Support wider use of @property decorator on CClassDef AttributeNodes (GH-3095)

* TEST: add cgetter test for pointer and pxd use
* BUG: handle more AttributeNode-with-property-decorator
* BUG: fix numpy/__init__.pxd
* ENH: add @property for ndarray.size, formatting cleanup

Cython/Compiler/ExprNodes.py

@@ -875,6 +875,8 @@ class ExprNode(Node):
         #
         src = self
         src_type = self.type
+        if src_type.is_cfunction and src_type.entry.is_cgetter:
+            src_type = src_type.return_type
 
         if self.check_for_coercion_error(dst_type, env):
             return self
@@ -3633,7 +3635,10 @@ class IndexNode(_IndexingBaseNode):
         self.nogil = env.nogil
         base_type = self.base.type
 
-        if not base_type.is_cfunction:
+        if base_type.is_cfunction:
+            if self.base.entry.is_cgetter:
+                base_type = base_type.return_type
+        else:
             self.index = self.index.analyse_types(env)
             self.original_index_type = self.index.type
 
@@ -3720,7 +3725,10 @@ class IndexNode(_IndexingBaseNode):
 
     def analyse_as_c_array(self, env, is_slice):
         base_type = self.base.type
-        self.type = base_type.base_type
+        if hasattr(self.base, 'entry') and self.base.entry.is_cgetter:
+            self.type = base_type.return_type.base_type
+        else:
+            self.type = base_type.base_type
         if is_slice:
             self.type = base_type
         elif self.index.type.is_pyobject:
@@ -3969,9 +3977,12 @@ class IndexNode(_IndexingBaseNode):
             else:
                 assert False, "unexpected base type in indexing: %s" % self.base.type
         elif self.base.type.is_cfunction:
-            return "%s<%s>" % (
-                self.base.result(),
-                ",".join([param.empty_declaration_code() for param in self.type_indices]))
+            if self.base.entry.is_cgetter:
+                index_code = "(%s[%s])"
+            else:
+                return "%s<%s>" % (
+                    self.base.result(),
+                    ",".join([param.empty_declaration_code() for param in self.type_indices]))
         elif self.base.type.is_ctuple:
             index = self.index.constant_result
             if index < 0:
@@ -12212,6 +12223,10 @@ class CmpNode(object):
         operand2 = self.operand2
         type1 = operand1.type
         type2 = operand2.type
+        if type1.is_cfunction and type1.entry.is_cgetter:
+            type1 = type1.return_type
+        if type2.is_cfunction and type2.entry.is_cgetter:
+            type2 = type2.return_type
 
         new_common_type = None
 

Cython/Compiler/Nodes.py

@@ -1767,6 +1767,11 @@ class FuncDefNode(StatNode, BlockNode):
 
     def generate_function_definitions(self, env, code):
         from . import Buffer
+
+        if self.entry.is_cgetter:
+            # no code to generate
+            return
+
         if self.return_type.is_memoryviewslice:
             from . import MemoryView
 

Cython/Compiler/ParseTreeTransforms.py

@@ -581,7 +581,9 @@ class PxdPostParse(CythonTransform, SkipDeclarations):
             err = None # allow these slots
 
         if isinstance(node, Nodes.CFuncDefNode):
-            if (u'inline' in node.modifiers and
+            if node.decorators and self.scope_type == 'cclass':
+                err = None
+            elif (u'inline' in node.modifiers and
                 self.scope_type in ('pxd', 'cclass')):
                 node.inline_in_pxd = True
                 if node.visibility != 'private':

Cython/Includes/numpy/__init__.pxd

@@ -244,14 +244,27 @@ cdef extern from "numpy/arrayobject.h":
 
         cdef:
             # Only taking a few of the most commonly used and stable fields.
-            # One should use PyArray_* macros instead to access the C fields.
             char *data
-            int ndim "nd"
-            npy_intp *shape "dimensions"
-            npy_intp *strides
-            dtype descr  # deprecated since NumPy 1.7 !
+            dtype descr
             PyObject* base
 
