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diff --git a/doc/development/fe_guide/style_guide_js.md b/doc/development/fe_guide/style_guide_js.md
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--- a/doc/development/fe_guide/style_guide_js.md
+++ b/doc/development/fe_guide/style_guide_js.md
@@ -11,207 +11,223 @@ See [our current .eslintrc][eslintrc] for specific rules and patterns.
#### ESlint
-- **Never** disable eslint rules unless you have a good reason. You may see a lot of legacy files with `/* eslint-disable some-rule, some-other-rule */` at the top, but legacy files are a special case. Any time you develop a new feature or refactor an existing one, you should abide by the eslint rules.
-
-- **Never Ever EVER** disable eslint globally for a file
+1. **Never** disable eslint rules unless you have a good reason.
+You may see a lot of legacy files with `/* eslint-disable some-rule, some-other-rule */`
+at the top, but legacy files are a special case. Any time you develop a new feature or
+refactor an existing one, you should abide by the eslint rules.
+1. **Never Ever EVER** disable eslint globally for a file
```javascript
- // bad
- /* eslint-disable */
+ // bad
+ /* eslint-disable */
- // better
- /* eslint-disable some-rule, some-other-rule */
+ // better
+ /* eslint-disable some-rule, some-other-rule */
- // best
- // nothing :)
+ // best
+ // nothing :)
```
-- If you do need to disable a rule for a single violation, try to do it as locally as possible
-
+1. If you do need to disable a rule for a single violation, try to do it as locally as possible
```javascript
- // bad
- /* eslint-disable no-new */
+ // bad
+ /* eslint-disable no-new */
- import Foo from 'foo';
+ import Foo from 'foo';
- new Foo();
+ new Foo();
- // better
- import Foo from 'foo';
+ // better
+ import Foo from 'foo';
- // eslint-disable-next-line no-new
- new Foo();
+ // eslint-disable-next-line no-new
+ new Foo();
```
+1. There are few rules that we need to disable due to technical debt. Which are:
+ 1. [no-new][eslint-new]
+ 1. [class-methods-use-this][eslint-this]
-- When they are needed _always_ place ESlint directive comment blocks on the first line of a script, followed by any global declarations, then a blank newline prior to any imports or code.
-
+1. When they are needed _always_ place ESlint directive comment blocks on the first line of a script,
+followed by any global declarations, then a blank newline prior to any imports or code.
```javascript
- // bad
- /* global Foo */
- /* eslint-disable no-new */
- import Bar from './bar';
+ // bad
+ /* global Foo */
+ /* eslint-disable no-new */
+ import Bar from './bar';
- // good
- /* eslint-disable no-new */
- /* global Foo */
+ // good
+ /* eslint-disable no-new */
+ /* global Foo */
- import Bar from './bar';
+ import Bar from './bar';
```
-- **Never** disable the `no-undef` rule. Declare globals with `/* global Foo */` instead.
-
-- When declaring multiple globals, always use one `/* global [name] */` line per variable.
+1. **Never** disable the `no-undef` rule. Declare globals with `/* global Foo */` instead.
+1. When declaring multiple globals, always use one `/* global [name] */` line per variable.
```javascript
- // bad
- /* globals Flash, Cookies, jQuery */
+ // bad
+ /* globals Flash, Cookies, jQuery */
- // good
- /* global Flash */
- /* global Cookies */
- /* global jQuery */
+ // good
+ /* global Flash */
+ /* global Cookies */
+ /* global jQuery */
```
-
-- Use up to 3 parameters for a function or class. If you need more accept an Object instead.
+1. Use up to 3 parameters for a function or class. If you need more accept an Object instead.
```javascript
- // bad
- fn(p1, p2, p3, p4) {}
+ // bad
+ fn(p1, p2, p3, p4) {}
- // good
- fn(options) {}
+ // good
+ fn(options) {}
```
#### Modules, Imports, and Exports
-- Use ES module syntax to import modules
-
+1. Use ES module syntax to import modules
```javascript
- // bad
- require('foo');
+ // bad
+ require('foo');
- // good
- import Foo from 'foo';
+ // good
+ import Foo from 'foo';
- // bad
- module.exports = Foo;
+ // bad
+ module.exports = Foo;
- // good
- export default Foo;
+ // good
+ export default Foo;
```
-- Relative paths
+1. Relative paths: when importing a module in the same directory, a child
+directory, or an immediate parent directory prefer relative paths. When
+importing a module which is two or more levels up, prefer either `~/` or `ee/`
+.
