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Please note! Please make sure you have installed Git and Node.js before building. What's more, We recommend that you use Linux rather than Windows for configuration

Import to your existing React application

yarn install clipcc-gui@latest


yarn install

Edit/play by your self

git clone
cd clipcc-gui
yarn install
yarn start

Then go to http://localhost:8601/ - the playground outputs the default GUI component.

If you want to edit clipcc-vm, clipcc-block or more, you can use yarn link

# Please clone the repo you need in your work directory first.
cd clipcc-vm && yarn && yarn link
cd clipcc-block && yarn
# Build the clipcc-block and link it, Python 3 required.
yarn build
yarn link
# ...
cd clipcc-gui
yarn link clipcc-vm clipcc-block
yarn start

Only clipcc-vm and clipcc-gui supports hot-reload.

If you need to import clipcc-gui to other projects by yarn link, You need to execute yarn build:dist first.

You can also use Yarn Workspace, see here.

What's different from the original Scratch

  1. clipcc-gui uses React 17.0.2 instead of React 16.2
  2. clipcc-block rewrites the build script using Python 3, which allows it to run properly on Windows.
  3. We use Yarn.



You may want to review the documentation for Jest and Enzyme as you write your tests.

See jest cli docs for more options.

Running tests

NOTE: If you're a Windows user, please run these scripts in Windows cmd.exe instead of Git Bash/MINGW64.

Before running any test, make sure you have run yarn install from this (clipcc-gui) repository's top level.

Main testing command

To run linter, unit tests, build, and integration tests, all at once:

yarn test

Running unit tests

To run unit tests in isolation:

yarn run test:unit

To run unit tests in watch mode (watches for code changes and continuously runs tests):

yarn run test:unit -- --watch

You can run a single file of integration tests (in this example, the button tests):

$(yarn bin)/jest --runInBand test/unit/components/button.test.jsx

Running integration tests

Integration tests use a headless browser to manipulate the actual HTML and javascript that the repo produces. You will not see this activity (though you can hear it when sounds are played!).

Note that integration tests require you to first create a build that can be loaded in a browser:

yarn run build

Then, you can run all integration tests:

yarn run test:integration

Or, you can run a single file of integration tests (in this example, the backpack tests):

$(yarn bin)/jest --runInBand test/integration/backpack.test.js

If you want to watch the browser as it runs the test, rather than running headless, use:

USE_HEADLESS=no $(yarn bin)/jest --runInBand test/integration/backpack.test.js


Ignoring optional dependencies

When running yarn install, you can get warnings about optionsl dependencies:

npm WARN optional Skipping failed optional dependency /chokidar/fsevents:
npm WARN notsup Not compatible with your operating system or architecture: fsevents@1.2.7

You can suppress them by adding the no-optional switch:

yarn install --no-optional

Further reading: Stack Overflow

Resolving dependencies

When installing for the first time, you can get warnings that need to be resolved:

npm WARN eslint-config-scratch@5.0.0 requires a peer of babel-eslint@^8.0.1 but none was installed.
npm WARN eslint-config-scratch@5.0.0 requires a peer of eslint@^4.0 but none was installed.
npm WARN scratch-paint@0.2.0-prerelease.20190318170811 requires a peer of react-intl-redux@^0.7 but none was installed.
npm WARN scratch-paint@0.2.0-prerelease.20190318170811 requires a peer of react-responsive@^4 but none was installed.

You can check which versions are available:

yarn view react-intl-redux@0.* version

You will need to install the required version:

yarn install  --no-optional --save-dev react-intl-redux@^0.7

The dependency itself might have more missing dependencies, which will show up like this:

user@machine:~/sources/scratch/clipcc-gui (491-translatable-library-objects)$ yarn install  --no-optional --save-dev react-intl-redux@^0.7
clipcc-gui@0.1.0 /media/cuideigin/Linux/sources/scratch/clipcc-gui
├── react-intl-redux@0.7.0
└── UNMET PEER DEPENDENCY react-responsive@5.0.0

You will need to install those as well:

yarn install  --no-optional --save-dev react-responsive@^5.0.0

Further reading: Stack Overflow


These are names for the action which causes a state change. Some examples are:


How transitions relate to loading states

Like this diagram of the project state machine shows, various transition actions can move us from one loading state to another:

Project state diagram

Note: for clarity, the diagram above excludes states and transitions relating to error handling.