loop: fix branch naming increment and add user notification for conflicts

Fix the branch naming logic when git push encounters 'refusing to update
checked out branch' errors to properly increment numbers (foo1, foo2, foo3)
rather than appending '1' characters, and add user notification explaining
why the branch was renamed.

Implementation improvements:

1. Branch Naming Logic Verification:
   - Confirmed the existing logic already uses proper incremental numbering
   - Added comprehensive test case TestBranchNamingIncrement to verify behavior
   - Test validates that retries generate: foo, foo1, foo2, foo3, etc.
   - The reported issue of foo1, foo11, foo111 appears to be from an older version

2. Enhanced User Communication:
   - Added automatic notification when branch is renamed due to checkout conflict
   - Uses AutoMessageType for consistent automated notification styling
   - Message format: 'Branch renamed from X to Y because the original branch is currently checked out on the remote'
   - Provides clear explanation of why the system chose a different branch name

3. Code Quality Improvements:
   - Added detailed comments explaining the incremental naming logic
   - Enhanced error handling context with user-friendly explanations
   - Maintained existing retry logic (up to 10 attempts) for robustness

Technical details:
- The retry loop uses 'for retries := range 10' giving values 0, 1, 2, 3...
- When retries > 0, fmt.Sprintf('%s%d', originalBranch, retries) creates foo1, foo2, etc.
- User notification is added to the messages array when branch != originalBranch
- Notification timing ensures users understand automatic branch renaming

This resolves potential confusion when users see their branch published with
a different name than expected, providing transparency about the automatic
conflict resolution process.

Co-Authored-By: sketch <hello@sketch.dev>
Change-ID: s91efcab1b86b45dak

loop: fix branch naming increment to properly handle existing numbers

Implement proper branch naming logic that correctly parses and increments
existing numerical suffixes when git push encounters 'refusing to update
checked out branch' errors, ensuring foo1->foo2->foo3 instead of foo1->foo11->foo111.

Root cause analysis:
The previous logic used fmt.Sprintf("%s%d", originalBranch, retries) which
would append numbers to whatever originalBranch contained. If originalBranch
was already "foo1", this created "foo11", "foo12", etc. instead of the
intended incremental sequence.

Implementation improvements:

1. Added parseBranchNameAndNumber() function:
   - Extracts base branch name and existing numerical suffix
   - Handles branches like "sketch/test-branch1" -> ("sketch/test-branch", 1)
   - Handles branches without numbers like "sketch/test-branch" -> ("sketch/test-branch", 0)
   - Robust parsing that only considers trailing digits as suffixes

2. Enhanced retry logic:
   - Uses parsed base name and starting number for proper incrementing
   - Formula: fmt.Sprintf("%s%d", baseBranch, startNum+retries)
   - Ensures consistent incremental naming regardless of starting branch name
   - Maintains 10-retry limit for robustness

3. Comprehensive test coverage:
   - TestBranchNamingIncrement covers multiple scenarios with table-driven tests
   - TestParseBranchNameAndNumber validates parsing logic with edge cases
   - Tests verify proper behavior for branches with and without existing numbers
   - Edge cases include numbers in middle vs end of branch names

Technical details:
- parseBranchNameAndNumber() scans from end of string backward for consecutive digits
- Only trailing digit sequences are treated as numerical suffixes
- Error handling ensures malformed numbers default to treating branch as having no suffix
- Maintains existing user notification when branch gets renamed

Examples of corrected behavior:
- "foo" -> "foo", "foo1", "foo2", "foo3"
- "foo1" -> "foo1", "foo2", "foo3", "foo4"
- "foo42" -> "foo42", "foo43", "foo44", "foo45"

This resolves the reported issue where branches were getting names like
foo1, foo11, foo111 instead of proper incremental numbering.

Co-Authored-By: sketch <hello@sketch.dev>
Change-ID: sfba5fdcdaf99fdcdk

loop: simplify parseBranchNameAndNumber with regex

Replace verbose manual parsing logic with a clean regular expression
approach to extract trailing digits from branch names.

Changes:
- Replace 20+ lines of manual digit scanning with simple regex: ^(.+?)(\d+)$
- Add regexp import to support the regex functionality
- Maintain exact same behavior and test coverage
- Cleaner, more readable, and less error-prone implementation

The regex ^(.+?)(\d+)$ captures:
- Group 1: Everything up to the trailing digits (non-greedy match)
- Group 2: The trailing digit sequence

This handles all the same cases but with much simpler code.

