From 99908e6d3e6a642445f8b6b4a8e7ceebf3dabf64 Mon Sep 17 00:00:00 2001
From: Connor Troy <connor.troy@tuta.io>
Date: Mon, 6 Sep 2021 00:14:26 -0600
Subject: [PATCH] Add deque imul method

---
 vm/src/stdlib/collections.rs | 39 +++++++++++++++++++++++++++++++-----
 1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/vm/src/stdlib/collections.rs b/vm/src/stdlib/collections.rs
index a4446ed2c..e9b4b0c37 100644
--- a/vm/src/stdlib/collections.rs
+++ b/vm/src/stdlib/collections.rs
@@ -59,9 +59,9 @@ mod _collections {
         }
     }
 
-    struct SimpleSeqDeque<'a>(PyRwLockReadGuard<'a, VecDeque<PyObjectRef>>);
+    struct SimpleSeqDeque(VecDeque<PyObjectRef>);
 
-    impl sequence::SimpleSeq for SimpleSeqDeque<'_> {
+    impl sequence::SimpleSeq for SimpleSeqDeque {
         fn len(&self) -> usize {
             self.0.len()
         }
@@ -71,9 +71,21 @@ mod _collections {
         }
     }
 
-    impl<'a> From<PyRwLockReadGuard<'a, VecDeque<PyObjectRef>>> for SimpleSeqDeque<'a> {
-        fn from(from: PyRwLockReadGuard<'a, VecDeque<PyObjectRef>>) -> Self {
-            Self(from)
+    impl From<VecDeque<PyObjectRef>> for SimpleSeqDeque {
+        fn from(deque: VecDeque<PyObjectRef>) -> Self {
+            Self(deque)
+        }
+    }
+
+    impl From<PyRwLockReadGuard<'_, VecDeque<PyObjectRef>>> for SimpleSeqDeque {
+        fn from(deque: PyRwLockReadGuard<'_, VecDeque<PyObjectRef>>) -> Self {
+            Self(deque.clone())
+        }
+    }
+
+    impl From<PyRwLockWriteGuard<'_, VecDeque<PyObjectRef>>> for SimpleSeqDeque {
+        fn from(deque: PyRwLockWriteGuard<'_, VecDeque<PyObjectRef>>) -> Self {
+            Self(deque.clone())
         }
     }
 
@@ -471,6 +483,23 @@ mod _collections {
             })
         }
 
+        #[pymethod(magic)]
+        fn imul(zelf: PyRef<Self>, value: isize, vm: &VirtualMachine) -> PyResult<PyRef<Self>> {
+            let mut deque = zelf.borrow_deque_mut();
+            let seq: SimpleSeqDeque = deque.clone().into();
+            let mul = sequence::seq_mul(vm, &seq, value)?;
+
+            let skipped = zelf
+                .maxlen
+                .and_then(|maxlen| mul.len().checked_sub(maxlen))
+                .unwrap_or(0);
+
+            let mut new_deque: VecDeque<PyObjectRef> = mul.skip(skipped).cloned().collect();
+            std::mem::swap(&mut *deque, &mut new_deque);
+            drop(deque);
+            Ok(zelf)
+        }
+
         #[pymethod(magic)]
         fn len(&self) -> usize {
             self.borrow_deque().len()