Added a unit test for built-in options docs

run_unittests.py

@@ -1008,6 +1008,42 @@ class DataTests(unittest.TestCase):
                 self.assertIn(opt, md)
         self.assertNotIn('b_unknown', md)
 
+    def test_builtin_options_documented(self):
+        '''
+        Test that universal options and base options are documented in
+        Builtin-Options.md.
+        '''
+        md = None
+        with open('docs/markdown/Builtin-options.md') as f:
+            md = f.read()
+        self.assertIsNotNone(md)
+
+        found_entries = set()
+        sections = list(re.finditer(r"^## (.+)$", md, re.MULTILINE)) + [None]
+
+        for s1, s2 in zip(sections[:], sections[1:]):
+            if s1.group(1) == "Universal options":
+                # Extract the content for this section
+                end = s2.start() if s2 is not None else len(md)
+                content = md[s1.end():end]
+                subsections = list(re.finditer(r"^### (.+)$", content, re.MULTILINE)) + [None]
+
+                for sub1, sub2 in zip(subsections[:], subsections[1:]):
+                    if sub1.group(1) == "Directories" or sub1.group(1) == "Core options":
+                        # Extract the content for this subsection
+                        sub_end = sub2.start() if sub2 is not None else len(content)
+                        subcontent = content[sub1.end():sub_end]
+                        # Find the list entries
+                        arches = [m.group(1) for m in re.finditer(r"^\| (\w+) .* \|", subcontent, re.MULTILINE)]
+                        # Drop the header
+                        arches = set(arches[1:])
+
+                        self.assertEqual(len(found_entries & arches), 0)
+                        found_entries |= arches
+            break
+
+        self.assertEqual(found_entries, set(mesonbuild.coredata.builtin_options.keys()))
+
     def test_cpu_families_documented(self):
         with open("docs/markdown/Reference-tables.md") as f:
             md = f.read()