Add custom linter for inline JavaScript to haml_lint (!9742)

.haml-lint.yml

@@ -41,6 +41,9 @@ linters:
   ImplicitDiv:
     enabled: true
 
+  InlineJavaScript:
+    enabled: true
+
   InlineStyles:
     enabled: false
 

changelogs/unreleased/restrict-haml-javascript.yml

@@ -0,0 +1,4 @@
+---
+title: Add custom linter for inline JavaScript to haml_lint
+merge_request: 9742
+author: winniehell

lib/haml_lint/inline_javascript.rb

@@ -0,0 +1,14 @@
+require 'haml_lint/haml_visitor'
+require 'haml_lint/linter'
+require 'haml_lint/linter_registry'
+
+module HamlLint
+  class Linter::InlineJavaScript < Linter
+    include LinterRegistry
+
+    def visit_filter(node)
+      return unless node.filter_type == 'javascript'
+      record_lint(node, 'Inline JavaScript is discouraged (https://docs.gitlab.com/ee/development/gotchas.html#do-not-use-inline-javascript-in-views)')
+    end
+  end
+end

lib/tasks/haml-lint.rake

@@ -1,5 +1,6 @@
 unless Rails.env.production?
   require 'haml_lint/rake_task'
+  require 'haml_lint/inline_javascript'
 
   HamlLint::RakeTask.new
 end