spec(module_doc): add "Object methods" tests

spec/scraper/module_doc_spec.tl

@@ -231,6 +231,71 @@ describe("Scrap documentation", function()
       })
    end)
 
+   it("should provide a Function node with the `self` as the first positional parameter", function()
+      local ast <const> = get_doc_from_page([[
+            <h2 class="section-header"><a name="Object_methods"></a>Object methods</h2>
+            <dl class="function">
+            <dt>
+               <a class="copy-link js-copy-link" name="swap" href="#swap">🔗</a>
+               <strong
+                  >:swap <span class="function_args"> <b>(</b>tag2<b>)</b></span></strong
+               >
+               <span class="proptype"></span>
+               <span class="baseclass"> </span>
+            </dt>
+            <dd>
+               <h3>Parameters:</h3>
+               <table class="see_also">
+                  <tbody>
+                  <tr class="param_header">
+                     <th>Name</th>
+                     <th></th>
+                     <th>Type(s)</th>
+                     <th>Description</th>
+                  </tr>
+                  <tr>
+                     <td><span class="parameter">tag2</span></td>
+                     <td></td>
+                     <td>
+                        <span class="types"><span class="type">tag</span></span>
+                     </td>
+                     <td class="see_also_description">The second tag</td>
+                  </tr>
+                  </tbody>
+               </table>
+            </dd>
+            </dl>
+         ]], "awful.tag")
+      assert.same(ast, {
+         children = {
+            {
+               children = {},
+               name = "Signal",
+               token = "enum",
+            },
+            {
+               parameters = {
+                  {
+                     types = { "Tag" },
+                     name = "self",
+                     token = "variable",
+                  },
+                  {
+                     types = { "tag" }, -- This needs to be fixed : tag -> Tag
+                     name = "tag2",
+                     token = "variable",
+                  }
+               },
+               return_types = {},
+               name = "swap",
+               token = "function",
+            },
+         },
+         name = "Tag",
+         token = "module",
+      })
+   end)
+
    it("should produce Signal nodes", function()
       local ast <const> = get_doc_from_page([[
             <h2 class="section-header"><a name="Signals"></a>Signals</h2>