Conflict Lens
English | 日本語
A VS Code extension that highlights code where your edits could conflict with the base branch.
It periodically checks the remote base branch and highlights code in the file you have open that has been changed on the base branch.
You can also review the diff against the base branch on the spot.
- Catch conflict-prone code seamlessly while you work
- Spot clashes with other developers' changes before they happen
- Simulate the actual conflict to preview it
Table of Contents
Features
Visualizing changes on the base branch
It periodically checks the remote base branch and highlights any lines that have been changed upstream.
By default it runs git ls-remote every 5 minutes (or when you focus a file) to check for updates.
When an update is found, it shows a prompt to update the base branch (clicking OK runs git fetch for the base branch only).
You can also check the upstream changes from the hover menu on a highlighted line.
Requirements
- VS Code 1.74 or later
- Git 2.30 or later
Installation
From the Marketplace
- Open the Extensions view in VS Code (
Cmd/Ctrl + Shift + X)
- Search for "Conflict Lens"
- Click Install
Or install from the command line:
code --install-extension Masa-Shin.conflict-lens
You can also open the Marketplace page directly.
Usage
- Open a git repository in VS Code
- Click
Conflict Lens in the bottom-right of the status bar and select a base branch (not needed if one is already selected)
This enables the features.
About automatic base branch detection
When you install the extension, it auto-detects the base branch in the following order.
- The remote's default branch (the target of
refs/remotes/<remoteName>/HEAD)
<remoteName>/main<remoteName>/master
If none is found, it shows (no base) and the features are disabled.
More Features
Viewing the list of changed files
Running Conflict Lens: Show Changed Files lists the files changed on the base branch at the top of the screen; selecting one opens that file.
Viewing details in the diff editor
Compare the current content on the base branch with your local content side by side.
How to open:
- Click the "Show base changes" link in the hover menu on a highlighted line
- Run
Conflict Lens: Show Base Branch Changes from the Command Palette
Previewing the conflict
Preview the conflict that would occur in a separate tab. If there is no conflict, it notifies you with "No conflict."
How to open:
- Click the "Preview conflict" link in the hover menu on a highlighted line
- Run
Conflict Lens: Preview Conflict from the Command Palette
Temporarily disabling
Conflict Lens: Toggle switches the highlighting on and off.
Configuration Reference
| Key |
Default |
Range |
Description |
conflictLens.enabled |
true |
bool |
Turn the whole extension on/off |
conflictLens.remoteName |
origin |
string |
Remote name used for auto-detection |
conflictLens.showOverviewRuler |
true |
bool |
Show highlight positions on the scrollbar |
conflictLens.showFileDecorationBadges |
true |
bool |
Show badges in the Explorer |
conflictLens.remoteCheckIntervalMinutes |
5 |
0-1440 |
Interval for checking remote updates (minutes). 0 to disable |
You can override the highlight colors in workbench.colorCustomizations in your VS Code settings.json. The available keys are:
conflictLens.changedLineBackground — background color for lines changed on the base (yellow by default)
Command Reference
| Command |
Description |
Conflict Lens: Enable |
Enable |
Conflict Lens: Disable |
Disable |
Conflict Lens: Toggle |
Toggle enabled/disabled |
Conflict Lens: Refresh |
Discard the cache and recompute |
Conflict Lens: Select Base Branch |
Select the base branch |
Conflict Lens: Show Changed Files |
List of changed files |
Conflict Lens: Show Base Branch Changes |
Show the diff between the current file and the base branch |
Conflict Lens: Preview Conflict |
Show the expected conflict in a read-only preview |
Conflict Lens: Show Output Channel |
Show the logs |
Troubleshooting
You can check the logs with Conflict Lens: Show Output Channel.
No highlights appear
When the feature is halted, Conflict Lens in the status bar is shown with a strikethrough. Hover over the item to see the reason.
- Base branch not detected → specify one with
Select Base Branch
- In the middle of a rebase or merge → finish or abort it
- Not on any branch (detached HEAD) → halted, since you rarely work in this state. Checking out a branch resumes it
- Git not found, or not a git repository
If there is no strikethrough but still no highlights, there may simply be no diff against the base. You can check with the following command.
git log --oneline HEAD...origin/main
A setting change is not reflected
Setting changes should apply immediately, but if something still seems off, try Conflict Lens: Refresh.
Known Limitations
- In a multi-root workspace, only the first folder is watched
- Files inside submodules and symbolic links are not covered
- Very large files (over 15,000 lines or about 1.5M characters) are not highlighted
Development
Setting up the development environment
Running the following launches a separate VS Code window with the built extension loaded, so you can try it out.
npm run dev
License
MIT
