Add PyTypePtr#subclass?

Author: mrkn

ext/pycall/libpython.c

@@ -94,6 +94,7 @@ pycall_init_libpython_api_table(VALUE libpython_handle)
   INIT_API_TABLE_ENTRY(_PyObject_New, required);
   INIT_API_TABLE_ENTRY(PyCallable_Check, required);
   INIT_API_TABLE_ENTRY(PyObject_IsInstance, required);
+  INIT_API_TABLE_ENTRY(PyObject_IsSubclass, required);
   INIT_API_TABLE_ENTRY2(PyObject_Hash._hash_t, PyObject_Hash, required);
   INIT_API_TABLE_ENTRY(PyObject_RichCompare, required);
   INIT_API_TABLE_ENTRY(PyObject_Call, required);

ext/pycall/pycall.c

@@ -526,6 +526,23 @@ pycall_pytypeptr_get_tp_flags(VALUE obj)
   return Qnil;
 }
 
+static VALUE
+pycall_pytypeptr_subclass_p(VALUE obj, VALUE other)
+{
+  PyObject *pyobj, *pyobj_other;
+  int res;
+
+  pyobj = get_pytypeobj_ptr(obj);
+  pyobj_other = check_get_pytypeobj_ptr(other);
+
+  res = Py_API(PyObject_IsSubclass)(pyobj, pyobj_other);
+  if (res < 0) {
+    pycall_pyerror_fetch_and_raise("PyObject_IsSubclass in pycall_pytypeptr_subclass_p");
+  }
+
+  return res ? Qtrue : Qfalse;
+}
+
 static VALUE
 pycall_pytypeptr_eqq(VALUE obj, VALUE other)
 {
@@ -2108,6 +2125,7 @@ Init_pycall(void)
   rb_define_method(cPyTypePtr, "__tp_name__", pycall_pytypeptr_get_tp_name, 0);
   rb_define_method(cPyTypePtr, "__tp_basicsize__", pycall_pytypeptr_get_tp_basicsize, 0);
   rb_define_method(cPyTypePtr, "__tp_flags__", pycall_pytypeptr_get_tp_flags, 0);
+  rb_define_method(cPyTypePtr, "subclass?", pycall_pytypeptr_subclass_p, 1);
   rb_define_method(cPyTypePtr, "===", pycall_pytypeptr_eqq, 1);
 
   /* PyCall::LibPython::API */

ext/pycall/pycall_internal.h

@@ -525,6 +525,7 @@ typedef struct {
   PyObject * (* _PyObject_New)(PyTypeObject *);
   int (* PyCallable_Check)(PyObject *);
   int (* PyObject_IsInstance)(PyObject *, PyObject *);
+  int (* PyObject_IsSubclass)(PyObject *, PyObject *);
   union {
     long      (* _long)(PyObject *);
     Py_hash_t (* _hash_t)(PyObject *);

spec/pycall/pytypeptr_spec.rb

@@ -0,0 +1,62 @@
+require 'spec_helper'
+
+module PyCall
+  ::RSpec.describe PyTypePtr do
+    describe '#subclass?(other)' do
+      subject { PyCall::List.__pyptr__ }
+
+      context 'when the value of `other` is a PyTypePtr' do
+        specify do
+          expect(subject.subclass?(PyCall.builtins.object.__pyptr__)).to eq(true)
+          expect(subject.subclass?(PyCall.builtins.dict.__pyptr__)).to eq(false)
+        end
+      end
+
+      context 'when the value of `other` is a PyPtr' do
+        specify do
+          expect { subject.subclass?(Conversion.from_ruby(42)) }.to raise_error(TypeError)
+        end
+      end
+
+      context 'when the value of `other` is a PyTypeObjectWrapper' do
+        specify do
+          expect { subject.subclass?(PyCall.builtins.object) }.to raise_error(TypeError)
+          expect { subject.subclass?(PyCall.builtins.dict)   }.to raise_error(TypeError)
+        end
+      end
+
+      context 'when the value of `other` is a Class' do
+        specify do
+          expect { subject.subclass?(Array) }.to raise_error(TypeError)
+          expect { subject.subclass?(Hash)  }.to raise_error(TypeError)
+        end
+      end
+
+      context 'when the value of `other` is an instance of other class' do
+        specify do
+          expect { subject.subclass?(12) }.to raise_error(TypeError)
+        end
+      end
+    end
+
+    describe '#<=>' do
+      pending
+    end
+
+    describe '#<' do
+      pending
+    end
+
+    describe '#>' do
+      pending
+    end
+
+    describe '#<=' do
+      pending
+    end
+
+    describe '#>=' do
+      pending
+    end
+  end
+end