One file can contain two changes that belong in different commits. Patch staging lets you choose a hunk without staging the entire file. Read the proposed lines before answering the picker. Selecting every hunk can accidentally include an unrelated experiment. In this simulator the hunk controls send a patch answer, and you can also use the displayed local command. The check compares staged and working content, so leaving the other change unstaged is part of the result. A yes answer stages the proposed change; a no answer leaves that hunk in the working tree. After both choices, compare the cached diff with the ordinary diff to confirm which half remains uncommitted.