Fix pass-manager drawing tests for pydot 3.0 (#12775)

* Fix pass-manager drawing tests for pydot 3.0

Two changes in pydot 3 changed the reference output:

1. previously, attributes were sorted before being output.  Pydot 3
   stores them in declaration order.  Here, we sort our attributes to
   maintain the closest behaviour between the two versions.

2. Text fields (like `label`) that contain special characters now have
   their values enclosed in quote marks.  This is a difference between
   the two versions, and we update the reference files to the new
   version since that's what we'll be using in CI.

Qiskit is still compatible with pydot 2 in general usage, it's just our
tests that are a little more tied to the current version.

* Add test-only constraint on pydot

constraints.txt

@@ -13,3 +13,9 @@ scipy==1.13.1; python_version=='3.12'
 # `macos_11_7` platform tag.  This should be purely a CI artefact, and not
 # affect local usage.
 z3-solver==4.12.2.0; platform_system=="Darwin"
+
+# There are minor differences in output between pydot 2 and pydot 3 for
+# things like the pass-manager drawer.  This is totally fine for general
+# usage, but our test suite uses an exact reference file that uses the
+# pydot 3 output, so we need to enforce that during tests.
+pydot>=3.0.0

qiskit/visualization/pass_manager_visualization.py

@@ -176,7 +176,7 @@ def staged_pass_manager_drawer(pass_manager, filename=None, style=None, raw=Fals
         stage = getattr(pass_manager, st)
 
         if stage is not None:
-            stagegraph = pydot.Cluster(str(st), label=str(st), fontname="helvetica", labeljust="l")
+            stagegraph = pydot.Cluster(str(st), fontname="helvetica", label=str(st), labeljust="l")
             for controller_group in stage.to_flow_controller().tasks:
                 subgraph, component_id, prev_node = draw_subgraph(
                     controller_group, component_id, style, prev_node, idx
@@ -201,7 +201,7 @@ def draw_subgraph(controller_group, component_id, style, prev_node, idx):
         label += f"{controller_group.__class__.__name__}"
 
     # create the subgraph for this controller
-    subgraph = pydot.Cluster(str(component_id), label=label, fontname="helvetica", labeljust="l")
+    subgraph = pydot.Cluster(str(component_id), fontname="helvetica", label=label, labeljust="l")
     component_id += 1
 
     if isinstance(controller_group, BaseController):
@@ -233,19 +233,19 @@ def draw_subgraph(controller_group, component_id, style, prev_node, idx):
             # TODO recursively inject subgraph into subgraph
             node = pydot.Node(
                 str(component_id),
-                label="Nested flow controller",
                 color="k",
-                shape="rectangle",
                 fontname="helvetica",
+                label="Nested flow controller",
+                shape="rectangle",
             )
         else:
             # label is the name of the pass
             node = pydot.Node(
                 str(component_id),
-                label=str(type(task).__name__),
                 color=_get_node_color(task, style),
-                shape="rectangle",
                 fontname="helvetica",
+                label=str(type(task).__name__),
+                shape="rectangle",
             )
 
         subgraph.add_node(node)
@@ -268,12 +268,12 @@ def draw_subgraph(controller_group, component_id, style, prev_node, idx):
 
             input_node = pydot.Node(
                 component_id,
-                label=arg,
                 color="black",
-                shape="ellipse",
-                fontsize=10,
-                style=nd_style,
                 fontname="helvetica",
+                fontsize=10,
+                label=arg,
+                shape="ellipse",
+                style=nd_style,
             )
             subgraph.add_node(input_node)
             component_id += 1