- Unless you are writing a test, always reference other scripts using relative paths instead of `~`
+In **app/assets/javascripts/my-feature/subdir**:
- In **app/assets/javascripts**:
- ```javascript
- // bad
- import Foo from '~/foo'
+``` javascript
+// bad
+import Foo from '~/my-feature/foo';
+import Bar from '~/my-feature/subdir/bar';
+import Bin from '~/my-feature/subdir/lib/bin';
- // good
- import Foo from '../foo';
- ```
+// good
+import Foo from '../foo';
+import Bar from './bar';
+import Bin from './lib/bin';
+```
- In **spec/javascripts**:
- ```javascript
- // bad
- import Foo from '../../app/assets/javascripts/foo'
+In **spec/javascripts**:
- // good
- import Foo from '~/foo';
- ```
+``` javascript
+// bad
+import Foo from '../../app/assets/javascripts/my-feature/foo';
+
+// good
+import Foo from '~/my-feature/foo';
+```
-- Avoid using IIFE. Although we have a lot of examples of files which wrap their contents in IIFEs (immediately-invoked function expressions), this is no longer necessary after the transition from Sprockets to webpack. Do not use them anymore and feel free to remove them when refactoring legacy code.
+When referencing an **EE component**:
-- Avoid adding to the global namespace.
+``` javascript
+// bad
+import Foo from '../../../../../ee/app/assets/javascripts/my-feature/ee-foo';
+// good
+import Foo from 'ee/my-feature/foo';
+```
+
+1. Avoid using IIFE. Although we have a lot of examples of files which wrap their
+contents in IIFEs (immediately-invoked function expressions),
+this is no longer necessary after the transition from Sprockets to webpack.
+Do not use them anymore and feel free to remove them when refactoring legacy code.
+
+1. Avoid adding to the global namespace.
```javascript
- // bad
- window.MyClass = class { /* ... */ };
+ // bad
+ window.MyClass = class { /* ... */ };
- // good
- export default class MyClass { /* ... */ }
+ // good
+ export default class MyClass { /* ... */ }
```
-- Side effects are forbidden in any script which contains exports
-
+1. Side effects are forbidden in any script which contains exports
```javascript
- // bad
- export default class MyClass { /* ... */ }
+ // bad
+ export default class MyClass { /* ... */ }
- document.addEventListener("DOMContentLoaded", function(event) {
- new MyClass();
- }
+ document.addEventListener("DOMContentLoaded", function(event) {
+ new MyClass();
+ }
```
#### Data Mutation and Pure functions
-- Strive to write many small pure functions, and minimize where mutations occur.
-
+1. Strive to write many small pure functions, and minimize where mutations occur.
```javascript
- // bad
- const values = {foo: 1};
+ // bad
+ const values = {foo: 1};
- function impureFunction(items) {
- const bar = 1;
+ function impureFunction(items) {
+ const bar = 1;
- items.foo = items.a * bar + 2;
+ items.foo = items.a * bar + 2;
- return items.a;
- }
+ return items.a;
+ }
- const c = impureFunction(values);
+ const c = impureFunction(values);
- // good
- var values = {foo: 1};
+ // good
+ var values = {foo: 1};
- function pureFunction (foo) {
- var bar = 1;
+ function pureFunction (foo) {
+ var bar = 1;
- foo = foo * bar + 2;
+ foo = foo * bar + 2;
- return foo;
- }
+ return foo;
+ }
- var c = pureFunction(values.foo);
+ var c = pureFunction(values.foo);
```
-- Avoid constructors with side-effects
+1. Avoid constructors with side-effects
-- Prefer `.map`, `.reduce` or `.filter` over `.forEach`
+1. Prefer `.map`, `.reduce` or `.filter` over `.forEach`
A forEach will cause side effects, it will be mutating the array being iterated. Prefer using `.map`,
`.reduce` or `.filter`
-
```javascript
- const users = [ { name: 'Foo' }, { name: 'Bar' } ];
+ const users = [ { name: 'Foo' }, { name: 'Bar' } ];
- // bad
- users.forEach((user, index) => {
- user.id = index;
- });
+ // bad
+ users.forEach((user, index) => {
+ user.id = index;
+ });
- // good
- const usersWithId = users.map((user, index) => {
- return Object.assign({}, user, { id: index });
- });
+ // good
+ const usersWithId = users.map((user, index) => {
+ return Object.assign({}, user, { id: index });
+ });
```
#### Parse Strings into Numbers
-- `parseInt()` is preferable over `Number()` or `+`
-
+1. `parseInt()` is preferable over `Number()` or `+`
```javascript
- // bad
- +'10' // 10
+ // bad
+ +'10' // 10
- // good
- Number('10') // 10
+ // good
+ Number('10') // 10
- // better
- parseInt('10', 10);
+ // better
+ parseInt('10', 10);
```
#### CSS classes used for JavaScript
-- If the class is being used in Javascript it needs to be prepend with `js-`
+1. If the class is being used in Javascript it needs to be prepend with `js-`
```html
// bad
<button class="add-user">
@@ -226,238 +242,298 @@ A forEach will cause side effects, it will be mutating the array being iterated.
