Git read-tree Quiz

Review

1. What does plain `git read-tree <tree>` primarily update?

   It reads tree information into the index without updating working-tree files unless `-u` is used.
2. What does `--empty` do?

   `--empty` makes the index empty; it does not create an object or delete files.
3. What does `--prefix=sub/` do?

   The prefix is applied to the resulting index paths.
4. What is `--index-output=<file>` for?

   It writes the resulting index to the specified file instead of the selected normal index path.
5. What does `--dry-run` guarantee?

   The official manual defines `--dry-run` as checking whether the operation would error without performing the update.
6. In a three-tree `git read-tree -m` merge, what is stage 1?

   Stage 1 represents the original/common-ancestor tree; stages 2 and 3 represent the two sides.
7. What does `-u` add to a successful merge-like `read-tree` operation?

   `-u` asks read-tree to update the working tree after a successful merge operation.
8. Which command is the object-database counterpart that writes a tree from the current index?

   `git write-tree` writes a tree object representing the current index.