Contributing to Omni Components
Welcome! We encourage contributions and here's a few important guidelines we would like you to follow:
Code of Conduct
Please read and follow our Code of Conduct.
Issues
Engagement always starts with an Issue where conversations and debates can occur around bugs and feature requests:
- Do search for a similar / existing Issue prior to submitting a new one.
- Do not use issues for any personal support. Use Discussions or StackOverflow instead.
- Do not side-track or derail issues threads. Stick to the topic please.
- Do not post comments using just "+1", "++" or "👍". Use Reactions instead.
Bugs
A bug is an error, flaw or fault associated with any part of the project:
- Do search for a similar / existing Issue prior to submitting a new one.
- Do describe the bug concisely, avoid adding extraneous code, logs or screenshots.
- Do attach a minimal test or repro (e.g. CodePen, jsFiddle) to demonstrate the bug.
Feature Requests
A feature request is an improvement or new capability associated with any part of the project:
- Do search for a similar / existing Issue prior to submitting a new one.
- Do provide sufficient motivation / use case(s) for the feature.
- Do not submit multiple unrelated requests within one request.
💡 TIP: We suggest that you engage as much as possible within an Issue prior to proceeding with any contributions.
Vulnerabilities
A vulnerability is typically a security-related risk associated with any part of the project (or any dependencies):
- Do refer to our Security Policy for more info.
- Do report vulnerabilities via this link.
- Do not report any Issues or mention in public Discussions for discretionary purposes.
Development
Branches
develop
- Default branch for all Pull Requests.main
- Stable branch for all periodic releases.
Getting Started
Dependencies
- Git (v2+)
- Node.js (v16+)
- NPM (v7+)
- VS Code + recommended extensions (recommended, but not required).
Setup
-
Fork the repository and create a new branch from
develop
(Do not directly usedevelop
as this will prevent certain workflows from being triggered). -
Go to the Actions tab and enable workflow runs for the repository. (This is needed to generate screenshots for tests)
-
Add a
PROTECTED_TOKEN
secret for workflow runs with a personal access token as its value. (Optional)- This is to enable re-triggering of workflows when a workflow commits screenshots. If this is not set a new code commit will be required to trigger the next workflow as it uses the default
GITHUB_TOKEN
instead. - See Automatic token authentication for detail.
- This is to enable re-triggering of workflows when a workflow commits screenshots. If this is not set a new code commit will be required to trigger the next workflow as it uses the default
-
Clone the forked repo, checkout your branch, and run
npm ci
inside the repository root. -
Install the testing dependencies with
npx playwright install --with-deps
. -
Start up the dev server with
npm run serve
(or by launching debugging in VS Code).
Directory Structure
When adding or editing components, please note the following key directories:
├── src
│ ├── button
│ │ ├── Button.stories.ts
│ │ ├── Button.spec.ts
│ │ ├── Button.ts
│ │ ├── index.ts
│ │ ├── README.md
│ ├── ...
├── ...
src
- Contains all components in a flat structure, each named after a component, e.g.button
. Contents:Button.stories.ts
- The stories for the component.Button.spec.ts
- The tests for the component.Button.ts
- The component. (NOTE: There might be multiple, depending on complexity and composition)index.ts
- The directory-level index, containing one or more component exports.README.md
- The README for the component (NOTE: Generated when Pull Request is merged).
Naming Conventions
- Do use lower case kebab-case for component folder names, e.g.
some-component
. 🍢 - Do use uppercase first letter CamelCase for component file names, e.g.
SomeComponent.ts
. - Do use the name of the component, suffixed with
.stories
for component story file names, e.g.SomeComponent.stories.ts
. - Do use the name of the component, suffixed with
.spec
for component test file names, e.g.SomeComponent.spec.ts
. - Do match component name with its file name, e.g.
SomeComponent.ts
containsexport class SomeComponent { ... }
. - Do prefix the custom element name with
omni-
. - Do not use any verbs or prefixes within component property names, instead do use nouns, e.g.
mode
,position
. - Do name CSS custom properties as follows:
- Component:
--omni-<component>-<state>-<css-property>
, e.g.--omni-button-primary-background-color
- Theme:
--omni-theme-<state>-<css-property>
, e.g.--omni-theme-primary-color
- Component:
- Do follow standard TypeScript, Lit related conventions.
💡 TIP: Refer to existing components and stories for examples.
Definition of Done
Here's a non-exhaustive list of requirements that are key to contributing to this project.
General
- Do use TypeScript, with common language practices.
- Do follow our naming conventions.
Components
- Do base off OmniElement.
- Do implement "mobile first" templates, leveraging Responsive Design layout and styling principles. 📱
- Do utilize LitElement's decorators, required for element and property names.
- Do ensure sufficient JSDoc as well as general code comments are added.
- Do add an
HTMLElementTagNameMap
entry as documented here. - Do use and extend existing shared CSS component and theme custom properties. (See
src/core/OmniElement.ts
) - Do set suitable CSS custom property defaults, avoid hard-coding CSS property values directly within components, unless deemed required.
- Do adhere to and leverage existing DOM standards when making use of
<input>
element. - Do implement suitable DOM accessibility features.
- Do allow components to be user customizable via slot implementations.
- Do implement only one component class within a component file.
Stories
- Do use Component Story Format (CSF) 3.
- Do set the
data-testid
within every story template. - Do ensure that stories are authored to be both dark and light theme friendly (test via the hosted documentation).
- Do ensure that stories have their respective framework templates authored for each story where required.
Tests
- Do cater for behavioral testing for components that covers interaction and visual testing.
- Test the attributes of the component using assertions.
- Test visual behaviour by interactions. (Ensure mobile rendering differences are catered for)
- Take a screenshot of the initial state of the component.
- Perform interactions with the component.
- Take a screenshot of every change in state during the interactions.
- Test the events of the component using mock functions.
- Do ensure that the test name is unique and descriptive of what will be tested.
- Do ensure that the tests written result in at least 80% code coverage for the component.
- Do ensure that the tests focus on user facing features of the component, not the internal workings of the component.
- Do ensure that all tests pass.
Themes
- Do maintain each built-in theme, by ensuring all
--omni-theme-*
CSS custom properties are implemented. - Do test each theme thoroughly via the hosted documentation.
💡 TIP: Refer to existing components, stories and themes for examples for any of the above.
Testing
Tests are conducted via Playwright.
Running tests from shell
- To run the end-to-end tests for all components on all configured browsers
npm run test
- To only run the end-to-end tests for all components on all configured browsers. (
npm run serve
must be run separately)
npm run test:only
- To run the end-to-end tests for all components only on Chromium. (
npm run serve
must be run separately)
npx playwright test --project=chromium
- To run the tests of a specific component on all configured browsers. (
npm run serve
must be run separately)
npx playwright test Component.spec.ts
Running tests from Playwright Test Explorer within VSCode
- Ensure that
npm run serve
is running separately. - Refer to the Playwright Test Explorer extension.
Viewing the test report
- To view the latest test report.
npm run test-results
🔶 NOTE: Screenshot testing only asserts during CI workflows, the report will locally only show current screenshots taken, but not perform any comparisons.
Pull Requests
Requirements
- Do ensure the branch is up to date with the
develop
branch. - Do ensure there's no conflicts with the
develop
branch. - Do ensure that all automatic checks pass. ✔
Checks
- Code scanning passes.
- Lint validation passes.
💡 TIP: Analyze changes locally with
npm run lint
.
- Format validation passes.
💡 TIP: Apply changes locally with
npm run format
.
- All tests pass.