Getting the source

The official copy of this repository is located on Use git clone to create a local copy.

Before Contributing


Before we can use your code, you must sign the Google Individual Contributor License Agreement (CLA), which you can do online. The CLA is necessary mainly because you own the copyright to your changes, even after your contribution becomes part of our codebase, so we need your permission to use and distribute your code. We also need to be sure of various other things -- for instance that you‘ll tell us if you know that your code infringes on other people’s patents.


Before you start working on a larger contribution, you should get in touch with us first through the chromium-hterm mailing list with your idea so that we can help out and possibly guide you. Coordinating up front makes it much easier to avoid frustration later on.

Coding Style

We follow the Chromium style guide (which in turn follows the Google style guide). You might find code in the tree that doesn‘t follow those, but it’s most likely due to lack of tools automatically checking and enforcing rather than being done on purpose.

  • Do not one-line if statements.
  • When wrapping function arguments, wrap them all, or keep them aligned.

Automatic Formatting

If you want to see suggestions for how to format your code, you can use the clang-format tool. Note that clang-format can sometimes reformat code that is acceptable according to the style guide, and it cannot catch everything! Make sure to use your best judgment when going through its proposed changes.

# Write the formatted output to stdout.
$ clang-format -style=file foo.js

# Update the file in-place.
$ clang-format -i -style=file foo.js


You can use eslint to quickly check code, or closure compiler.

The bin/ helper script will run both for you.

The .eslintrc.js is copied from the Chromium project.

Console Logging

The console.log functions have a variety of function signatures. We like to stick to a few forms though.

  • A single string when we expect everything to be strings:

    console.log('The field "' + name + '" is invalid: ' + val);
  • A string followed by objects when dealing with more than strings, and we want to be able to easily explore the object in the debugging console:

    console.log('The field "' + name + '" is invalid:', val);
  • Or you can use ES6 template literals/strings:

    console.log(`The field "${name}" is invalid: ${val}`);
    console.log(`The field "${name}" is invalid:`, val);

Submitting patches

This repository only accepts commits that are submitted through “Gerrit”, the code-review software. In order to submit a patch through Gerrit, you'll need to do a one-time setup to get things ready.

  1. Create an account on (You can use OAuth for this, no need for yet-another-password.)

  2. From the root of your libapps/ repo, run the command:

     $ curl -Lo `git rev-parse --git-dir`/hooks/commit-msg ; chmod +x `git rev-parse --git-dir`/hooks/commit-msg

    This will copy a commit-msg hook necessary for Gerrit. The hook annotates your commit messages with Change-Id‘s. It’s important to leave these intact, as it's how commits are mapped to code reviews.

Now you're free to start working. Create a branch to hold your changes...

$ git checkout -b hterm_stuff

Then start hacking and commit your changes. When you're ready to submit, push with...

$ git push origin HEAD:refs/for/master

This will push the current branch to Gerrit for review. Once the change has passed review it will be cherry-picked onto the master branch of the official repository.

The output of this command should include a url to Gerrit web page for the review. Add one or more reviewers using the “Add Reviewer” button on that web page.

If the official repository changes, you can fetch the new commits using...

# This command only affects your local repository files, you can run it
# regardless of which branch you're currently on.
$ git fetch

And then re-base any branches with work-in-progress.

$ git checkout hterm_stuff
$ git rebase origin/master

Sometimes this rebase will fail due to merge conflicts which will have to be resolved by hand.