fix: type errors, Preprocessor connectivity check, utils.py -> assert…

…s.py

src/qibo/models/circuit.py

@@ -165,7 +165,7 @@ class Circuit:
 
     def __init__(
         self,
-        nqubits: Optional[Union[str, list]] = None,
+        nqubits: Optional[Union[int, list]] = None,
         accelerators=None,
         density_matrix: bool = False,
         wire_names: Optional[list] = None,

src/qibo/transpiler/optimizer.py

@@ -1,3 +1,5 @@
+from typing import Optional
+
 import networkx as nx
 
 from qibo import gates
@@ -13,13 +15,11 @@ class Preprocessing(Optimizer):
         connectivity (:class:`networkx.Graph`): hardware chip connectivity.
     """
 
-    def __init__(self, connectivity: nx.Graph = None):
+    def __init__(self, connectivity: Optional[nx.Graph] = None):
         self.connectivity = connectivity
 
     def __call__(self, circuit: Circuit) -> Circuit:
-        if self.connectivity is None or not all(
-            qubit in self.connectivity.nodes for qubit in circuit.wire_names
-        ):
+        if not all(qubit in self.connectivity.nodes for qubit in circuit.wire_names):
             raise_error(
                 ValueError,
                 "The circuit qubits are not in the connectivity graph.",

src/qibo/transpiler/pipeline.py

@@ -8,12 +8,12 @@
     TranspilerPipelineError,
 )
 from qibo.transpiler.abstract import Optimizer, Placer, Router
-from qibo.transpiler.unroller import DecompositionError, NativeGates, Unroller
-from qibo.transpiler.utils import (
+from qibo.transpiler.asserts import (
     assert_connectivity,
     assert_decomposition,
     assert_placement,
 )
+from qibo.transpiler.unroller import DecompositionError, NativeGates, Unroller
 
 
 def restrict_connectivity_qubits(connectivity: nx.Graph, qubits: list[str]):

src/qibo/transpiler/placer.py

@@ -8,8 +8,8 @@
 from qibo.models import Circuit
 from qibo.transpiler._exceptions import PlacementError
 from qibo.transpiler.abstract import Placer, Router
+from qibo.transpiler.asserts import assert_placement
 from qibo.transpiler.router import _find_connected_qubit
-from qibo.transpiler.utils import assert_placement
 
 
 def _find_gates_qubits_pairs(circuit: Circuit):
@@ -48,7 +48,7 @@ class StarConnectivityPlacer(Placer):
         connectivity (:class:`networkx.Graph`): star connectivity graph.
     """
 
-    def __init__(self, connectivity: nx.Graph = None):
+    def __init__(self, connectivity: Optional[nx.Graph] = None):
         self.connectivity = connectivity
         self.middle_qubit = None
 
@@ -114,7 +114,7 @@ class Subgraph(Placer):
         connectivity (:class:`networkx.Graph`): chip connectivity.
     """
 
-    def __init__(self, connectivity: nx.Graph = None):
+    def __init__(self, connectivity: Optional[nx.Graph] = None):
         self.connectivity = connectivity
 
     def __call__(self, circuit: Circuit):
@@ -172,7 +172,9 @@ class Random(Placer):
             initializes a generator with a random seed. Defaults to ``None``.
     """
 
-    def __init__(self, connectivity: nx.Graph = None, samples: int = 100, seed=None):
+    def __init__(
+        self, connectivity: Optional[nx.Graph] = None, samples: int = 100, seed=None
+    ):
         self.connectivity = connectivity
         self.samples = samples
         self.seed = seed
@@ -256,7 +258,7 @@ class ReverseTraversal(Placer):
     def __init__(
         self,
         routing_algorithm: Router,
-        connectivity: nx.Graph = None,
+        connectivity: Optional[nx.Graph] = None,
         depth: Optional[int] = None,
     ):
         self.connectivity = connectivity

src/qibo/transpiler/router.py

@@ -10,8 +10,8 @@
 from qibo.models import Circuit
 from qibo.transpiler._exceptions import ConnectivityError
 from qibo.transpiler.abstract import Router
+from qibo.transpiler.asserts import assert_placement
 from qibo.transpiler.blocks import Block, CircuitBlocks
-from qibo.transpiler.utils import assert_placement
 
 
 class StarConnectivityRouter(Router):
@@ -31,7 +31,7 @@ class StarConnectivityRouter(Router):
         connectivity (:class:`networkx.Graph`): star connectivity graph.
     """
 
-    def __init__(self, connectivity: nx.Graph):
+    def __init__(self, connectivity: Optional[nx.Graph] = None):
         self.connectivity = connectivity
         self.middle_qubit = None
 
@@ -314,7 +314,9 @@ class ShortestPaths(Router):
             If ``None``, defaults to :math:`42`. Defaults to ``None``.
     """
 
