Add sq_contains, test and documentation.

Author: paulross

doc/sphinx/source/new_types.rst

@@ -562,7 +562,8 @@ The Sequence Function Table
      - ``int (*objobjproc)(PyObject*, PyObject*)``
      - Returns non-zero if the sequence contains the given object.
        Used by `PySequence_Contains()`_.
-       This slot may be left to NULL, in this case PySequence_Contains() simply traverses the sequence until it finds a match.
+       This slot may be left to NULL, in this case PySequence_Contains() simply traverses the sequence until it
+       finds a match.
    * - `sq_inplace_concat`_
      - `binaryfunc`_
      - ``PyObject *(*binaryfunc)(PyObject*, PyObject*)``
@@ -1157,6 +1158,91 @@ Deleting a value with an out of range index:
         assert err.value.args[0] == expected
 
 
+-------------------
+``sq_ass_contains``
+-------------------
+
+.. list-table:: Sequence Methods: ``sq_ass_contains``
+   :widths: 20 80
+   :header-rows: 0
+
+   * - Member
+     - `sq_ass_contains`_
+   * - Function type
+     - `objobjproc`_
+   * - Function signature
+     - ``int (*objobjproc)(PyObject*, PyObject*)``
+   * - Description
+     - Returns non-zero if the sequence contains the given object.
+       If an item in o is equal to value, return 1, otherwise return 0. On error, return -1.
+       This is equivalent to the Python expression ``value in o``.
+       Used by `PySequence_Contains()`_.
+       This slot may be left to NULL, in this case `PySequence_Contains()`_ simply traverses the sequence until it
+       finds a match.
+
+Implementation
+--------------
+
+In ``src/cpy/Object/cSeqObject.c``:
+
+.. code-block:: c
+
+    /** If an item in self is equal to value, return 1, otherwise return 0.
+     * On error, return -1. */
+    static int
+    SequenceLongObject_sq_contains(PyObject *self, PyObject *value) {
+        fprintf(
+                stdout, "%s()#%d: self=%p value=%p\n",
+                __FUNCTION__, __LINE__, (void *) self, (void *) value
+        );
+        if (!PyLong_Check(value)) {
+            /* Alternates: Could raise TypeError or return -1.
+             * Here we act benignly! */
+            return 0;
+        }
+        long c_value = PyLong_AsLong(value);
+        /* For convenience. */
+        SequenceLongObject *self_as_slo = (SequenceLongObject *) self;
+        for (Py_ssize_t i = 0; i < SequenceLongObject_sq_length(self); ++i) {
+            if (self_as_slo->array_long[i] == c_value) {
+                return 1;
+            }
+        }
+        return 0;
+    }
+
+.. note::
+
+    Whilst ``SequenceLongObject_sq_contains()`` returns 0 or 1 Python code such as ``value in obj`` converts this to
+    ``False`` and ``True`` respectively
+
+Tests
+--------------
+
+Tests are in ``tests/unit/test_c_seqobject.py``:
+
+.. code-block:: python
+
+    from cPyExtPatt import cSeqObject
+
+    @pytest.mark.parametrize(
+        'initial_sequence, value, expected',
+        (
+                (
+                        [7, ], 0, False,
+                ),
+                (
+                        [7, ], 7, True,
+                ),
+                (
+                        [1, 4, 7, ], 7, True,
+                ),
+        )
+    )
+    def test_SequenceLongObject_contains(initial_sequence, value, expected):
+        obj = cSeqObject.SequenceLongObject(initial_sequence)
+        result = value in obj
+        assert result == expected
 
 
 

src/cpy/Object/cSeqObject.c

@@ -305,13 +305,41 @@ SequenceLongObject_sq_ass_item(PyObject *self, Py_ssize_t index, PyObject *value
     return 0;
 }
 
+/**
+ * If an item in self is equal to value, return 1, otherwise return 0. On error, return -1.
+ * @param self
+ * @param value
+ * @return
+ */
+static int
+SequenceLongObject_sq_contains(PyObject *self, PyObject *value) {
+    fprintf(
+            stdout, "%s()#%d: self=%p value=%p\n",
+            __FUNCTION__, __LINE__, (void *) self, (void *) value
+    );
+    if (!PyLong_Check(value)) {
+        /* Alternates: Could raise TypeError or return -1.
+         * Here we act benignly! */
+        return 0;
+    }
+    long c_value = PyLong_AsLong(value);
+    /* For convenience. */
+    SequenceLongObject *self_as_slo = (SequenceLongObject *) self;
+    for (Py_ssize_t i = 0; i < SequenceLongObject_sq_length(self); ++i) {
+        if (self_as_slo->array_long[i] == c_value) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
 static PySequenceMethods SequenceLongObject_sequence_methods = {
         .sq_length = (lenfunc)SequenceLongObject_sq_length,
         .sq_concat = (binaryfunc)SequenceLongObject_sq_concat,
         .sq_repeat = (ssizeargfunc)SequenceLongObject_sq_repeat,
         .sq_item = (ssizeargfunc)SequenceLongObject_sq_item,
         .sq_ass_item = (ssizeobjargproc)SequenceLongObject_sq_ass_item,
-        .sq_contains = (objobjproc)NULL,
+        .sq_contains = (objobjproc)SequenceLongObject_sq_contains,
         .sq_inplace_concat = (binaryfunc)NULL,
         .sq_inplace_repeat = (ssizeargfunc)NULL,
 };

tests/unit/test_c_seqobject.py

@@ -16,6 +16,7 @@ def test_SequenceLongObject_dir_pre_311():
     assert result == [
         '__add__',
         '__class__',
+        '__contains__',
         '__delattr__',
         '__delitem__',
         '__dir__',
@@ -53,6 +54,7 @@ def test_SequenceLongObject_dir_311_plus():
     assert result == [
         '__add__',
         '__class__',
+        '__contains__',
         '__delattr__',
         '__delitem__',
         '__dir__',
@@ -287,6 +289,26 @@ def test_SequenceLongObject_delitem_raises(initial_sequence, index, expected):
         del obj[index]
     assert err.value.args[0] == expected
 
+
+@pytest.mark.parametrize(
+    'initial_sequence, value, expected',
+    (
+            (
+                    [7, ], 0, False,
+            ),
+            (
+                    [7, ], 7, True,
+            ),
+            (
+                    [1, 4, 7, ], 7, True,
+            ),
+    )
+)
+def test_SequenceLongObject_contains(initial_sequence, value, expected):
+    obj = cSeqObject.SequenceLongObject(initial_sequence)
+    result = value in obj
+    assert result == expected
+
 # @pytest.mark.parametrize(
 #     'initial_sequence, index, value, expected',
 #     (