### Vue.js
-
#### Basic Rules
-- Only include one Vue.js component per file.
-- Export components as plain objects:
-
+1. The service has it's own file
+1. The store has it's own file
+1. Use a function in the bundle file to instantiate the Vue component:
```javascript
- export default {
- template: `<h1>I'm a component</h1>
- }
- ```
+ // bad
+ class {
+ init() {
+ new Component({})
+ }
+ }
-#### Naming
-- **Extensions**: Use `.vue` extension for Vue components.
-- **Reference Naming**: Use PascalCase for Vue components and camelCase for their instances:
+ // good
+ document.addEventListener('DOMContentLoaded', () => new Vue({
+ el: '#element',
+ components: {
+ componentName
+ },
+ render: createElement => createElement('component-name'),
+ }));
+ ```
+1. Don not use a singleton for the service or the store
```javascript
- // bad
- import cardBoard from 'cardBoard';
+ // bad
+ class Store {
+ constructor() {
+ if (!this.prototype.singleton) {
+ // do something
+ }
+ }
+ }
- // good
- import CardBoard from 'cardBoard'
+ // good
+ class Store {
+ constructor() {
+ // do something
+ }
+ }
+ ```
- // bad
- components: {
- CardBoard: CardBoard
- };
+#### Naming
+1. **Extensions**: Use `.vue` extension for Vue components.
+1. **Reference Naming**: Use camelCase for their instances:
+ ```javascript
+ // good
+ import cardBoard from 'cardBoard'
- // good
- components: {
- cardBoard: CardBoard
- };
+ components: {
+ cardBoard:
+ };
```
-- **Props Naming:**
-- Avoid using DOM component prop names.
-- Use kebab-case instead of camelCase to provide props in templates.
-
+1. **Props Naming:** Avoid using DOM component prop names.
+1. **Props Naming:** Use kebab-case instead of camelCase to provide props in templates.
```javascript
- // bad
- <component class="btn">
+ // bad
+ <component class="btn">
- // good
- <component css-class="btn">
+ // good
+ <component css-class="btn">
- // bad
- <component myProp="prop" />
+ // bad
+ <component myProp="prop" />
- // good
- <component my-prop="prop" />
-```
+ // good
+ <component my-prop="prop" />
+ ```
#### Alignment
-- Follow these alignment styles for the template method:
-
+1. Follow these alignment styles for the template method:
```javascript
- // bad
- <component v-if="bar"
- param="baz" />
+ // bad
+ <component v-if="bar"
+ param="baz" />
- <button class="btn">Click me</button>
+ <button class="btn">Click me</button>
- // good
- <component
- v-if="bar"
- param="baz"
- />
+ // good
+ <component
+ v-if="bar"
+ param="baz"
+ />
- <button class="btn">
- Click me
- </button>
+ <button class="btn">
+ Click me
+ </button>
- // if props fit in one line then keep it on the same line
- <component bar="bar" />
+ // if props fit in one line then keep it on the same line
+ <component bar="bar" />
```
#### Quotes
-- Always use double quotes `"` inside templates and single quotes `'` for all other JS.
-
+1. Always use double quotes `"` inside templates and single quotes `'` for all other JS.
