Expose rpds.Queue.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rpds-py"
-version = "0.13.2"
+version = "0.14.0"
 edition = "2021"
 
 [lib]

src/lib.rs

@@ -6,7 +6,9 @@ use pyo3::pyclass::CompareOp;
 use pyo3::types::{PyDict, PyIterator, PyTuple, PyType};
 use pyo3::{exceptions::PyKeyError, types::PyMapping};
 use pyo3::{prelude::*, AsPyPointer, PyTypeInfo};
-use rpds::{HashTrieMap, HashTrieMapSync, HashTrieSet, HashTrieSetSync, List, ListSync};
+use rpds::{
+    HashTrieMap, HashTrieMapSync, HashTrieSet, HashTrieSetSync, List, ListSync, Queue, QueueSync,
+};
 
 #[derive(Clone, Debug)]
 struct Key {
@@ -618,12 +620,130 @@ impl ListIterator {
     }
 }
 
+#[repr(transparent)]
+#[pyclass(name = "Queue", module = "rpds", frozen, sequence)]
+struct QueuePy {
+    inner: QueueSync<PyObject>,
+}
+
+impl From<QueueSync<PyObject>> for QueuePy {
+    fn from(elements: QueueSync<PyObject>) -> Self {
+        QueuePy { inner: elements }
+    }
+}
+
+impl<'source> FromPyObject<'source> for QueuePy {
+    fn extract(ob: &'source PyAny) -> PyResult<Self> {
+        let mut ret = Queue::new_sync();
+        for each in ob.iter()? {
+            ret.enqueue_mut(each?.extract()?);
+        }
+        Ok(QueuePy { inner: ret })
+    }
+}
+
+#[pymethods]
+impl QueuePy {
+    #[new]
+    #[pyo3(signature = (*elements))]
+    fn init(elements: &PyTuple, py: Python<'_>) -> PyResult<Self> {
+        let mut ret: QueuePy;
+        if elements.len() == 1 {
+            ret = elements.get_item(0)?.extract()?;
+        } else {
+            ret = QueuePy {
+                inner: Queue::new_sync(),
+            };
+            if elements.len() > 1 {
+                for each in elements {
+                    ret.inner.enqueue_mut(each.into_py(py));
+                }
+            }
+        }
+        Ok(ret)
+    }
+
+    fn __eq__(&self, other: &Self, py: Python<'_>) -> bool {
+        (self.inner.len() == other.inner.len())
+            && self
+                .inner
+                .iter()
+                .zip(other.inner.iter())
+                .map(|(e1, e2)| PyAny::eq(e1.extract(py)?, e2))
+                .all(|r| r.unwrap_or(false))
+    }
+
+    fn __ne__(&self, other: &Self, py: Python<'_>) -> bool {
+        (self.inner.len() != other.inner.len())
+            || self
+                .inner
+                .iter()
+                .zip(other.inner.iter())
+                .map(|(e1, e2)| PyAny::ne(e1.extract(py)?, e2))
+                .any(|r| r.unwrap_or(true))
+    }
+
+    fn __iter__(slf: PyRef<'_, Self>) -> PyResult<Py<ListIterator>> {
+        let iter = slf
+            .inner
+            .iter()
+            .map(|k| k.to_owned())
+            .collect::<Vec<_>>()
+            .into_iter();
+        Py::new(slf.py(), ListIterator { inner: iter })
+    }
+
+    fn __len__(&self) -> usize {
+        self.inner.len()
+    }
+
+    fn __repr__(&self, py: Python) -> String {
+        let contents = self.inner.into_iter().map(|k| {
+            k.clone()
+                .into_py(py)
+                .call_method0(py, "__repr__")
+                .and_then(|r| r.extract(py))
+                .unwrap_or("<repr failed>".to_owned())
+        });
+        format!("Queue([{}])", contents.collect::<Vec<_>>().join(", "))
+    }
+
+    #[getter]
+    fn peek(&self) -> PyResult<PyObject> {
+        if let Some(peeked) = self.inner.peek() {
+            Ok(peeked.to_owned())
+        } else {
+            Err(PyIndexError::new_err("peeked an empty queue"))
+        }
+    }
+
+    #[getter]
+    fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
+
+    fn enqueue(&self, value: &PyAny) -> Self {
+        QueuePy {
+            inner: self.inner.enqueue(value.into()),
+        }
+    }
+
+    fn dequeue(&self) -> PyResult<QueuePy> {
+        if let Some(inner) = self.inner.dequeue() {
+            Ok(QueuePy { inner })
+        } else {
+            Err(PyIndexError::new_err("dequeued an empty queue"))
+        }
+    }
+}
+
 #[pymodule]
 #[pyo3(name = "rpds")]
 fn rpds_py(py: Python, m: &PyModule) -> PyResult<()> {
     m.add_class::<HashTrieMapPy>()?;
     PyMapping::register::<HashTrieMapPy>(py)?;
     m.add_class::<HashTrieSetPy>()?;
     m.add_class::<ListPy>()?;
+    m.add_class::<QueuePy>()?;
     Ok(())
 }

