From ebac9f5457c8ac4e644964c395e691db37fe9957 Mon Sep 17 00:00:00 2001
From: Adam Reichold <adam.reichold@t-online.de>
Date: Tue, 13 Sep 2022 22:05:12 +0200
Subject: [PATCH] Further relax extract_sequence as neither PyObject::len nor
 PyObject::iter actually need the sequence protocol.

---
 src/types/sequence.rs | 15 +++------------
 1 file changed, 3 insertions(+), 12 deletions(-)

diff --git a/src/types/sequence.rs b/src/types/sequence.rs
index af7cd0c5d19..9621b32d940 100644
--- a/src/types/sequence.rs
+++ b/src/types/sequence.rs
@@ -299,18 +299,9 @@ fn extract_sequence<'s, T>(obj: &'s PyAny) -> PyResult<Vec<T>>
 where
     T: FromPyObject<'s>,
 {
-    // Types that pass `PySequence_Check` usually implement enough of the sequence protocol
-    // to support this function and if not, we will only fail extraction safely.
-    let seq = unsafe {
-        if ffi::PySequence_Check(obj.as_ptr()) != 0 {
-            <PySequence as PyTryFrom>::try_from_unchecked(obj)
-        } else {
-            return Err(PyDowncastError::new(obj, "Sequence").into());
-        }
-    };
-
-    let mut v = Vec::with_capacity(seq.len().unwrap_or(0) as usize);
-    for item in seq.iter()? {
+    let iter = obj.iter()?;
+    let mut v = Vec::with_capacity(obj.len().unwrap_or(0) as usize);
+    for item in iter {
         v.push(item?.extract::<T>()?);
     }
     Ok(v)