add benchmark for isinstance chain

Cargo.toml

@@ -114,6 +114,10 @@ full = [
     "rust_decimal",
 ]
 
+[[bench]]
+name = "bench_any"
+harness = false
+
 [[bench]]
 name = "bench_call"
 harness = false

benches/bench_any.rs

@@ -0,0 +1,80 @@
+use criterion::{criterion_group, criterion_main, Bencher, Criterion};
+
+use pyo3::{
+    types::{
+        PyBool, PyByteArray, PyBytes, PyDict, PyFloat, PyFrozenSet, PyInt, PyList, PyMapping,
+        PySequence, PySet, PyString, PyTuple,
+    },
+    PyAny, PyResult, Python,
+};
+
+#[derive(PartialEq, Eq, Debug)]
+enum ObjectType {
+    None,
+    Bool,
+    ByteArray,
+    Bytes,
+    Dict,
+    Float,
+    FrozenSet,
+    Int,
+    List,
+    Set,
+    Str,
+    Tuple,
+    Sequence,
+    Mapping,
+    Unknown,
+}
+
+fn find_object_type(obj: &PyAny) -> PyResult<ObjectType> {
+    let obj_type = if obj.is_none() {
+        ObjectType::None
+    } else if obj.is_instance_of::<PyBool>()? {
+        ObjectType::Bool
+    } else if obj.is_instance_of::<PyByteArray>()? {
+        ObjectType::ByteArray
+    } else if obj.is_instance_of::<PyBytes>()? {
+        ObjectType::Bytes
+    } else if obj.is_instance_of::<PyDict>()? {
+        ObjectType::Dict
+    } else if obj.is_instance_of::<PyFloat>()? {
+        ObjectType::Float
+    } else if obj.is_instance_of::<PyFrozenSet>()? {
+        ObjectType::FrozenSet
+    } else if obj.is_instance_of::<PyInt>()? {
+        ObjectType::Int
+    } else if obj.is_instance_of::<PyList>()? {
+        ObjectType::List
+    } else if obj.is_instance_of::<PySet>()? {
+        ObjectType::Set
+    } else if obj.is_instance_of::<PyString>()? {
+        ObjectType::Str
+    } else if obj.is_instance_of::<PyTuple>()? {
+        ObjectType::Tuple
+    } else if obj.downcast::<PySequence>().is_ok() {
+        ObjectType::Sequence
+    } else if obj.downcast::<PyMapping>().is_ok() {
+        ObjectType::Mapping
+    } else {
+        ObjectType::Unknown
+    };
+    Ok(obj_type)
+}
+
+fn bench_identify_object_type(b: &mut Bencher<'_>) {
+    Python::with_gil(|py| {
+        let obj = py.eval("object()", None, None).unwrap();
+
+        b.iter(|| find_object_type(obj).unwrap());
+
+        assert_eq!(find_object_type(obj).unwrap(), ObjectType::Unknown);
+    });
+}
+
+fn criterion_benchmark(c: &mut Criterion) {
+    c.bench_function("identify_object_type", bench_identify_object_type);
+}
+
+criterion_group!(benches, criterion_benchmark);
+criterion_main!(benches);