tests/test_queue.py

@@ -0,0 +1,133 @@
+"""
+Modified from the pyrsistent test suite.
+
+Pre-modification, these were MIT licensed, and are copyright:
+
+    Copyright (c) 2022 Tobias Gustafsson
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation
+    files (the "Software"), to deal in the Software without
+    restriction, including without limitation the rights to use,
+    copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following
+    conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+    OTHER DEALINGS IN THE SOFTWARE.
+"""
+import pytest
+
+from rpds import Queue
+
+HASH_MSG = "Not sure Queue implements Hash, it has mutable methods"
+
+
+def test_literalish_works():
+    assert Queue(1, 2, 3) == Queue([1, 2, 3])
+
+
+def test_peek_dequeue():
+    pl = Queue([1, 2])
+    assert pl.peek == 1
+    assert pl.dequeue().peek == 2
+    assert pl.dequeue().dequeue().is_empty
+    with pytest.raises(IndexError):
+        pl.dequeue().dequeue().dequeue()
+
+
+def test_instantiate_large_list():
+    assert Queue(range(1000)).peek == 0
+
+
+def test_iteration():
+    assert list(Queue()) == []
+    assert list(Queue([1, 2, 3])) == [1, 2, 3]
+
+
+def test_enqueue():
+    assert Queue([1, 2, 3]).enqueue(4) == Queue([1, 2, 3, 4])
+
+
+def test_enqueue_empty_list():
+    assert Queue().enqueue(0) == Queue([0])
+
+
+def test_truthiness():
+    assert Queue([1])
+    assert not Queue()
+
+
+def test_len():
+    assert len(Queue([1, 2, 3])) == 3
+    assert len(Queue()) == 0
+
+
+def test_peek_illegal_on_empty_list():
+    with pytest.raises(IndexError):
+        Queue().peek
+
+
+def test_inequality():
+    assert Queue([1, 2]) != Queue([1, 3])
+    assert Queue([1, 2]) != Queue([1, 2, 3])
+    assert Queue() != Queue([1, 2, 3])
+
+
+def test_repr():
+    assert str(Queue()) == "Queue([])"
+    assert str(Queue([1, 2, 3])) in "Queue([1, 2, 3])"
+
+
+@pytest.mark.xfail(reason=HASH_MSG)
+def test_hashing():
+    assert hash(Queue([1, 2])) == hash(Queue([1, 2]))
+    assert hash(Queue([1, 2])) != hash(Queue([2, 1]))
+
+
+def test_sequence():
+    m = Queue("asdf")
+    assert m == Queue(["a", "s", "d", "f"])
+
+
+# Non-pyrsistent-test-suite tests
+
+
+def test_dequeue():
+    assert Queue([1, 2, 3]).dequeue() == Queue([2, 3])
+
+
+def test_dequeue_empty():
+    """
+    rpds itself returns an Option<Queue> here but we try IndexError instead.
+    """
+    with pytest.raises(IndexError):
+        Queue([]).dequeue()
+
+
+def test_more_eq():
+    o = object()
+
+    assert Queue([o, o]) == Queue([o, o])
+    assert Queue([o]) == Queue([o])
+    assert Queue() == Queue([])
+    assert not (Queue([1, 2]) == Queue([1, 3]))
+    assert not (Queue([o]) == Queue([o, o]))
+    assert not (Queue([]) == Queue([o]))
+
+    assert Queue([1, 2]) != Queue([1, 3])
+    assert Queue([o]) != Queue([o, o])
+    assert Queue([]) != Queue([o])
+    assert not (Queue([o, o]) != Queue([o, o]))
+    assert not (Queue([o]) != Queue([o]))
+    assert not (Queue() != Queue([]))