2 files changed, 38 insertions, 2 deletions

diff --git a/src/lib.rs b/src/lib.rs
index bbaa08c..588f4e9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -17,6 +17,7 @@ use adblock::engine::Engine as RustEngine;
 use pyo3::class::PyObjectProtocol;
 use pyo3::exceptions::ValueError as PyValueError;
 use pyo3::prelude::*;
+use pyo3::types::PyBytes;
 use pyo3::PyErr;
 
 use std::collections::HashMap;
@@ -348,7 +349,13 @@ impl Engine {
     /// Serialize this blocking engine to bytes. They can then be deserialized
     /// using `deserialize()` to get the same engine again.
     #[text_signature = "($self)"]
-    pub fn serialize(&mut self) -> PyResult<Vec<u8>> {
+    pub fn serialize<'p>(&mut self, py: Python<'p>) -> PyResult<&'p PyBytes> {
+        let bytes = self.serialize_inner()?;
+        let py_bytes = PyBytes::new(py, &bytes);
+        Ok(py_bytes)
+    }
+
+    fn serialize_inner(&mut self) -> PyResult<Vec<u8>> {
         let result = self.engine.serialize();
         match result {
             Ok(x) => Ok(x),
@@ -364,7 +371,7 @@ impl Engine {
     /// again.
     #[text_signature = "($self, file)"]
     pub fn serialize_to_file(&mut self, file: &str) -> PyResult<()> {
-        let data = self.serialize()?;
+        let data = self.serialize_inner()?;
         let mut fd = fs::OpenOptions::new()
             .create(true)
             .truncate(true)
diff --git a/tests/test_engine.py b/tests/test_engine.py
index af15b6d..28e25e6 100644
--- a/tests/test_engine.py
+++ b/tests/test_engine.py
@@ -1,4 +1,5 @@
 import adblock
+import pytest
 
 
 def test_engine_arguments():
@@ -9,3 +10,31 @@ def test_engine_arguments():
     adblock.Engine(network_filters=[])
     adblock.Engine(load_network=False, load_cosmetic=True, debug=False)
     adblock.Engine(debug=True)
+
+
+def test_serde_file(tmpdir):
+    path = str(tmpdir / "cache.dat")
+
+    engine0 = adblock.Engine()
+    with pytest.raises(FileNotFoundError):
+        # We haven't created the cache.dat file, so we should get an exception
+        # when attempting to deserialize.
+        engine0.deserialize_from_file(path)
+
+    engine1 = adblock.Engine()
+    serialization_result = engine1.serialize_to_file(path)
+    assert serialization_result is None
+
+    engine2 = adblock.Engine()
+    deserialization_result = engine2.deserialize_from_file(path)
+    assert deserialization_result is None
+
+
+def test_serde():
+    engine = adblock.Engine()
+    serialization_result = engine.serialize()
+    assert isinstance(serialization_result, bytes)
+
+    engine2 = adblock.Engine()
+    deserialization_result = engine2.deserialize(serialization_result)
+    assert deserialization_result is None