Add specs for pandoc markdown renderer

spec/renderers_spec.moon

@@ -0,0 +1,71 @@
+factory = require "spec.factory"
+
+import trim from require "sitegen.common"
+
+flatten_html = (html) ->
+  trim (html\gsub "%>%s+%<", "><")
+
+describe "renderers", ->
+  render_for_site = (site, renderer, str, meta={}, page) ->
+    page or= factory.Page(:site)
+    page.render_fn, page.meta = renderer\load str
+    page.meta.template = false
+    for k,v in pairs meta
+      page.meta[k] = v
+    page\render!
+
+  describe "renderers.markdown", ->
+    local site, renderer
+
+    render = (...) -> render_for_site site, renderer, ...
+
+    before_each ->
+      MarkdownRenderer = require "renderers.markdown"
+      site = factory.Site!
+      renderer = MarkdownRenderer site
+
+    it "syntax highlights some code", ->
+      out = flatten_html render [[
+```lua
+print("hello world")
+```]]
+
+      assert.same [[<div class="highlight"><pre><span></span><code><span class="py-nb">print</span><span class="py-p">(</span><span class="py-s2">&quot;hello world&quot;</span><span class="py-p">)</span></code></pre></div>]], out
+
+    it "doesnt highlight code inside of a cosmo template", ->
+      site.user_vars.hello = (_, args) ->
+        { template } = args
+        template
+
+      out = flatten_html render [=[
+  ```lua
+  print 5
+  ```
+  $hello{[[
+    ```lua
+    print thing
+    ```
+  ]]}]=]
+
+      assert.same [=[<div class="highlight"><pre><span></span><code><span class="py-nb">print</span><span class="py-mi">5</span></code></pre></div><p>
+    ```lua
+    print thing
+    ```
+  </p>]=], out
+
+    it "doesn't highlight unrecognized code languages", ->
+      out = flatten_html render [[
+  ```snickerdoodle
+  this code block has an unknown label
+  ```]]
+
+      assert.same [[<div class="sourceCode"><pre class="sourceCode"><code>this code block has an unknown label</code></pre></div>]], out
+
+    it "defaults to pandoc highlighting when pygments fails to recognize code language", ->
+      out = flatten_html render [[
+```heex
+<.greet name="Jane" />
+```]]
+
+      assert.same [[<div class="sourceCode" id="cb1"><pre
+class="sourceCode heex"><code class="sourceCode elixir"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="op">&lt;.</span>greet name<span class="op">=</span><span class="st">&quot;Jane&quot;</span><span class="op">/&gt;</span></span></code></pre></div>]], out