6 files changed, 31 insertions, 16 deletions
diff --git a/scripts/check_formatting.py b/scripts/check_formatting.py
index e3342603..27daebe5 100755
--- a/scripts/check_formatting.py
+++ b/scripts/check_formatting.py
@@ -20,7 +20,7 @@ def run_formatter(command, good_path):
     """Run the formatter and compare the output."""
 
     with subprocess.Popen(
-        command, stderr=DEVNULL, stdout=PIPE, encoding="utf-8"
+        command, encoding="utf-8", stderr=DEVNULL, stdout=PIPE
     ) as proc:
         out = list(proc.stdout)
 
diff --git a/scripts/serd_bench.py b/scripts/serd_bench.py
index d964984f..8e176322 100755
--- a/scripts/serd_bench.py
+++ b/scripts/serd_bench.py
@@ -192,10 +192,13 @@ def run(progs, n_min, n_max, step):
                 with open(filename(n) + ".out", "w") as out:
                     sys.stderr.write(cmd + "\n")
                     proc = subprocess.Popen(
-                        cmd.split(), stdout=out, stderr=subprocess.PIPE
+                        cmd.split(),
+                        encoding="utf-8",
+                        stdout=out,
+                        stderr=subprocess.PIPE,
                     )
 
-                    time, memory = parse_time(proc.communicate()[1].decode())
+                    time, memory = parse_time(proc.communicate()[1])
                     rows["time"] += ["%.07f" % time]
                     rows["throughput"] += ["%d" % (n / time)]
                     rows["memory"] += [str(memory)]
diff --git a/test/run_suite.py b/test/run_suite.py
index 3811a74e..84c74dd1 100755
--- a/test/run_suite.py
+++ b/test/run_suite.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# Copyright 2022-2023 David Robillard <d@drobilla.net>
+# Copyright 2022-2025 David Robillard <d@drobilla.net>
 # SPDX-License-Identifier: ISC
 
 """Run a "simple" one-pass RDF-based test suite for serd."""
@@ -43,7 +43,7 @@ def run_eval_test(base_uri, command, in_path, good_path, out_path):
     syntax = util.syntax_from_path(out_path)
     command = command + ["-o", syntax, in_path, base_uri]
 
-    with subprocess.Popen(command, stdout=PIPE, encoding="utf-8") as proc:
+    with subprocess.Popen(command, encoding="utf-8", stdout=PIPE) as proc:
         out = list(proc.stdout)
 
     with open(good_path, "r", encoding="utf-8") as good:
@@ -65,7 +65,9 @@ def run_negative_test(base_uri, command, in_path, ignore):
         raise RuntimeError("Input file missing: " + in_path)
 
     command = command + [in_path, base_uri]
-    proc = subprocess.run(command, check=False, stderr=PIPE, stdout=DEVNULL)
+    proc = subprocess.run(
+        command, check=False, encoding="utf-8", stderr=PIPE, stdout=DEVNULL
+    )
 
     if not ignore and proc.returncode == 0:
         util.error("Unexpected successful return: " + in_path)
diff --git a/test/serd_test_util/__init__.py b/test/serd_test_util/__init__.py
index ad417762..c38100b5 100644
--- a/test/serd_test_util/__init__.py
+++ b/test/serd_test_util/__init__.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# Copyright 2022-2023 David Robillard <d@drobilla.net>
+# Copyright 2022-2025 David Robillard <d@drobilla.net>
 # SPDX-License-Identifier: ISC
 
 """Utilities for data-driven tests."""
@@ -157,12 +157,14 @@ def load_rdf(filename, base_uri, command_prefix):
 
     cmd = command_prefix + [filename, base_uri]
     proc = subprocess.run(
-        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=True
+        cmd,
+        encoding="utf-8",
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        check=True,
     )
     for line in proc.stdout.splitlines():
-        matches = re.match(
-            r"<([^ ]*)> <([^ ]*)> <([^ ]*)> \.", line.decode("utf-8")
-        )
+        matches = re.match(r"<([^ ]*)> <([^ ]*)> <([^ ]*)> \.", line)
         if matches:
             s, p, o = (matches.group(1), matches.group(2), matches.group(3))
             if s not in model:
diff --git a/test/test_quiet.py b/test/test_quiet.py
index 676284bb..ff53e26e 100755
--- a/test/test_quiet.py
+++ b/test/test_quiet.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# Copyright 2022 David Robillard <d@drobilla.net>
+# Copyright 2022-2025 David Robillard <d@drobilla.net>
 # SPDX-License-Identifier: ISC
 
 """Test quiet command-line option."""
@@ -13,7 +13,11 @@ import serd_test_util as util
 args = util.wrapper_args(__doc__, True)
 command = shlex.split(args.wrapper) + [args.serdi, "-q", args.input]
 proc = subprocess.run(
-    command, check=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE
+    command,
+    encoding="utf-8",
+    check=False,
+    stdout=subprocess.PIPE,
+    stderr=subprocess.PIPE,
 )
 
 assert proc.returncode != 0
diff --git a/test/test_write_error.py b/test/test_write_error.py
index b62f981a..93b0249a 100755
--- a/test/test_write_error.py
+++ b/test/test_write_error.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-# Copyright 2022-2023 David Robillard <d@drobilla.net>
+# Copyright 2022-2025 David Robillard <d@drobilla.net>
 # SPDX-License-Identifier: ISC
 
 """Test errors writing to a file."""
@@ -18,11 +18,15 @@ command = shlex.split(args.wrapper) + [args.serdi, args.input]
 if os.path.exists("/dev/full"):
     with open("/dev/full", "w", encoding="utf-8") as out:
         proc = subprocess.run(
-            command, check=False, stdout=out, stderr=subprocess.PIPE
+            command,
+            encoding="utf-8",
+            check=False,
+            stdout=out,
+            stderr=subprocess.PIPE,
         )
 
     assert proc.returncode != 0
-    assert "error" in proc.stderr.decode("utf-8")
+    assert "error" in proc.stderr
 
 else:
     sys.stderr.write("warning: /dev/full not present, skipping test")