+            @property
+            cdef int ndim(self):
+                return PyArray_NDIM(self)
+
+            @property
+            cdef npy_intp *shape(self):
+                return PyArray_DIMS(self)
+
+            @property
+            cdef npy_intp *strides(self):
+                return PyArray_STRIDES(self)
+
+            @property
+            cdef npy_intp size(self):
+                return PyArray_SIZE(ndarray)
+
+
         # Note: This syntax (function definition in pxd files) is an
         # experimental exception made for __getbuffer__ and __releasebuffer__
         # -- the details of this may change.

tests/run/ext_attr_getter.srctree

@@ -8,8 +8,7 @@ from Cython.Compiler.Errors import CompileError
 from distutils.core import setup
 
 # force the build order
-setup(ext_modules= cythonize("foo_extension.pyx", language_level=3))
-
+setup(ext_modules = cythonize("foo_extension.pyx", language_level=3))
 setup(ext_modules = cythonize("getter[0-9].pyx", language_level=3))
 
 for name in ("getter_fail0.pyx", "getter_fail1.pyx"):
@@ -32,6 +31,7 @@ typedef struct {
     int f0;
     int f1;
     int f2;
+    int v[10];
 } FooStructNominal;
 
 typedef struct {
@@ -58,6 +58,11 @@ int PyFoo_Get2F(FooStructOpaque *f)
     return PyFoo_GET2M(f);
 }
 
+int *PyFoo_GetV(FooStructOpaque *f)
+{
+    return ((FooStructNominal*)f)->v;
+}
+
 #ifdef __cplusplus
 }
 #endif
@@ -66,6 +71,7 @@ int PyFoo_Get2F(FooStructOpaque *f)
 
 cdef class Foo:
     cdef public int _field0, _field1, _field2;
+    cdef public int _vector[10];
 
     @property
     def field0(self):
@@ -79,10 +85,22 @@ cdef class Foo:
     def field2(self):
         return self._field2
 
-    def __init__(self, f0, f1, f2):
+    def __init__(self, f0, f1, f2, vec=None):
+        if vec is None:
+            vec = ()
+        if not isinstance(vec, tuple):
+            raise ValueError("v must be None or a tuple")
         self._field0 = f0
         self._field1 = f1
         self._field2 = f2
+        i = 0
+        for v in vec:
+            self._vector[i] = v
+            if i > 9:
+                break
+            i += 1
+        for j in range(i,10):
+            self._vector[j] = 0
 
 # A pure-python class that disallows direct access to fields
 class OpaqueFoo(Foo):
@@ -116,7 +134,7 @@ def sum(Foo f):
     # notices the alias and replaces the __getattr__ in c by f->f0 anyway
     return f.field0 + f.field1 + f.field2
 
-######## getter1.pyx ########
+######## getter.pxd ########
 
 # Access base Foo fields from C via getter functions
 
@@ -135,15 +153,29 @@ cdef extern from "foo.h":
         cdef int fieldM2(self):
             return PyFoo_GET2M(self)
 
+        @property
+        cdef int *vector(self):
+            return PyFoo_GetV(self)
+
     int PyFoo_GET0M(Foo);  # this is actually a macro !
     int PyFoo_Get1F(Foo);
     int PyFoo_GET2M(Foo);  # this is actually a macro !
+    int *PyFoo_GetV(Foo);
 
-def sum(Foo f):
+######## getter1.pyx ########
+
+cimport getter
+
+def sum(getter.Foo f):
     # Note - not a cdef function but compiling the f.__getattr__('field0')
     # notices the getter and replaces the __getattr__ in c by PyFoo_GET anyway
     return f.fieldM0 + f.fieldF1 + f.fieldM2
 
+def check_10(getter.Foo f):
+    return f.fieldF1 != 10
+
+def vec0(getter.Foo f):
+        return f.vector[0]
 
 ######## getter_fail0.pyx ########
 
@@ -203,7 +235,7 @@ except AttributeError as e:
 # - C accesses the fields through getter calls (maybe macros)
 # - Python accesses the fields through attribute lookup
 
-opaque_foo = foo_extension.OpaqueFoo(23, 123, 1023)
+opaque_foo = foo_extension.OpaqueFoo(23, 123, 1023, (1, 2, 3))
 
 opaque_ret = getter1.sum(opaque_foo)
 assert opaque_ret == ret