VSCode/How To/Diff a file with another branch

• How To Compare a File with Another Branch in VS Code (GitLens)

  • Goal

    • View file differences between a file in your current branch and a file in another Git branch, similar to PyCharm’s “Compare With Branch” feature.

  • Preconditions

    • VS Code installed
    • Git repository initialized
    • VSCode/Extension/GitLens installed

  • Procedure

    • 1. Enable Branches View in GitLens for the VSCode/Panel/Source Control Source Code panel

      • Open Source Control panel (Ctrl+Shift+G / Cmd+Shift+G).
      • Expand the GitLens section.
      • Click the three dots (…) menu.
      • Select Detach Branches View.
        • This makes “Branches” appear as its own section.
        • See also: Anyone else missing Branches and Commits with in Source Control? : r/vscode

    • 2. Diff a Specific File with Another Branch

      • In the Branches view, locate your current branch
      • Click the disclosure triangle for BRANCHNAME
      • Click on the pencil icon in the entry Compare BRANCHNAME
      • Enter the branch name you wish to compare with
      • You should now see an entry underneath like DDD files changed AAA additions (+), DDD deletions (-); click the disclosure triangle
      • Locate the specific file under the disclosure triangle you wish to compare, right click on it
      • Navigate to Open Changes with → Open Changes with Working File.
      • A side-by-side diff opens between your working copy and the file in the other branch.

    • 3. Diff All Files with Other Branch

      • Press on the +/- file button, which has the tooltip "Open All Changes as Working Tree"
      • 

  • Gripes

    • There's no way to bring over individual lines from one side of the diff to the other, the way there is in PyCharm or JetBrains

  • Troubleshooting

    • If Branches aren’t showing, check the GitLens menu → Detach Branches View.

  • References

    • Use the command palette (Ctrl+Shift+P) → GitLens: Compare with Branch for a repo-wide compare.