-    def __init__(self, connectivity: nx.Graph = None, seed: Optional[int] = None):
+    def __init__(
+        self, connectivity: Optional[nx.Graph] = None, seed: Optional[int] = None
+    ):
         self.connectivity = connectivity
         self._front_layer = None
         self.circuit_map = None
@@ -601,7 +603,7 @@ class Sabre(Router):
 
     def __init__(
         self,
-        connectivity: nx.Graph = None,
+        connectivity: Optional[nx.Graph] = None,
         lookahead: int = 2,
         decay_lookahead: float = 0.6,
         delta: float = 0.001,

tests/test_transpiler_utils.py → tests/test_transpiler_asserts.py

@@ -8,14 +8,14 @@
     PlacementError,
     TranspilerPipelineError,
 )
-from qibo.transpiler.pipeline import restrict_connectivity_qubits
-from qibo.transpiler.unroller import NativeGates
-from qibo.transpiler.utils import (
+from qibo.transpiler.asserts import (
     assert_circuit_equivalence,
     assert_connectivity,
     assert_decomposition,
     assert_placement,
 )
+from qibo.transpiler.pipeline import restrict_connectivity_qubits
+from qibo.transpiler.unroller import NativeGates
 
 
 def test_assert_circuit_equivalence_equal():

tests/test_transpiler_decompositions.py

@@ -5,8 +5,8 @@
 from qibo.backends import NumpyBackend
 from qibo.models import Circuit
 from qibo.quantum_info.random_ensembles import random_unitary
+from qibo.transpiler.asserts import assert_decomposition
 from qibo.transpiler.unroller import NativeGates, translate_gate
-from qibo.transpiler.utils import assert_decomposition
 
 default_natives = NativeGates.Z | NativeGates.RZ | NativeGates.M | NativeGates.I
 

tests/test_transpiler_optimizer.py

@@ -8,11 +8,6 @@
 
 def test_preprocessing_error(star_connectivity):
     circ = Circuit(7)
-
-    preprocesser = Preprocessing()
-    with pytest.raises(ValueError):
-        new_circuit = preprocesser(circuit=circ)
-
     preprocesser = Preprocessing(connectivity=star_connectivity())
     with pytest.raises(ValueError):
         new_circuit = preprocesser(circuit=circ)

tests/test_transpiler_pipeline.py

@@ -5,12 +5,12 @@
 from qibo import gates
 from qibo.models import Circuit
 from qibo.transpiler._exceptions import ConnectivityError, TranspilerPipelineError
+from qibo.transpiler.asserts import assert_circuit_equivalence, assert_transpiling
 from qibo.transpiler.optimizer import Preprocessing
 from qibo.transpiler.pipeline import Passes, restrict_connectivity_qubits
 from qibo.transpiler.placer import Random, ReverseTraversal
 from qibo.transpiler.router import Sabre, ShortestPaths
 from qibo.transpiler.unroller import NativeGates, Unroller
-from qibo.transpiler.utils import assert_circuit_equivalence, assert_transpiling
 
 
 def generate_random_circuit(nqubits, ngates, names=None, seed=42):

tests/test_transpiler_placer.py

@@ -4,6 +4,7 @@
 from qibo import gates
 from qibo.models import Circuit
 from qibo.transpiler._exceptions import PlacementError, TranspilerPipelineError
+from qibo.transpiler.asserts import assert_placement
 from qibo.transpiler.pipeline import restrict_connectivity_qubits
 from qibo.transpiler.placer import (
     Random,
@@ -13,7 +14,6 @@
     _find_gates_qubits_pairs,
 )
 from qibo.transpiler.router import ShortestPaths
-from qibo.transpiler.utils import assert_placement
 
 
 def star_circuit(names=[0, 1, 2, 3, 4]):

tests/test_transpiler_router.py

@@ -9,6 +9,12 @@
 from qibo.models import Circuit
 from qibo.quantum_info.random_ensembles import random_unitary
 from qibo.transpiler._exceptions import ConnectivityError
+from qibo.transpiler.asserts import (
+    _transpose_qubits,
+    assert_circuit_equivalence,
+    assert_connectivity,
+    assert_placement,
+)
 from qibo.transpiler.pipeline import restrict_connectivity_qubits
 from qibo.transpiler.placer import Random, StarConnectivityPlacer, Subgraph
 from qibo.transpiler.router import (
@@ -17,12 +23,6 @@
     ShortestPaths,
     StarConnectivityRouter,
 )
-from qibo.transpiler.utils import (
-    _transpose_qubits,
-    assert_circuit_equivalence,
-    assert_connectivity,
-    assert_placement,
-)
 
 
 def line_connectivity(n, names=None):

tests/test_transpiler_unroller.py

@@ -3,8 +3,8 @@
 from qibo import gates
 from qibo.models import Circuit
 from qibo.transpiler._exceptions import DecompositionError
+from qibo.transpiler.asserts import assert_decomposition
 from qibo.transpiler.unroller import NativeGates, Unroller, translate_gate
-from qibo.transpiler.utils import assert_decomposition
 
 
 def test_native_gates_from_gatelist():