Add verification script

Makefile

@@ -213,8 +213,8 @@ check-translate: locale/circuitpython.pot $(wildcard locale/*.po)
 	$(PYTHON) tools/check_translations.py $^
 
 stubs:
-	rst2pyi $(VALIDATE) shared-bindings/ $(STUBDIR)
-	python setup.py sdist
+	python tools/extract_pyi.py shared-bindings/ $(STUBDIR)
+	#python setup.py sdist
 
 update-frozen-libraries:
 	@echo "Updating all frozen libraries to latest tagged version."

tools/extract_pyi.py

@@ -0,0 +1,46 @@
+import os
+import sys
+import astroid
+import traceback
+
+top_level = sys.argv[1].strip("/")
+stub_directory = sys.argv[2]
+
+if top_level.count("/") == 1:
+    top_level, module = top_level.split("/")
+    modules = [module]
+else:
+    modules = os.listdir(top_level)
+    modules = sorted(modules)
+
+ok = 0
+total = 0
+for module in modules:
+    module_path = os.path.join(top_level, module)
+    if not os.path.isdir(module_path):
+        continue
+    pyi_lines = []
+    for class_file in os.listdir(module_path):
+        class_path = os.path.join(module_path, class_file)
+        with open(class_path, "r") as f:
+            for line in f:
+                if line.startswith("//| "):
+                    pyi_lines.append(line[4:])
+
+    stub_filename = os.path.join(stub_directory, module + ".pyi")
+    print(stub_filename)
+    stub_contents = "".join(pyi_lines)
+    with open(stub_filename, "w") as f:
+        f.write(stub_contents)
+
+    # Validate that the module is a parseable stub.
+    total += 1
+    try:
+        astroid.parse(stub_contents)
+        ok += 1
+    except astroid.exceptions.AstroidSyntaxError as e:
+        e = e.__cause__
+        traceback.print_exception(type(e), e, e.__traceback__)
+    print()
+
+print(f"{ok} ok out of {total}")