dev: Add stylus linting to CI

.github/workflows/js.yml

@@ -39,6 +39,8 @@ jobs:
         run: tools/bin/mage -v jsSDK:lint
       - name: Lint frontend code
         run: tools/bin/mage -v js:lint
+      - name: Lint stylus files
+        run: tools/bin/mage -v styl:lint
       - name: Check for diff
         run: tools/bin/mage git:diff
 

tools/mage/styl.go

@@ -0,0 +1,34 @@
+// Copyright © 2024 The Things Network Foundation, The Things Industries B.V.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ttnmage
+
+import (
+	"fmt"
+
+	"github.com/magefile/mage/mg"
+)
+
+// Styl namespace.
+type Styl mg.Namespace
+
+// Lint runs stylint over frontend styl files.
+func (styl Styl) Lint() error {
+	if mg.Verbose() {
+		fmt.Println("Running stylelint")
+	}
+	return runYarnV("stylelint",
+		"./pkg/webui/**/*.styl",
+	)
+}