What are you proposing?

Add a native "Compare with Branch" feature. This would allow users to select another branch and view side-by-side (or inline) comparisons of files directly within Zed.

Why does this matter?

Currently, Zed lacks a full-window GUI diff viewer. To compare current work against another branch, users are forced to use the terminal, terminal UIs like lazygit, or completely separate external GUI diff tools.

Building this natively solves the context-switching problem. It makes reviewing cross-branch changes, doing self-code-reviews, and understanding project history seamless without ever leaving the editor.

Are there any examples or context?

• JetBrains IDEs: The "Compare with Branch" feature opens a dedicated side-by-side split view showing exactly what changed between the current working tree and the selected branch.
• VS Code: The built-in Source Control diff viewer, as well as the CLI command code --diff fileA fileB, which opens a native diff tab.

Possible approach

1. Command Palette Action: Add a Git: Compare with Branch command that opens a branch picker. Selecting a branch opens a list of changed files, which launch into a side-by-side read-only diff tab when clicked.
2. CLI Support: Introduce a zed --diff <path1> <path2> command. Even before a full branch-comparison GUI is built, this would allow users of git difftool or lazygit to route their diff views directly into Zed's UI.