Add dropwhile.__reduce__

Author: dvermd

extra_tests/snippets/stdlib_itertools.py

@@ -2,6 +2,7 @@
 
 from testutils import assert_raises
 
+import pickle
 
 # itertools.chain tests
 chain = itertools.chain
@@ -279,6 +280,17 @@ def assert_matches_seq(it, seq):
 with assert_raises(StopIteration):
     next(it)
 
+def underten(x):
+    return x<10
+
+it = itertools.dropwhile(underten, [1, 3, 5, 20, 2, 4, 6, 8])
+assert pickle.dumps(it, 0) == b'citertools\ndropwhile\np0\n(c__main__\nunderten\np1\nc__builtin__\niter\np2\n((lp3\nI1\naI3\naI5\naI20\naI2\naI4\naI6\naI8\natp4\nRp5\nI0\nbtp6\nRp7\nI0\nb.'
+assert pickle.dumps(it, 1) == b'citertools\ndropwhile\nq\x00(c__main__\nunderten\nq\x01c__builtin__\niter\nq\x02(]q\x03(K\x01K\x03K\x05K\x14K\x02K\x04K\x06K\x08etq\x04Rq\x05K\x00btq\x06Rq\x07K\x00b.'
+assert pickle.dumps(it, 2) == b'\x80\x02citertools\ndropwhile\nq\x00c__main__\nunderten\nq\x01c__builtin__\niter\nq\x02]q\x03(K\x01K\x03K\x05K\x14K\x02K\x04K\x06K\x08e\x85q\x04Rq\x05K\x00b\x86q\x06Rq\x07K\x00b.'
+assert pickle.dumps(it, 3) == b'\x80\x03citertools\ndropwhile\nq\x00c__main__\nunderten\nq\x01cbuiltins\niter\nq\x02]q\x03(K\x01K\x03K\x05K\x14K\x02K\x04K\x06K\x08e\x85q\x04Rq\x05K\x00b\x86q\x06Rq\x07K\x00b.'
+assert pickle.dumps(it, 4) == b'\x80\x04\x95i\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x94\x8c\tdropwhile\x94\x93\x94\x8c\x08__main__\x94\x8c\x08underten\x94\x93\x94\x8c\x08builtins\x94\x8c\x04iter\x94\x93\x94]\x94(K\x01K\x03K\x05K\x14K\x02K\x04K\x06K\x08e\x85\x94R\x94K\x00b\x86\x94R\x94K\x00b.'
+assert pickle.dumps(it, 5) == b'\x80\x05\x95i\x00\x00\x00\x00\x00\x00\x00\x8c\titertools\x94\x8c\tdropwhile\x94\x93\x94\x8c\x08__main__\x94\x8c\x08underten\x94\x93\x94\x8c\x08builtins\x94\x8c\x04iter\x94\x93\x94]\x94(K\x01K\x03K\x05K\x14K\x02K\x04K\x06K\x08e\x85\x94R\x94K\x00b\x86\x94R\x94K\x00b.'
+
 
 # itertools.accumulate
 it = itertools.accumulate([6, 3, 7, 1, 0, 9, 8, 8])

vm/src/stdlib/itertools.rs

@@ -2,21 +2,23 @@ pub(crate) use decl::make_module;
 
 #[pymodule(name = "itertools")]
 mod decl {
-    use crate::common::{
-        lock::{PyMutex, PyRwLock, PyRwLockWriteGuard},
-        rc::PyRc,
-    };
     use crate::{
         builtins::{int, PyGenericAlias, PyInt, PyIntRef, PyList, PyTuple, PyTupleRef, PyTypeRef},
+        common::{
+            lock::{PyMutex, PyRwLock, PyRwLockWriteGuard},
+            rc::PyRc,
+        },
         convert::ToPyObject,
-        function::{ArgCallable, FuncArgs, OptionalArg, OptionalOption, PosArgs},
+        function::{ArgCallable, ArgIntoBool, FuncArgs, OptionalArg, OptionalOption, PosArgs},
         identifier,
         protocol::{PyIter, PyIterReturn, PyNumber},
         stdlib::sys,
         types::{Constructor, IterNext, IterNextIterable},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, PyWeakRef, VirtualMachine,
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, PyWeakRef, TryFromObject,
+        VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
+    use num_bigint::BigInt;
     use num_traits::{Signed, ToPrimitive};
     use std::fmt;
 
@@ -540,7 +542,23 @@ mod decl {
     }
 
     #[pyclass(with(IterNext, Constructor), flags(BASETYPE))]
-    impl PyItertoolsDropwhile {}
+    impl PyItertoolsDropwhile {
+        #[pymethod(magic)]
+        fn reduce(zelf: PyRef<Self>) -> (PyTypeRef, (PyObjectRef, PyIter), BigInt) {
+            (
+                zelf.class().clone(),
+                (zelf.predicate.clone().into(), zelf.iterable.clone()),
+                (if zelf.start_flag.load() { 1 } else { 0 }).into(),
+            )
+        }
+        #[pymethod(magic)]
+        fn setstate(zelf: PyRef<Self>, state: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
+            if let Ok(obj) = ArgIntoBool::try_from_object(vm, state) {
+                zelf.start_flag.store(*obj);
+            }
+            Ok(())
+        }
+    }
     impl IterNextIterable for PyItertoolsDropwhile {}
     impl IterNext for PyItertoolsDropwhile {
         fn next(zelf: &Py<Self>, vm: &VirtualMachine) -> PyResult<PyIterReturn> {