1 files changed, 6 insertions, 0 deletions
diff --git a/spec/lib/banzai/filter/ascii_doc_post_processing_filter_spec.rb b/spec/lib/banzai/filter/ascii_doc_post_processing_filter_spec.rb
index 334d5c59828..7af22ea7db1 100644
--- a/spec/lib/banzai/filter/ascii_doc_post_processing_filter_spec.rb
+++ b/spec/lib/banzai/filter/ascii_doc_post_processing_filter_spec.rb
@@ -10,6 +10,12 @@ RSpec.describe Banzai::Filter::AsciiDocPostProcessingFilter do
     expect(result).to eq('<pre data-math-style="inline" class="code math js-render-math">some code</pre><div data-math>and</div>')
   end
 
+  it "adds class for elements with data-mermaid-style" do
+    result = filter('<pre data-mermaid-style="display">some code</pre>').to_html
+
+    expect(result).to eq('<pre data-mermaid-style="display" class="js-render-mermaid">some code</pre>')
+  end
+
   it "keeps content when no data-math-style found" do
     result = filter('<pre>some code</pre><div data-math>and</div>').to_html
     expect(result).to eq('<pre>some code</pre><div data-math>and</div>')