fix last fix

Author: jph00

fastcore/dispatch.py

@@ -25,9 +25,9 @@ def anno_ret(func):
 cmp_instance = functools.cmp_to_key(lambda a,b: 0 if a==b else 1 if issubclass(a,b) else -1)
 
 # Cell
-def _chk_defaults(f):
+def _chk_defaults(f, ann):
     try: # Some callables don't have signatures, so ignore those errors
-        params = list(inspect.signature(f).parameters.values())[:2]
+        params = list(inspect.signature(f).parameters.values())[:min(len(ann),2)]
         if any(p.default!=inspect.Parameter.empty for p in params):
             warn(f"{f.__name__} has default params. These will be ignored.")
     except ValueError: pass
@@ -37,7 +37,7 @@ def _p2_anno(f):
     "Get the 1st 2 annotations of `f`, defaulting to `object`"
     hints = type_hints(f)
     ann = [o for n,o in hints.items() if n!='return']
-    if callable(f): _chk_defaults(f)
+    if callable(f): _chk_defaults(f, ann)
     while len(ann)<2: ann.append(object)
     return ann[:2]
 

nbs/03_dispatch.ipynb

@@ -217,9 +217,9 @@
    "outputs": [],
    "source": [
     "#export\n",
-    "def _chk_defaults(f):\n",
+    "def _chk_defaults(f, ann):\n",
     "    try: # Some callables don't have signatures, so ignore those errors\n",
-    "        params = list(inspect.signature(f).parameters.values())[:2]\n",
+    "        params = list(inspect.signature(f).parameters.values())[:min(len(ann),2)]\n",
     "        if any(p.default!=inspect.Parameter.empty for p in params):\n",
     "            warn(f\"{f.__name__} has default params. These will be ignored.\")\n",
     "    except ValueError: pass"
@@ -236,7 +236,7 @@
     "    \"Get the 1st 2 annotations of `f`, defaulting to `object`\"\n",
     "    hints = type_hints(f)\n",
     "    ann = [o for n,o in hints.items() if n!='return']\n",
-    "    if callable(f): _chk_defaults(f)\n",
+    "    if callable(f): _chk_defaults(f, ann)\n",
     "    while len(ann)<2: ann.append(object)\n",
     "    return ann[:2]"
    ]
@@ -264,19 +264,31 @@
     "test_eq(_p2_anno(_f), (int,int))\n",
     "def _f(a:int, b:str)->float: pass\n",
     "test_eq(_p2_anno(_f), (int,str))\n",
-    "test_eq(_p2_anno(attrgetter('foo')), (object,object))\n",
-    "_p2_anno(None)"
+    "test_eq(_p2_anno(attrgetter('foo')), (object,object))"
    ]
   },
   {
    "cell_type": "code",
    "execution_count": null,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "([object, object], [int, object])"
+      ]
+     },
+     "execution_count": null,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "#hide\n",
     "def _f(x:int,y:int=10): pass\n",
-    "test_warns(lambda: _p2_anno(_f))"
+    "test_warns(lambda: _p2_anno(_f))\n",
+    "def _f(x:int,y=10): pass\n",
+    "_p2_anno(None),_p2_anno(_f)"
    ]
   },
   {
@@ -856,7 +868,7 @@
     {
      "data": {
       "text/markdown": [
-       "<h4 id=\"TypeDispatch.__call__\" class=\"doc_header\"><code>TypeDispatch.__call__</code><a href=\"__main__.py#L33\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "<h4 id=\"TypeDispatch.__call__\" class=\"doc_header\"><code>TypeDispatch.__call__</code><a href=\"__main__.py#L32\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
        "\n",
        "> <code>TypeDispatch.__call__</code>(**\\*`args`**, **\\*\\*`kwargs`**)\n",
        "\n",
@@ -944,7 +956,7 @@
     {
      "data": {
       "text/markdown": [
-       "<h4 id=\"TypeDispatch.returns\" class=\"doc_header\"><code>TypeDispatch.returns</code><a href=\"__main__.py#L21\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "<h4 id=\"TypeDispatch.returns\" class=\"doc_header\"><code>TypeDispatch.returns</code><a href=\"__main__.py#L20\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
        "\n",
        "> <code>TypeDispatch.returns</code>(**`x`**)\n",
        "\n",
@@ -1110,15 +1122,6 @@
     "test_eq(f_td_test('a','b'), 'ab')"
    ]
   },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "test_warns??"
-   ]
-  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -1139,45 +1142,6 @@
     "test_warns(outer,True)"
    ]
   },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [
-    {
-     "name": "stderr",
-     "output_type": "stream",
-     "text": [
-      "/home/jhoward/anaconda3/lib/python3.7/site-packages/ipykernel_launcher.py:12: UserWarning: _test has default params. These will be ignored.\n",
-      "  if sys.path[0] == '':\n"
-     ]
-    }
-   ],
-   "source": [
-    "@typedispatch\n",
-    "def _test(x:int,y:int,z=10): return x*y*10"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "text/plain": [
-       "60"
-      ]
-     },
-     "execution_count": null,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
-   "source": [
-    "_test(3,2)"
-   ]
-  },
   {
    "cell_type": "markdown",
    "metadata": {},