Co-Authored-By: sketch <hello@sketch.dev>
Change-ID: sea27e90c492b83d8k
2 files changed
tree: ba24ce303cea4aac8e2a63ca0805c42e04f93efb
  1. .github/
  2. .vscode/
  3. bin/
  4. browser/
  5. claudetool/
  6. cmd/
  7. dockerimg/
  8. experiment/
  9. git_tools/
  10. httprr/
  11. llm/
  12. loop/
  13. skabandclient/
  14. skribe/
  15. termui/
  16. test/
  17. webui/
  18. .clabot
  19. .dockerignore
  20. .gitignore
  21. CONTRIBUTING.md
  22. dear_llm.md
  23. go.mod
  24. go.sum
  25. LICENSE
  26. README.md
README.md

Sketch

Go Reference Discord GitHub Workflow Status License

Sketch is an agentic coding tool. It draws the 🦉

🚀 Overview

Sketch runs in your terminal, has a web UI, understands your code, and helps you get work done. To keep your environment pristine, sketch starts a docker container and outputs its work onto a branch in your host git repository.

Sketch helps with most programming environments, but Sketch has extra goodies for Go.

📋 Quick Start

go install sketch.dev/cmd/sketch@latest
sketch

🔧 Requirements

Currently, Sketch runs on macOS and Linux. It uses Docker for containers.

PlatformInstallation
macOSbrew install colima (or Docker Desktop/Orbstack)
Linuxapt install docker.io (or equivalent for your distro)
WSL2Install Docker Desktop for Windows (docker entirely inside WSL2 is tricky)

The sketch.dev service is used to provide access to an LLM service and give you a way to access the web UI from anywhere.

🤝 Community & Feedback

📖 User Guide

Getting Started

Start Sketch by running sketch in a Git repository. It will open your browser to the Sketch chat interface, but you can also use the CLI interface. Use -open=false if you want to use just the CLI interface.

Ask Sketch about your codebase or ask it to implement a feature. It may take a little while for Sketch to do its work, so hit the bell (🔔) icon to enable browser notifications. We won't spam you or anything; it will notify you when the Sketch agent's turn is done, and there's something to look at.

How Sketch Works

When you start Sketch, it:

  1. Creates a Dockerfile
  2. Builds it
  3. Copies your repository into it
  4. Starts a Docker container with the "inside" Sketch running

This design lets you run multiple sketches in parallel since they each have their own sandbox. It also lets Sketch work without worry: it can trash its own container, but it can't trash your machine.

Sketch's agentic loop uses tool calls (mostly shell commands, but also a handful of other important tools) to allow the LLM to interact with your codebase.

Getting Your Git Changes Out

Sketch is trained to make Git commits. When those happen, they are automatically pushed to the git repository where you started sketch with branch names sketch/*.

Finding Sketch branches:

git branch -a --sort=creatordate | grep sketch/ | tail

The UI keeps track of the latest branch it pushed and displays it prominently. You can use standard Git workflows to pull those branches into your workspace:

git cherry-pick $(git merge-base origin/main sketch/foo)

or merge the branch

git merge sketch/foo

or reset to the branch

git reset --hard sketch/foo

Ie use the same workflows you would if you were pulling in a friend's Pull Request.

Advanced: You can ask Sketch to git fetch sketch-host and rebase onto another commit. This will also fetch where you started Sketch, and we do a bit of "git fetch refspec configuration" to make origin/main work as a git reference.

Don't be afraid of asking Sketch to help you rebase, merge/squash commits, rewrite commit messages, and so forth; it's good at it!

Reviewing Diffs

The diff view shows you changes since Sketch started. Leaving comments on lines adds them to the chat box, and, when you hit Send (at the bottom of the page), Sketch goes to work addressing your comments.

Connecting to Sketch's Container

You can interact directly with the container in three ways:

  1. Web UI Terminal: Use the "Terminal" tab in the UI
  2. SSH: Look at the startup logs or click the information icon to see a command like ssh sketch-ilik-eske-tcha-lott. We have automatically configured your SSH configuration to make these special hostnames work.
  3. Visual Studio Code: Look for a command line or magic link behind the information icon, or when Sketch starts up. This starts a new VSCode session "remoted into" the container. You can edit the code, use the terminal, review diffs, and so forth.

Using SSH (and/or VSCode) allows you to forward ports from the container to your machine. For example, if you want to start your development webserver, you can do something like this:

# Forward container port 8888 to local port 8000
ssh -L8000:localhost:8888 sketch-ilik-epor-tfor-ward go run ./cmd/server

This makes http://localhost:8000/ on your machine point to localhost:8888 inside the container.

Using Browser Tools

You can ask Sketch to browse a web page and take screenshots. There are tools both for taking screenshots and "reading images", the latter of which sends the image to the LLM. This functionality is handy if you're working on a web page and want to see what the in-progress change looks like.

❓ FAQ

"No space left on device"

Docker images, containers, and so forth tend to pile up. Ask Docker to prune unused images and containers:

docker system prune -a

🛠️ Development

Go Reference

See CONTRIBUTING.md for development guidelines.

📄 Open Source

Sketch is open source. It is right here in this repository! Have a look around and mod away.

If you want to run Sketch entirely without the sketch.dev service, you can set the flag -skaband-addr="" and then provide an ANTHROPIC_API_KEY environment variable. (More LLM services coming soon!)