diff --git a/platformio/commands/check/command.py b/platformio/commands/check/command.py
index d1f01f5c..3d430b02 100644
--- a/platformio/commands/check/command.py
+++ b/platformio/commands/check/command.py
@@ -67,7 +67,7 @@ def cli(
     silent,
     verbose,
     json_output,
-    fail_on_defect
+    fail_on_defect,
 ):
     app.set_session_var("custom_project_conf", project_conf)
 
@@ -140,7 +140,9 @@ def cli(
                 result["succeeded"] = rc == 0
                 if fail_on_defect:
                     result["succeeded"] = rc == 0 and not any(
-                        d.severity == DefectItem.SEVERITY_HIGH for d in result["defects"])
+                        d.severity == DefectItem.SEVERITY_HIGH
+                        for d in result["defects"]
+                    )
                 result["stats"] = collect_component_stats(result)
                 results.append(result)
 
@@ -149,8 +151,10 @@ def cli(
 
                 if not json_output and not silent:
                     if rc != 0:
-                        click.echo("Error: %s failed to perform check! Please "
-                            "examine tool output in verbose mode." % tool)
+                        click.echo(
+                            "Error: %s failed to perform check! Please "
+                            "examine tool output in verbose mode." % tool
+                        )
                     elif not result["defects"]:
                         click.echo("No defects found")
                     print_processing_footer(result)
diff --git a/tests/commands/test_check.py b/tests/commands/test_check.py
index 028798ef..b079aaad 100644
--- a/tests/commands/test_check.py
+++ b/tests/commands/test_check.py
@@ -287,11 +287,11 @@ def test_check_fails_on_defects_only_with_flag(clirunner, tmpdir):
     tmpdir.join("platformio.ini").write(config)
     tmpdir.mkdir("src").join("main.cpp").write(TEST_CODE)
 
-    default_result = clirunner.invoke(
-        cmd_check, ["--project-dir", str(tmpdir)])
+    default_result = clirunner.invoke(cmd_check, ["--project-dir", str(tmpdir)])
 
     result_with_flag = clirunner.invoke(
-        cmd_check, ["--project-dir", str(tmpdir), "--fail-on-defect"])
+        cmd_check, ["--project-dir", str(tmpdir), "--fail-on-defect"]
+    )
 
     assert default_result.exit_code == 0
     assert result_with_flag.exit_code != 0