10. File Uploads & Downloads

This directly sets file(s) on an <input type="file"> element without touching the OS-level native file picker dialog at all.

.set_input_files(paths)

What it does: Sets file(s) on a file input element directly, bypassing the native OS file picker dialog.

Types/params:

Pointers: Works even on hidden file inputs (a styled "Upload" button triggering a hidden <input type="file">) — no OS-level automation needed.

download = download_info.value

As with new-tab handling, the with ... expect_download() pattern registers the listener before the triggering click.

• paths — one of:
• A single string path → uploads one file
• A list of string paths → uploads multiple files (if the input supports multiple)
• An empty list [] → clears the current selection

# Single file

What it does: Context manager that captures a triggered file download.

Types/params:

Pointers: Must wrap the triggering click, same race-condition reasoning as expect_page().

What it does: Saves the downloaded file to a chosen path / exposes the browser's suggested filename.

Types/params:

Pointers: Check suggested_filename to assert naming logic; save and inspect contents when you need to verify actual file data, not just that a download happened.

• Used as a context manager: with page.expect_download() as info:
• info.value (after the block) → the Download object
• .save_as(path) → path (string, required) — destination file path on disk
• .suggested_filename → no params, read-only string property

download.save_as(path) / download.suggested_filename