First commit: this starts off on a pretty solid foot because we iterated on it a lot already.

test/content.js

@@ -0,0 +1,121 @@
+/* global it describe */
+var remark = require('remark');
+var expect = require('expect');
+var visit = require('unist-util-visit');
+var select = require('unist-util-select');
+var fs = require('fs');
+var GithubSlugger = require('github-slugger');
+var { linter } = require('eslint');
+var allPages = require('../src/content');
+
+var slugger = new GithubSlugger();
+var actionVerbs = /^(List|Retrieve|Remove|Search|Create|Delete)/;
+
+let isSectionTitle = (title) => title.match(actionVerbs);
+let getSectionTitle = chunk => chunk[0].children[0].value;
+
+function extractSections(ast) {
+  return ast.children.reduce((chunks, node) => {
+    if (node.type === 'heading' && node.depth === 1) {
+      return chunks;
+    } else if (node.type === 'heading' && node.depth === 3) {
+      chunks.push([node]);
+    } else {
+      chunks[chunks.length - 1].push(node);
+    }
+    return chunks;
+  }, [[]])
+  .filter(chunk => chunk.length)
+  .filter(chunk => {
+    return isSectionTitle(getSectionTitle(chunk));
+  })
+  .map(chunk => ({ type: 'root', children: chunk }));
+}
+
+var slugs = {};
+describe('global rules', () => {
+  var ast = remark.parse(allPages);
+  var seen = {};
+  /**
+   * Check that titles are unique. This is to ensure that permalinks
+   * are unique.
+   */
+
+  visit(ast, 'heading', node => {
+    slugs['#' + slugger.slug(node.children[0].value)] = true;
+    if (node.depth > 3) return;
+    var {  value } = node.children[0];
+    it('title ' + value + ' is unique', () => {
+      expect(seen.hasOwnProperty(value))
+        .toEqual(false, 'Title `' + value + '` should be unique');
+      seen[value] = true;
+    });
+  });
+
+});
+
+describe('content', () => {
+  fs.readdirSync('./content').forEach(function(file) {
+    describe(file, () => {
+      var content = fs.readFileSync('./content/' + file, 'utf8');
+      var ast = remark.parse(content);
+
+      it('links are valid', function() {
+        visit(ast, 'link', node => {
+          if (node.href && node.href[0] === '#') {
+            expect(slugs[node.href])
+              .toExist('A link to ' + node.href + ' at ' +
+                  node.position.start.line + ' of ' + file + ' was invalid');
+          }
+        });
+      });
+
+      it('has h2 title', function() {
+        expect(ast.children[0].type).toEqual('heading');
+        expect(ast.children[0].depth).toEqual(2);
+      });
+
+      it('has API description', function() {
+        expect(ast.children[1].type === 'paragraph' || ast.children[1].type === 'html').toEqual(true);
+      });
+
+      it('has valid json', () => {
+        select(ast, 'code[lang=json]').forEach(node => {
+          expect(function() {
+            JSON.parse(node.value);
+          }).toNotThrow(null, 'a JSON code block at L:' +
+            node.position.start.line + ' of ' + file + ' was invalid');
+        });
+      });
+
+      it('has valid javascript', () => {
+        select(ast, 'code[lang=javascript]').forEach(node => {
+          var messages = linter.verify(node.value);
+          expect(messages).toEqual([], 'a JS code block at L:' +
+            node.position.start.line + ' of ' + file + ' was invalid');
+        });
+      });
+
+      extractSections(ast).forEach(chunk => {
+        describe(getSectionTitle(chunk.children), function() {
+          it('has an endpoint and that endpoint has a valid method', () => {
+            var endpoint = select(chunk, 'code[lang=endpoint]');
+            expect(endpoint.length).toBeGreaterThan(0);
+            expect(endpoint[0].value.toString()).toMatch(/^(PUT|POST|GET|DELETE|PATCH)/);
+          });
+          if (!file.match(/(style|static_gl|maps|static_classic|uploads)/)) {
+            it('has python example', () => {
+              expect(select(chunk, 'code[lang=python]').length).toBeGreaterThan(0);
+            });
+            it('has js example', () => {
+              expect(select(chunk, 'code[lang=javascript]').length).toBeGreaterThan(0);
+            });
+            it('has curl example', () => {
+              expect(select(chunk, 'code[lang=curl]').length).toBeGreaterThan(0);
+            });
+          }
+        });
+      });
+    });
+  });
+});