added test cases

jekyll-geolexica.gemspec

@@ -47,6 +47,8 @@ Gem::Specification.new do |spec|
   # Pin logger to <= 1.5.3 due to incompatibility of logger 1.6.0 with Jekyll 4.3.2
   spec.add_runtime_dependency "logger", "<= 1.5.3"
   spec.add_runtime_dependency "relaton"
+  spec.add_runtime_dependency "unitsml"
+  spec.add_runtime_dependency "plurimath"
 
   # Zeitwerk::Loader#push_dir supports :namespace argument from v. 2.4.
   spec.add_runtime_dependency "zeitwerk", "~> 2.4"

lib/jekyll/geolexica.rb

@@ -3,6 +3,7 @@
 
 require "jekyll"
 require "glossarist"
+require "plurimath"
 
 module Jekyll
   module Geolexica

lib/jekyll/geolexica/hooks.rb

@@ -33,7 +33,7 @@ def convert_math(page)
         page.output.gsub!(/stem:\[([^\]]*?)\]/) do
           ascii_equation = CGI.unescapeHTML(Regexp.last_match[1])
 
-          mathml_equation = Plurimath::Math
+          mathml_equation = ::Plurimath::Math
                               .parse(ascii_equation, :asciimath)
                               .to_mathml
 

spec/unit/jekyll/geolexica/hooks_spec.rb

@@ -0,0 +1,70 @@
+# (c) Copyright 2020 Ribose Inc.
+#
+
+RSpec.describe ::Jekyll::Geolexica::Hooks do
+  subject do
+    w = Object.new
+    w.extend(described_class)
+    w
+  end
+
+  let(:page) do
+    instance_double(
+      Jekyll::Geolexica::ConceptPage::HTML,
+      output: page_output,
+      html?: is_html,
+    )
+  end
+
+  describe ".convert_math" do
+    context "when page is HTML" do
+      let(:is_html) { true }
+
+      let(:page_output) do
+        "foo stem:[a_2] bar"
+      end
+
+      let(:expected_output) do
+        <<~OUTPUT.strip
+          foo <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline">
+            <mstyle displaystyle="true">
+              <msub>
+                <mi>a</mi>
+                <mn>2</mn>
+              </msub>
+            </mstyle>
+          </math>
+           bar
+        OUTPUT
+      end
+
+      it "should convert stem:[] to MathML" do
+        expect { subject.send(:convert_math, page) }
+          .to change { page.output }
+          .from(page_output)
+          .to(expected_output)
+      end
+    end
+
+    context "when page is not HTML" do
+      let(:is_html) { false }
+
+      let(:page_output) do
+        "foo stem:[a_2] bar"
+      end
+
+      let(:expected_output) do
+        <<~OUTPUT.strip
+          foo <math xmlns=\\"http://www.w3.org/1998/Math/MathML\\" display=\\"inline\\">  <mstyle displaystyle=\\"true\\">    <msub>      <mi>a</mi>      <mn>2</mn>    </msub>  </mstyle></math> bar
+        OUTPUT
+      end
+
+      it "should convert stem:[] to MathML" do
+        expect { subject.send(:convert_math, page) }
+          .to change { page.output }
+          .from(page_output)
+          .to(expected_output)
+      end
+    end
+  end
+end