From 662adfe1585c7eebede9006a76dfd379ff13734c Mon Sep 17 00:00:00 2001
From: Alessandro Candido <candido.ale@gmail.com>
Date: Wed, 15 Feb 2023 16:36:42 +0100
Subject: [PATCH] Drop circuit-specific dedicated handling for swaps

---
 src/qibotn/quimb.py              | 17 +++++++++--------
 tests/config.py                  |  1 -
 tests/test_qasm_quimb_backend.py | 18 +++++++-----------
 3 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/src/qibotn/quimb.py b/src/qibotn/quimb.py
index 46a527c..8414540 100644
--- a/src/qibotn/quimb.py
+++ b/src/qibotn/quimb.py
@@ -3,16 +3,17 @@ import quimb.tensor as qtn
 from qibo.models import Circuit as QiboCircuit
 
 
-def from_qibo(circuit: QiboCircuit, swaps: bool = True, psi0=None):
+def from_qibo(circuit: QiboCircuit, psi0=None):
     nqubits = circuit.nqubits
     tncirc = qtn.Circuit(nqubits, psi0=psi0)
 
     for gate in circuit.queue:
-        tncirc.apply_gate(gate.name)
-
-    if swaps:
-        for i in range(nqubits // 2):  # TODO: Ignore the barrier indices?
-            tncirc.apply_gate("SWAP", i, nqubits - i - 1)
+        tncirc.apply_gate(
+            gate.name,
+            *gate.parameters,
+            *gate.qubits,
+            parametrize=len(gate.parameters) > 0
+        )
 
     return tncirc
 
@@ -23,7 +24,7 @@ def init_state_tn(nqubits, init_state_sv):
     return qtn.tensor_1d.MatrixProductState.from_dense(init_state_sv, dims)
 
 
-def eval(qasm: str, init_state, backend="numpy", swaps=True):
+def eval(qasm: str, init_state, backend="numpy"):
     """Evaluate QASM with Quimb
 
     backend (quimb): numpy, cupy, jax. Passed to ``opt_einsum``.
@@ -31,7 +32,7 @@ def eval(qasm: str, init_state, backend="numpy", swaps=True):
     """
     circuit = QiboCircuit.from_qasm(qasm)
     init_state_mps = init_state_tn(circuit.nqubits, init_state)
-    circ_quimb = from_qibo(circuit, swaps=swaps, psi0=init_state_mps)
+    circ_quimb = from_qibo(circuit, psi0=init_state_mps)
     interim = circ_quimb.psi.full_simplify(seq="DRC")
     amplitudes = interim.to_dense(backend=backend).flatten()
 
diff --git a/tests/config.py b/tests/config.py
index 7570e30..7403673 100644
--- a/tests/config.py
+++ b/tests/config.py
@@ -6,7 +6,6 @@ from typing import Optional
 class Executor:
     backend: str
     platform: Optional[str] = None
-    swaps: bool = True
 
 
 qibo = Executor(backend="qibojit", platform="numpy")
diff --git a/tests/test_qasm_quimb_backend.py b/tests/test_qasm_quimb_backend.py
index db1ad27..e962018 100644
--- a/tests/test_qasm_quimb_backend.py
+++ b/tests/test_qasm_quimb_backend.py
@@ -1,13 +1,12 @@
-import os
-
-import pytest
-import qibo
-from qibo.models import QFT
-import numpy as np
 import copy
+import os
 from timeit import default_timer as timer
 
 import config
+import numpy as np
+import pytest
+import qibo
+from qibo.models import QFT
 
 
 def create_init_state(nqubits):
@@ -44,7 +43,7 @@ def test_eval(nqubits: int):
     # Test qibo
     qibo.set_backend(backend=config.qibo.backend, platform=config.qibo.platform)
     qibo_time, (qibo_circ, result_sv) = time(
-        lambda: qibo_qft(nqubits, init_state, swaps=config.qibo.swaps)
+        lambda: qibo_qft(nqubits, init_state, swaps=True)
     )
 
     # Convert to qasm for other backends
@@ -53,10 +52,7 @@ def test_eval(nqubits: int):
     # Test quimb
     quimb_time, result_tn = time(
         lambda: qibotn.quimb.eval(
-            qasm_circ,
-            init_state_tn,
-            backend=config.quimb.backend,
-            swaps=config.quimb.swaps,
+            qasm_circ, init_state_tn, backend=config.quimb.backend
         )
     )