Add support of Mermaid

2 files changed, 13 insertions, 1 deletions

diff --git a/spec/lib/banzai/filter/mermaid_filter_spec.rb b/spec/lib/banzai/filter/mermaid_filter_spec.rb
new file mode 100644
index 00000000000..532d25e121d
--- /dev/null
+++ b/spec/lib/banzai/filter/mermaid_filter_spec.rb
@@ -0,0 +1,12 @@
+require 'spec_helper'
+
+describe Banzai::Filter::MermaidFilter do
+  include FilterSpecHelper
+
+  it 'adds `js-render-mermaid` class to the `pre` tag' do
+    doc = filter("<pre class='code highlight js-syntax-highlight mermaid' lang='mermaid' v-pre='true'><code>graph TD;\n  A--&gt;B;\n</code></pre>")
+    result = doc.xpath('descendant-or-self::pre').first
+
+    expect(result[:class]).to include('js-render-mermaid')
+  end
+end
diff --git a/spec/lib/banzai/filter/syntax_highlight_filter_spec.rb b/spec/lib/banzai/filter/syntax_highlight_filter_spec.rb
index 5a23e0e70cc..9f2efa05a01 100644
--- a/spec/lib/banzai/filter/syntax_highlight_filter_spec.rb
+++ b/spec/lib/banzai/filter/syntax_highlight_filter_spec.rb
@@ -31,7 +31,7 @@ describe Banzai::Filter::SyntaxHighlightFilter do
 
     it "highlights as plaintext" do
       result = filter('<pre><code lang="ruby">This is a test</code></pre>')
-      expect(result.to_html).to eq('<pre class="code highlight" lang="" v-pre="true"><code>This is a test</code></pre>')
+      expect(result.to_html).to eq('<pre class="code highlight js-syntax-highlight" lang="" v-pre="true"><code>This is a test</code></pre>')
     end
   end
 end