pop(0)  # apply
-        def compile_apply_expression(self, expr):
+        call = self.compile(expr.pop(0))
-            expr.pop(0)  # apply
+        call = ast.Call(func=call.expr,
-            call = self.compile(expr.pop(0))
+                        args=[],
-            call = ast.Call(func=call.expr,
+                        keywords=[],
-                            args=[],
+                        starargs=None,
-                            keywords=[],
+                        kwargs=None,
-                            starargs=None,
+                        lineno=expr.start_line,
-                            kwargs=None,
+                        col_offset=expr.start_column)
-                            lineno=expr.start_line,
+        ret = call
-                            col_offset=expr.start_column)
-            ret = call
 
-            #add star args if any
+        if expr:
             stargs = expr.pop(0)
             if stargs is not None:
                 stargs = self.compile(stargs)
                 call.starargs = stargs.force_expr
                 ret = stargs + ret
 
-            if expr != []:
+        if expr:
-                kwargs = self.compile(expr.pop(0))
+            kwargs = self.compile(expr.pop(0))
-                call.kwargs = kwargs.force_expr
+            call.kwargs = kwargs.force_expr
-                ret = kwargs + ret
+            ret = kwargs + ret
 
-            return ret
+        return ret
 
     @builds("not")
     @builds("~")

tests/native_tests/language.hy

@@ -168,7 +168,9 @@
   (assert (= (apply sumit [1] {"b" 2 "c" 3}) 6))
   (assert (= (apply sumit [1 2 2]) 5))
   (assert (= (apply sumit [] {"a" 1 "b" 1 "c" 2}) 4))
-  (assert (= (apply sumit ((fn [] [1 1])) {"c" 1}) 3)))
+  (assert (= (apply sumit ((fn [] [1 1])) {"c" 1}) 3))
+  (defn noargs [] [1 2 3])
+  (assert (= (apply noargs) [1 2 3])))
 
 (defn test-dotted []
   "NATIVE: test dotted invocation"