Broken code example in docs under Advanced Patterns

[pbhuss]

In the Managing Resources section of Advanced Patterns, there is a code example where a Repo class is used as a context manager to be passed to Context.with_resource.

    class Repo:
        def __init__(self, home=None):
            self.home = os.path.abspath(home or ".")
            self.db = None

        def __enter__(self):
            path = os.path.join(self.home, "repo.db")
            self.db = open_database(path)

        def __exit__(self, exc_type, exc_value, tb):
            self.db.close()

The __enter__ method on Repo currently returns None, which means that the code snippet below is broken since repo is None (the result of __enter__()).

    with Repo() as repo:
        repo.db.query(...)

In the snippet below that, we are also assigning None to ctx.obj, since ctx.with_resource returns the result of calling the resource’s __enter__() method.

    @click.group()
    @click.option("--repo-home", default=".repo")
    @click.pass_context
    def cli(ctx, repo_home):
        ctx.obj = ctx.with_resource(Repo(repo_home))

The fix is to have Repo.__enter__ return self.

• Click version: 8.1.7