Add RingBuffer.reset() method

Signed-off-by: Elijah Shaw-Rutschman <elijahr@gmail.com>

Author: elijahr

README.md

@@ -142,5 +142,8 @@ Pull requests are welcome, please file any issues you encounter.
 
 ## Changelog
 
+### v2.4.0 2020-03-23
+* Added `RingBuffer.reset()` method for .
+
 ### v2.3.0 2020-03-22
-* Added `concatenate` function for joining multiple Cython arrays.
+* Added `concatenate` function for joining multiple arbitrary Python objects that support the buffer protocol.

setup.py

@@ -128,7 +128,7 @@ def get_ext_modules():
 
 setup(
     name='ringbuf',
-    version='2.3.0',
+    version='2.4.0',
     description='A lock-free ring buffer for Python and Cython.',
     long_description=get_readme(),
     long_description_content_type="text/markdown",

src/ringbuf/boost.pxd

@@ -28,8 +28,12 @@ cdef extern from '<boost/lockfree/spsc_queue.hpp>' namespace 'boost::lockfree' n
         # get write space to write elements
         size_t write_available() const
 
+        # return true, if implementation is lock-free
         libcpp.bool is_lock_free()
 
+        # reset the ringbuffer
+        void reset()
+
 
 cdef extern from *:
     spsc_queue[char]* void_ptr_to_spsc_queue_char_ptr 'static_cast<boost::lockfree::spsc_queue<char>*>' (void*) nogil except NULL

src/ringbuf/ringbuf.pyx

@@ -114,6 +114,9 @@ cdef class RingBuffer:
     def is_lock_free(self) -> bool:
         return self.queue.is_lock_free()
 
+    def reset(self) -> None:
+        self.queue.reset()
+
     cdef void* queue_void_ptr(self):
         return spsc_queue_char_ptr_to_void_ptr(self.queue)
 

test.py

@@ -38,10 +38,11 @@ def expected(request):
     return request.param
 
 
-def test_push_pop(expected):
+def test_ringbuffer_push_pop(expected):
     capacity = expected.size
 
     buffer = RingBuffer(format=expected.dtype.char, capacity=capacity)
+    assert buffer.capacity == capacity
     assert buffer.is_lock_free
 
     assert buffer.read_available == 0
@@ -93,21 +94,28 @@ def test_push_pop(expected):
         expected)
 
 
-def test_underflow():
+def test_ringbuffer_underflow():
     buffer = RingBuffer(format='b', capacity=1)
     assert buffer.pop(1) is None
 
 
-def test_overflow():
+def test_ringbuffer_overflow():
     buffer = RingBuffer(format='B', capacity=7)
     remaining = buffer.push(b'spam')
     assert remaining is None
     remaining = buffer.push(b'eggs')
     assert bytes(remaining) == b's'
-    assert bytes(buffer.pop(buffer.capacity)) == b'spamegg'
+    assert bytes(buffer.pop(7)) == b'spamegg'
 
 
-def test_invalid():
+def test_ringbuffer_reset():
+    buffer = RingBuffer(format='B', capacity=5)
+    buffer.push(b'hello')
+    buffer.reset()
+    assert buffer.pop(5) is None
+
+
+def test_ringbuffer_invalid():
     with pytest.raises(ValueError):
         RingBuffer(format='B', capacity=0)