Process, Analyze, and Transform Python Code with ASTs

This tutorial will be a roughly 50/50 split of lecture and exercises. Attendees will get hands-on experience working with ASTs in Python, using only the standard library. By recreating common code-quality checks from scratch, attendees will both learn how common tools work under the hood and how to work with the AST in an easy-to-understand fashion.

Topics covered: - Introduction to the term and concept of Abstract Syntax Trees (ASTs) - Some of the ways ASTs are used by Python itself and by popular tools - Parsing code into an AST and inspecting it - Walking the tree: ast.iter_fields(), ast.iter_child_nodes(), ast.walk() - Modifying the code before running it - Converting an AST into source code again with ast.unparse() and its caveats - Finding missing docstrings - ast.NodeVisitor and ast.NodeTransformer - generic_visit() method — what it does and why we need it using animation - 4 exercise breaks spread throughout accounting for ~45 minutes