From b1df516bf1269c8230ae0e23a7ef95f9395e97a3 Mon Sep 17 00:00:00 2001
From: BLUELOVETH <blueloveTH@foxmail.com>
Date: Fri, 15 Sep 2023 17:37:07 +0800
Subject: [PATCH] add `callable`

---
 src/pocketpy.cpp         | 19 +++++++++++++++++++
 tests/99_builtin_func.py | 25 ++++++++++++++++++++++++-
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/pocketpy.cpp b/src/pocketpy.cpp
index 36315021..d43b4319 100644
--- a/src/pocketpy.cpp
+++ b/src/pocketpy.cpp
@@ -162,6 +162,17 @@ void init_builtins(VM* _vm) {
     _vm->bind_builtin_func<1>("staticmethod", [](VM* vm, ArgsView args) {
         return args[0];
     });
+    
+    _vm->bind_builtin_func<1>("callable", [](VM* vm, ArgsView args) {
+        PyObject* cls = vm->_t(args[0]);
+        Type t = PK_OBJ_GET(Type, cls);
+        if(t == vm->tp_function) return vm->True;
+        if(t == vm->tp_native_func) return vm->True;
+        if(t == vm->tp_bound_method) return vm->True;
+        if(t == vm->tp_type) return vm->True;
+        bool ok = vm->find_name_in_mro(cls, __call__) != nullptr;
+        return VAR(ok);
+    });
 
     _vm->bind_builtin_func<1>("__import__", [](VM* vm, ArgsView args) {
         const Str& name = CAST(Str&, args[0]);
@@ -1271,12 +1282,20 @@ void init_builtins(VM* _vm) {
         return VAR(func.decl->signature);
     });
 
+    // _vm->bind_property(_vm->_t(_vm->tp_function), "__call__", [](VM* vm, ArgsView args) {
+    //     return args[0];
+    // });
+
     _vm->bind_property(_vm->_t(_vm->tp_native_func), "__signature__", [](VM* vm, ArgsView args) {
         NativeFunc& func = _CAST(NativeFunc&, args[0]);
         if(func.decl != nullptr) return VAR(func.decl->signature);
         return VAR("");
     });
 
+    // _vm->bind_property(_vm->_t(_vm->tp_native_func), "__call__", [](VM* vm, ArgsView args) {
+    //     return args[0];
+    // });
+
     RangeIter::register_class(_vm, _vm->builtins);
     ArrayIter::register_class(_vm, _vm->builtins);
     StringIter::register_class(_vm, _vm->builtins);
diff --git a/tests/99_builtin_func.py b/tests/99_builtin_func.py
index 1bd0b080..d1a3ad71 100644
--- a/tests/99_builtin_func.py
+++ b/tests/99_builtin_func.py
@@ -1147,4 +1147,27 @@ assert min([
     (1, 2),
     (1, 3),
     (1, 4),
-]) == (1, 2)
\ No newline at end of file
+]) == (1, 2)
+
+
+# test callable
+assert callable(lambda: 1) is True          # function
+assert callable(1) is False                 # int
+assert callable(object) is True             # type
+assert callable(object()) is False
+assert callable([].append) is True      # bound method
+assert callable([].__getitem__) is True # bound method
+
+class A:
+    def __init__(self):
+        pass
+
+    def __call__(self):
+        pass
+
+assert callable(A) is True      # type
+assert callable(A()) is True    # instance with __call__
+assert callable(A.__call__) is True  # bound method
+assert callable(A.__init__) is True  # bound method
+assert callable(print) is True  # builtin function
+assert callable(isinstance) is True  # builtin function