From 46fe5a9336983e0481944a166c92acac1a816efc Mon Sep 17 00:00:00 2001
From: Alexandru Fikl <alexfikl@gmail.com>
Date: Sun, 26 Jul 2026 10:25:09 +0300
Subject: [PATCH 1/2] fix: new ruff
 implicit-string-concatenation-in-collection-literal

---
 pytential/symbolic/compiler.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/pytential/symbolic/compiler.py b/pytential/symbolic/compiler.py
index e17a2589f..9847f6d2d 100644
--- a/pytential/symbolic/compiler.py
+++ b/pytential/symbolic/compiler.py
@@ -333,8 +333,9 @@ def dot_dataflow_graph(
     node_names: dict[Statement, str] = {}
 
     result = [
-            'initial [label="initial"]'
-            'result [label="result"]']
+        'initial [label="initial"];',
+        'result [label="result"];',
+    ]
 
     for num, insn in enumerate(code.statements):
         node_name = f"node{num}"
@@ -380,7 +381,7 @@ def gen_expr_arrow(expr: Expression, target_node: str) -> None:
     else:
         gen_expr_arrow(code_res, "result")
 
-    return "digraph dataflow {\n%s\n}\n" % "\n".join(result)
+    return "digraph dataflow {\n  %s\n}\n" % "\n  ".join(result)
 
 # }}}
 

From 8280ff0679680514866a42bf3b7bae6bf7d90a63 Mon Sep 17 00:00:00 2001
From: Alexandru Fikl <alexfikl@gmail.com>
Date: Sun, 26 Jul 2026 10:25:29 +0300
Subject: [PATCH 2/2] test: add test for dot_dataflow_graph

---
 test/test_tools.py | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/test/test_tools.py b/test/test_tools.py
index bbe85ce0e..5761015ee 100644
--- a/test/test_tools.py
+++ b/test/test_tools.py
@@ -288,6 +288,48 @@ def test_add_geometry_to_collection(actx_factory: ArrayContextFactory):
 # }}}
 
 
+# {{{ test_dot_dataflow_graph
+
+def test_dot_dataflow_graph() -> None:
+    from pymbolic.primitives import Variable
+
+    from pytential.symbolic.compiler import Assign, Code, dot_dataflow_graph
+    from pytential.symbolic.mappers import DependencyMapper
+
+    dep_mapper = DependencyMapper(composite_leaves=False)
+
+    x = Variable("x")
+    y = Variable("y")
+    z = Variable("z")
+
+    stmt = Assign(names=("w",), exprs=(x + y,), priority=0)
+    code = Code(
+        inputs={"x", "y"},
+        schedule=[(stmt, set())],
+        result=z,
+    )
+
+    dot = dot_dataflow_graph(dep_mapper, code)
+    logger.info("dot graph:\n%s", dot)
+    assert "digraph dataflow" in dot
+
+    import shutil
+    if shutil.which("dot") is None:
+        return
+
+    import subprocess
+
+    result = subprocess.run(  # ruff: ignore[subprocess-run-without-check]
+        ["dot", "-Tsvg"],
+        input=dot,
+        capture_output=True,
+        text=True,
+    )
+    assert result.returncode == 0
+
+# }}}
+
+
 # You can test individual routines by typing
 # $ python test_tools.py 'test_routine()'