test/python/visualization/references/pass_manager_standard.dot

@@ -13,7 +13,7 @@ fontname=helvetica;
 label="[1] ConditionalController";
 labeljust=l;
 4 [color=red, fontname=helvetica, label=TrivialLayout, shape=rectangle];
-5 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+5 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 5 -> 4;
 1 -> 4;
 }
@@ -23,7 +23,7 @@ fontname=helvetica;
 label="[2] ";
 labeljust=l;
 7 [color=red, fontname=helvetica, label=FullAncillaAllocation, shape=rectangle];
-8 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+8 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 8 -> 7;
 4 -> 7;
 }
@@ -41,13 +41,13 @@ fontname=helvetica;
 label="[4] ";
 labeljust=l;
 12 [color=blue, fontname=helvetica, label=BasisTranslator, shape=rectangle];
-13 [color=black, fontname=helvetica, fontsize=10, label=equivalence_library, shape=ellipse, style=solid];
+13 [color=black, fontname=helvetica, fontsize=10, label="equivalence_library", shape=ellipse, style=solid];
 13 -> 12;
-14 [color=black, fontname=helvetica, fontsize=10, label=target_basis, shape=ellipse, style=solid];
+14 [color=black, fontname=helvetica, fontsize=10, label="target_basis", shape=ellipse, style=solid];
 14 -> 12;
 15 [color=black, fontname=helvetica, fontsize=10, label=target, shape=ellipse, style=dashed];
 15 -> 12;
-16 [color=black, fontname=helvetica, fontsize=10, label=min_qubits, shape=ellipse, style=dashed];
+16 [color=black, fontname=helvetica, fontsize=10, label="min_qubits", shape=ellipse, style=dashed];
 16 -> 12;
 10 -> 12;
 }
@@ -57,9 +57,9 @@ fontname=helvetica;
 label="[5] ";
 labeljust=l;
 18 [color=red, fontname=helvetica, label=CheckMap, shape=rectangle];
-19 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+19 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 19 -> 18;
-20 [color=black, fontname=helvetica, fontsize=10, label=property_set_field, shape=ellipse, style=dashed];
+20 [color=black, fontname=helvetica, fontsize=10, label="property_set_field", shape=ellipse, style=dashed];
 20 -> 18;
 12 -> 18;
 }
@@ -79,7 +79,7 @@ fontname=helvetica;
 label="[7] ";
 labeljust=l;
 25 [color=blue, fontname=helvetica, label=GateDirection, shape=rectangle];
-26 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+26 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 26 -> 25;
 27 [color=black, fontname=helvetica, fontsize=10, label=target, shape=ellipse, style=dashed];
 27 -> 25;

test/python/visualization/references/pass_manager_style.dot

@@ -13,7 +13,7 @@ fontname=helvetica;
 label="[1] ConditionalController";
 labeljust=l;
 4 [color=red, fontname=helvetica, label=TrivialLayout, shape=rectangle];
-5 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+5 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 5 -> 4;
 1 -> 4;
 }
@@ -23,7 +23,7 @@ fontname=helvetica;
 label="[2] ";
 labeljust=l;
 7 [color=red, fontname=helvetica, label=FullAncillaAllocation, shape=rectangle];
-8 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+8 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 8 -> 7;
 4 -> 7;
 }
@@ -41,13 +41,13 @@ fontname=helvetica;
 label="[4] ";
 labeljust=l;
 12 [color=blue, fontname=helvetica, label=BasisTranslator, shape=rectangle];
-13 [color=black, fontname=helvetica, fontsize=10, label=equivalence_library, shape=ellipse, style=solid];
+13 [color=black, fontname=helvetica, fontsize=10, label="equivalence_library", shape=ellipse, style=solid];
 13 -> 12;
-14 [color=black, fontname=helvetica, fontsize=10, label=target_basis, shape=ellipse, style=solid];
+14 [color=black, fontname=helvetica, fontsize=10, label="target_basis", shape=ellipse, style=solid];
 14 -> 12;
 15 [color=black, fontname=helvetica, fontsize=10, label=target, shape=ellipse, style=dashed];
 15 -> 12;
-16 [color=black, fontname=helvetica, fontsize=10, label=min_qubits, shape=ellipse, style=dashed];
+16 [color=black, fontname=helvetica, fontsize=10, label="min_qubits", shape=ellipse, style=dashed];
 16 -> 12;
 10 -> 12;
 }
@@ -57,9 +57,9 @@ fontname=helvetica;
 label="[5] ";
 labeljust=l;
 18 [color=green, fontname=helvetica, label=CheckMap, shape=rectangle];
-19 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+19 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 19 -> 18;
-20 [color=black, fontname=helvetica, fontsize=10, label=property_set_field, shape=ellipse, style=dashed];
+20 [color=black, fontname=helvetica, fontsize=10, label="property_set_field", shape=ellipse, style=dashed];
 20 -> 18;
 12 -> 18;
 }
@@ -79,7 +79,7 @@ fontname=helvetica;
 label="[7] ";
 labeljust=l;
 25 [color=blue, fontname=helvetica, label=GateDirection, shape=rectangle];
-26 [color=black, fontname=helvetica, fontsize=10, label=coupling_map, shape=ellipse, style=solid];
+26 [color=black, fontname=helvetica, fontsize=10, label="coupling_map", shape=ellipse, style=solid];
 26 -> 25;
 27 [color=black, fontname=helvetica, fontsize=10, label=target, shape=ellipse, style=dashed];
 27 -> 25;

test/python/visualization/test_pass_manager_drawer.py

@@ -42,6 +42,8 @@ from .visualization import QiskitVisualizationTestCase, path_to_diagram_referenc
 class TestPassManagerDrawer(QiskitVisualizationTestCase):
     """Qiskit pass manager drawer tests."""
 
+    maxDiff = None
+
     def setUp(self):
         super().setUp()
         coupling = [[0, 1], [1, 2], [2, 3], [3, 4], [4, 5], [5, 6]]