Three-Way Folder Comparison
Not in DeltaWalker Classic Free. Three-way comparison is part of the Pro and Oro editions. DeltaWalker Classic Free compares two folders at a time.
Three-way folder comparison works like three-way file comparison, with the same colors for the same kinds of deltas. The units of comparison are files and folders instead of blocks of text.
A three-way folder comparison analyzes the differences between two modified folder hierarchies relative to a third one, their common ancestor or origin.
You typically need it in collaborative projects, where more than one person works on the same branch of files at the same time.
A three-way comparison tells you more than two separate two-way comparisons of each modified hierarchy against the common reference: it shows how the two derived versions relate to each other and to their ancestor. A conflicting change is a case in point. It exists only in a three-way comparison, when the same file has been changed differently in both derived versions.
To open a three-way folder comparison
- Open a new folder comparison window and switch it to the three-way layout: choose Compare Three-Way (Vertical) from the Layout menu on the toolbar, or from the Window menu.
- Select the folders and click Compare. As in three-way file comparison, the ancestor (the Reference) is always in the middle.
- Or reopen a three-way folder comparison from the history at the bottom of File > Folder Comparison.
The following screenshot shows a simple three-way folder comparison with one of each kind of relationship: a deleted file, added files, a file with non-conflicting changes, and a file with conflicting changes.
It shows:
- One triplet of files with conflicting changes: “Different file with conflicts.txt” in each of the compared folders.
- One triplet of files with non-conflicting changes: “Different file.txt” in each of the compared folders.
- Two added files: “First-only file.txt” in the first folder and “Second-only file.txt” in the second.
- One deleted file: “Ancestor-only file.txt”, present only in the ancestor folder.
Three-way comparison goes hand in hand with automatic synchronization of non-conflicting deltas, which merges the changes from the first and second folder hierarchies into their common ancestor by a few simple rules.