fix: implemented change recommended in review + added custom bloq for testing

Author: Axel-pappalardo

qualtran/quirk_interop/bloq_to_quirk.py

@@ -31,7 +31,7 @@ def __init__(self, cbloq: CompositeBloq, max_n_lines: int = 100):
         self._join_to_split_id = self._build_join_to_split_map()
         self._split_to_join_id = self._build_split_to_join_map()
 
-    def _find_dual_on_line(self, line: int, start: int, dual_cls):
+    def _find_dual_on_line(self, line: int, start: int, dual_cls: Bloq):
         dual_candidates = [
             (rpos.seq_x, soq.binst.i)  # type: ignore[union-attr]
             for soq, rpos in self.soq_assign.items()
@@ -102,19 +102,11 @@ def composite_bloq_to_quirk(
     circuit = [col for col in sparse_circuit if col != empty_col]
     if circuit == []:
         raise ValueError(f"{cbloq} is an empty circuit")
-    nb_deleted_lines = 0
-    for i in range(
-        msd.max_y + 1
-    ):  # deleting lines of the circuit which are not used (happens with partition)
-        ind = i - nb_deleted_lines
-        for col in circuit:
-            line_is_useless = col[ind] == '1'
-            if not line_is_useless:
-                break
-        if line_is_useless:
-            for col in circuit:
-                col.pop(ind)
-            nb_deleted_lines += 1
+    # deleting lines of the circuit which are not used (happens with partition)
+    if circuit:
+        num_lines = len(circuit[0])
+        lines_to_keep = [i for i in range(num_lines) if any(col[i] != '1' for col in circuit)]
+        circuit = [[col[i] for i in lines_to_keep] for col in circuit]
 
     quirk_url = "https://algassert.com/quirk"
     start = '#circuit={"cols":['

qualtran/quirk_interop/bloq_to_quirk_test.py

@@ -1,10 +1,8 @@
 import pytest
 
-from qualtran import BloqBuilder, QAny, QUInt
+from qualtran import BloqBuilder, QAny
+from qualtran.bloqs.basic_gates import Toffoli, XGate
 from qualtran.bloqs.bookkeeping import Allocate, Join, Split
-from qualtran.bloqs.basic_gates import Toffoli
-from qualtran.bloqs.mcmt import MultiTargetCNOT
-from qualtran.bloqs.arithmetic import Add, Negate
 from qualtran.quirk_interop.bloq_to_quirk import (
     SparseLineManager,
     bloq_to_quirk,
@@ -14,12 +12,21 @@
 
 def _build_split_join_split_cbloq(n):
     bb = BloqBuilder()
-    q = bb.add(Allocate(QAny(n)))
-    qs = bb.add(Split(QAny(n)), reg=q)
-    q_joined = bb.add(Join(QAny(n)), reg=qs)
-    qs_again = bb.add(Split(QAny(n)), reg=q_joined)
-    out = bb.add(Join(QAny(n)), reg=qs_again)
-    return bb.finalize(out=out)
+    q1 = bb.add(Allocate(QAny(n)))
+    q2 = bb.add(Allocate(QAny(n)))
+    qs1 = bb.add(Split(QAny(n)), reg=q1)
+    qs2 = bb.add(Split(QAny(n)), reg=q2)
+    for i in range(n):
+        qs1[i] = bb.add(XGate(), q=qs1[i])
+    q1 = bb.add(Join(QAny(n)), reg=qs1)
+    q2 = bb.add(Join(QAny(n)), reg=qs2)
+    qs1 = bb.add(Split(QAny(n)), reg=q1)
+    qs2 = bb.add(Split(QAny(n)), reg=q2)
+    for i in range(n):
+        qs2[i] = bb.add(XGate(), q=qs2[i])
+    q2 = bb.add(Join(QAny(n)), reg=qs2)
+    q1 = bb.add(Join(QAny(n)), reg=qs1)
+    return bb.finalize(q1=q1, q2=q2)
 
 
 @pytest.mark.parametrize("n", range(3, 6))
@@ -33,29 +40,22 @@ def test_sparse_line_manager_builds_dual_maps(n):
 
 @pytest.mark.parametrize("n", range(3, 6))
 def test_composite_bloq_to_quirk_url_shape(n):
-    cbloq = MultiTargetCNOT(n).decompose_bloq().flatten()
+    cbloq = _build_split_join_split_cbloq(n)
     url = composite_bloq_to_quirk(cbloq)
 
     assert url.startswith('https://algassert.com/quirk#circuit={"cols":[')
     assert url.endswith(']}')
 
 
-def test_bloq_to_quirk():
-    url_add = bloq_to_quirk(Add(QUInt(5)))
-    assert url_add.startswith('https://algassert.com/quirk#circuit={"cols":[')
-    assert url_add.endswith(']}')
-    url_mtcnot = bloq_to_quirk(MultiTargetCNOT(3))
-    assert (
-        url_mtcnot
-        == 'https://algassert.com/quirk#circuit={"cols":[[1,"•",1,"X"],[1,"•","X",1],["•","X",1,1],[1,"•","X",1],[1,"•",1,"X"]]}'
-    )
-
-
-def test_negate_to_quirk():
-    url = bloq_to_quirk(Negate(QUInt(2)))
+def test_composite_bloq_to_quirk():
+    cbloq1 = _build_split_join_split_cbloq(1)
+    url1 = composite_bloq_to_quirk(cbloq1)
+    assert url1 == 'https://algassert.com/quirk#circuit={"cols":[["X",1],[1,"X"]]}'
+    cbloq2 = _build_split_join_split_cbloq(2)
+    url2 = composite_bloq_to_quirk(cbloq2)
     assert (
-        url
-        == 'https://algassert.com/quirk#circuit={"cols":[["X",1,1,1,1],[1,"X",1,1,1],[1,1,1,"X",1],[1,"•",1,"•","X"],["X",1,1,1,"•"],[1,"•",1,"•","X"],["X",1,"•",1,1],[1,"X",1,"•",1],[1,1,1,"X",1]]}'
+        url2
+        == 'https://algassert.com/quirk#circuit={"cols":[["X",1,1,1],[1,"X",1,1],[1,1,"X",1],[1,1,1,"X"]]}'
     )