Update app and tooling

node_modules/@vercel/build-utils/lib/python/ast_parser.py

@@ -0,0 +1,72 @@
+import sys
+import ast
+
+
+def contains_app_or_handler(file_path: str) -> bool:
+    """
+    Check if a Python file contains or exports:
+    - A top-level 'app' callable (e.g., Flask, FastAPI, Sanic apps)
+    - A top-level 'handler' class (e.g., BaseHTTPRequestHandler subclass)
+    """
+    with open(file_path, "r") as file:
+        code = file.read()
+
+    try:
+        tree = ast.parse(code)
+    except SyntaxError:
+        return False
+
+    for node in ast.iter_child_nodes(tree):
+        # Check for top-level assignment to 'app'
+        # e.g., app = Sanic() or app = Flask(__name__) or app = create_app()
+        if isinstance(node, ast.Assign):
+            for target in node.targets:
+                if isinstance(target, ast.Name) and target.id == "app":
+                    return True
+
+        # Check for annotated assignment to 'app'
+        # e.g., app: Sanic = Sanic()
+        if isinstance(node, ast.AnnAssign):
+            if isinstance(node.target, ast.Name) and node.target.id == "app":
+                return True
+
+        # Check for function named 'app'
+        # e.g., def app(environ, start_response): ...
+        if isinstance(node, ast.FunctionDef) and node.name == "app":
+            return True
+
+        # Check for async function named 'app'
+        # e.g., async def app(scope, receive, send): ...
+        if isinstance(node, ast.AsyncFunctionDef) and node.name == "app":
+            return True
+
+        # Check for import of 'app'
+        # e.g., from server import app
+        # e.g., from server import application as app
+        if isinstance(node, ast.ImportFrom):
+            for alias in node.names:
+                # alias.asname is the 'as' name, alias.name is the original name
+                # If aliased, check asname; otherwise check the original name
+                imported_as = alias.asname if alias.asname else alias.name
+                if imported_as == "app":
+                    return True
+
+        # Check for top-level class named 'handler'
+        # e.g., class handler(BaseHTTPRequestHandler):
+        if isinstance(node, ast.ClassDef) and node.name.lower() == "handler":
+            return True
+
+    return False
+
+
+if __name__ == "__main__":
+    if len(sys.argv) != 2:
+        print("Usage: python ast_parser.py <file_path>")
+        sys.exit(1)
+
+    file_path = sys.argv[1]
+    result = contains_app_or_handler(file_path)
+
+    # Exit with 0 if found, 1 if not found
+    sys.exit(0 if result else 1)
+

node_modules/@vercel/build-utils/lib/python/tests/test_ast_parser.py

@@ -0,0 +1,72 @@
+import unittest
+import tempfile
+import os
+import sys
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from ast_parser import contains_app_or_handler
+
+
+class TestContainsAppOrHandler(unittest.TestCase):
+    def _check(self, code: str) -> bool:
+        """Helper to test code snippets without needing fixture files."""
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".py", delete=False) as f:
+            f.write(code)
+            f.flush()
+            try:
+                return contains_app_or_handler(f.name)
+            finally:
+                os.unlink(f.name)
+
+    def test_flask_app(self):
+        self.assertTrue(self._check("from flask import Flask\napp = Flask(__name__)"))
+
+    def test_fastapi_app(self):
+        self.assertTrue(self._check("from fastapi import FastAPI\napp = FastAPI()"))
+
+    def test_sanic_app(self):
+        self.assertTrue(self._check("from sanic import Sanic\napp = Sanic('app')"))
+
+    def test_annotated_app(self):
+        self.assertTrue(self._check("from fastapi import FastAPI\napp: FastAPI = FastAPI()"))
+
+    def test_wsgi_function(self):
+        self.assertTrue(self._check("def app(environ, start_response):\n    pass"))
+
+    def test_asgi_function(self):
+        self.assertTrue(self._check("async def app(scope, receive, send):\n    pass"))
+
+    def test_imported_app(self):
+        self.assertTrue(self._check("from server import app"))
+
+    def test_imported_app_aliased(self):
+        self.assertTrue(self._check("from server import application as app"))
+
+    def test_handler_class(self):
+        self.assertTrue(self._check("class Handler:\n    pass"))
+
+    def test_handler_class_lowercase(self):
+        self.assertTrue(self._check("class handler:\n    pass"))
+
+    def test_no_app_or_handler(self):
+        self.assertFalse(self._check("def hello():\n    return 'world'"))
+
+    def test_app_in_function_not_toplevel(self):
+        # app defined inside a function should NOT match
+        self.assertFalse(self._check("def create():\n    app = Flask(__name__)\n    return app"))
+
+    def test_syntax_error(self):
+        self.assertFalse(self._check("def broken("))
+
+    def test_empty_file(self):
+        self.assertFalse(self._check(""))
+
+    def test_only_comments(self):
+        self.assertFalse(self._check("# just a comment\n# another comment"))
+
+
+if __name__ == "__main__":
+    unittest.main()
+