Remove: Default initialization methods from custom datatypes.

- Use `__getnewargs__ instead.

crates/circuit/src/equivalence.rs

@@ -17,7 +17,7 @@ use rustworkx_core::petgraph::csr::IndexType;
 use rustworkx_core::petgraph::stable_graph::StableDiGraph;
 use rustworkx_core::petgraph::visit::IntoEdgeReferences;
 
-use smallvec::{smallvec, SmallVec};
+use smallvec::SmallVec;
 use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};
 use std::{error::Error, fmt::Display};
@@ -42,7 +42,8 @@ mod exceptions {
     import_exception_bound! {qiskit.circuit.exceptions, CircuitError}
 }
 pub static PYDIGRAPH: ImportOnceCell = ImportOnceCell::new("rustworkx", "PyDiGraph");
-pub static QUANTUMCIRCUIT: ImportOnceCell = ImportOnceCell::new("qiskit.circuit", "QuantumCircuit");
+pub static QUANTUMCIRCUIT: ImportOnceCell =
+    ImportOnceCell::new("qiskit.circuit.quantumcircuit", "QuantumCircuit");
 
 // Custom Structs
 
@@ -58,7 +59,7 @@ pub struct Key {
 #[pymethods]
 impl Key {
     #[new]
-    #[pyo3(signature = (name="".to_string(), num_qubits=0))]
+    #[pyo3(signature = (name, num_qubits))]
     fn new(name: String, num_qubits: u32) -> Self {
         Self { name, num_qubits }
     }
@@ -81,6 +82,10 @@ impl Key {
         (slf.name.clone(), slf.num_qubits)
     }
 
+    fn __getnewargs__(slf: PyRef<Self>) -> (String, u32) {
+        Key::__getstate__(slf)
+    }
+
     fn __setstate__(mut slf: PyRefMut<Self>, state: (String, u32)) {
         slf.name = state.0;
         slf.num_qubits = state.1;
@@ -97,17 +102,8 @@ impl Display for Key {
     }
 }
 
-impl Default for Key {
-    fn default() -> Self {
-        Self {
-            name: "".to_string(),
-            num_qubits: 0,
-        }
-    }
-}
-
 #[pyclass(sequence, module = "qiskit._accelerate.circuit.equivalence")]
-#[derive(Debug, Clone, PartialEq, Default)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct Equivalence {
     #[pyo3(get)]
     pub params: SmallVec<[Param; 3]>,
@@ -118,7 +114,7 @@ pub struct Equivalence {
 #[pymethods]
 impl Equivalence {
     #[new]
-    #[pyo3(signature = (params=smallvec![], circuit=CircuitRep::default()))]
+    #[pyo3(signature = (params, circuit))]
     fn new(params: SmallVec<[Param; 3]>, circuit: CircuitRep) -> Self {
         Self { circuit, params }
     }
@@ -131,8 +127,12 @@ impl Equivalence {
         self.eq(&other)
     }
 
-    fn __getstate__(slf: PyRef<Self>) -> (SmallVec<[Param; 3]>, CircuitRep) {
-        (slf.params.clone(), slf.circuit.clone())
+    fn __getstate__(&self, py: Python) -> (PyObject, PyObject) {
+        (self.params.to_object(py), self.circuit.object.clone_ref(py))
+    }
+
+    fn __getnewargs__(&self, py: Python) -> (PyObject, PyObject) {
+        self.__getstate__(py)
     }
 
     fn __setstate__(mut slf: PyRefMut<Self>, state: (SmallVec<[Param; 3]>, CircuitRep)) {
@@ -153,7 +153,7 @@ impl Display for Equivalence {
 }
 
 #[pyclass(sequence, module = "qiskit._accelerate.circuit.equivalence")]
-#[derive(Debug, Clone, PartialEq, Default)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct NodeData {
     #[pyo3(get)]
     key: Key,
@@ -164,7 +164,7 @@ pub struct NodeData {
 #[pymethods]
 impl NodeData {
     #[new]
-    #[pyo3(signature = (key=Key::default(), equivs=vec![]))]
+    #[pyo3(signature = (key, equivs))]
     fn new(key: Key, equivs: Vec<Equivalence>) -> Self {
         Self { key, equivs }
     }
@@ -177,8 +177,12 @@ impl NodeData {
         self.eq(&other)
     }
 
-    fn __getstate__(slf: PyRef<Self>) -> (Key, Vec<Equivalence>) {
-        (slf.key.clone(), slf.equivs.clone())
+    fn __getstate__(&self) -> (Key, Vec<Equivalence>) {
+        (self.key.clone(), self.equivs.clone())
+    }
+
+    fn __getnewargs__(&self) -> (Key, Vec<Equivalence>) {
+        self.__getstate__()
     }
 
     fn __setstate__(mut slf: PyRefMut<Self>, state: (Key, Vec<Equivalence>)) {
@@ -199,7 +203,7 @@ impl Display for NodeData {
 }
 
 #[pyclass(sequence, module = "qiskit._accelerate.circuit.equivalence")]
-#[derive(Debug, Clone, PartialEq, Default)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct EdgeData {
     #[pyo3(get)]
     pub index: usize,
@@ -214,7 +218,7 @@ pub struct EdgeData {
 #[pymethods]
 impl EdgeData {
     #[new]
-    #[pyo3(signature = (index=0, num_gates=0, rule=Equivalence::default(), source=Key::default()))]
+    #[pyo3(signature = (index, num_gates, rule, source))]
     fn new(index: usize, num_gates: usize, rule: Equivalence, source: Key) -> Self {
         Self {
             index,
@@ -241,6 +245,15 @@ impl EdgeData {
         )
     }
 
+    fn __getnewargs__(slf: PyRef<Self>) -> (usize, usize, Equivalence, Key) {
+        (
+            slf.index,
+            slf.num_gates,
+            slf.rule.clone(),
+            slf.source.clone(),
+        )
+    }
+
     fn __setstate__(mut slf: PyRefMut<Self>, state: (usize, usize, Equivalence, Key)) {
         slf.index = state.0;
         slf.num_gates = state.1;
@@ -366,18 +379,6 @@ impl IntoPy<PyObject> for CircuitRep {
     }
 }
 
-impl Default for CircuitRep {
-    fn default() -> Self {
-        Self {
-            object: Python::with_gil(|py| py.None()),
-            num_qubits: 0,
-            num_clbits: 0,
-            params: None,
-            data: None,
-        }
-    }
-}
-
 // Custom Types
 type GraphType = StableDiGraph<NodeData, EdgeData>;
 type KTIType = HashMap<Key, NodeIndex>;