```javascript
- // bad
- template: `
- <button :class='style'>Button</button>
- `
-
- // good
- template: `
- <button :class="style">Button</button>
- `
+ // bad
+ template: `
+ <button :class='style'>Button</button>
+ `
+
+ // good
+ template: `
+ <button :class="style">Button</button>
+ `
```
#### Props
-- Props should be declared as an object
-
+1. Props should be declared as an object
```javascript
- // bad
- props: ['foo']
-
- // good
- props: {
- foo: {
- type: String,
- required: false,
- default: 'bar'
+ // bad
+ props: ['foo']
+
+ // good
+ props: {
+ foo: {
+ type: String,
+ required: false,
+ default: 'bar'
+ }
}
- }
```
-- Required key should always be provided when declaring a prop
-
+1. Required key should always be provided when declaring a prop
```javascript
- // bad
- props: {
- foo: {
- type: String,
+ // bad
+ props: {
+ foo: {
+ type: String,
+ }
}
- }
-
- // good
- props: {
- foo: {
- type: String,
- required: false,
- default: 'bar'
+
+ // good
+ props: {
+ foo: {
+ type: String,
+ required: false,
+ default: 'bar'
+ }
}
- }
```
-- Default key should always be provided if the prop is not required:
-
+1. Default key should always be provided if the prop is not required:
```javascript
- // bad
- props: {
- foo: {
- type: String,
- required: false,
+ // bad
+ props: {
+ foo: {
+ type: String,
+ required: false,
+ }
}
- }
-
- // good
- props: {
- foo: {
- type: String,
- required: false,
- default: 'bar'
+
+ // good
+ props: {
+ foo: {
+ type: String,
+ required: false,
+ default: 'bar'
+ }
}
- }
- // good
- props: {
- foo: {
- type: String,
- required: true
+ // good
+ props: {
+ foo: {
+ type: String,
+ required: true
+ }
}
- }
```
#### Data
-- `data` method should always be a function
+1. `data` method should always be a function
```javascript
- // bad
- data: {
- foo: 'foo'
- }
-
- // good
- data() {
- return {
+ // bad
+ data: {
foo: 'foo'
- };
- }
+ }
+
+ // good
+ data() {
+ return {
+ foo: 'foo'
+ };
+ }
```
#### Directives
-- Shorthand `@` is preferable over `v-on`
-
+1. Shorthand `@` is preferable over `v-on`
```javascript
- // bad
- <component v-on:click="eventHandler"/>
+ // bad
+ <component v-on:click="eventHandler"/>
- // good
- <component @click="eventHandler"/>
+ // good
+ <component @click="eventHandler"/>
```
-- Shorthand `:` is preferable over `v-bind`
-
+1. Shorthand `:` is preferable over `v-bind`
```javascript
- // bad
- <component v-bind:class="btn"/>
+ // bad
+ <component v-bind:class="btn"/>
- // good
- <component :class="btn"/>
+ // good
+ <component :class="btn"/>
```
#### Closing tags
-- Prefer self closing component tags
-
+1. Prefer self closing component tags
```javascript
- // bad
- <component></component>
+ // bad
+ <component></component>
- // good
- <component />
+ // good
+ <component />
```
#### Ordering
-- Order for a Vue Component:
+1. Order for a Vue Component:
1. `name`
- 2. `props`
- 3. `data`
- 4. `components`
- 5. `computedProps`
- 6. `methods`
- 7. lifecycle methods
- 1. `beforeCreate`
- 2. `created`
- 3. `beforeMount`
- 4. `mounted`
- 5. `beforeUpdate`
- 6. `updated`
- 7. `activated`
- 8. `deactivated`
- 9. `beforeDestroy`
- 10. `destroyed`
- 8. `template`
+ 1. `props`
+ 1. `mixins`
+ 1. `directives`
+ 1. `data`
+ 1. `components`
+ 1. `computedProps`
+ 1. `methods`
+ 1. `beforeCreate`
+ 1. `created`
+ 1. `beforeMount`
+ 1. `mounted`
+ 1. `beforeUpdate`
+ 1. `updated`
+ 1. `activated`
+ 1. `deactivated`
+ 1. `beforeDestroy`
+ 1. `destroyed`
+
+#### Vue and Boostrap
+1. Tooltips: Do not rely on `has-tooltip` class name for Vue components
+ ```javascript
+ // bad
+ <span
+ class="has-tooltip"
+ title="Some tooltip text">
+ Text
+ </span>
+
+ // good
+ <span
+ v-tooltip
+ title="Some tooltip text">
+ Text
+ </span>
+ ```
+
+1. Tooltips: When using a tooltip, include the tooltip directive, `./app/assets/javascripts/vue_shared/directives/tooltip.js`
+
+1. Don't change `data-original-title`.
+ ```javascript
+ // bad
+ <span data-original-title="tooltip text">Foo</span>
+
+ // good
+ <span title="tooltip text">Foo</span>
+
+ $('span').tooltip('fixTitle');
+ ```
+### The Javascript/Vue Accord
+The goal of this accord is to make sure we are all on the same page.
+
+1. When writing Vue, you may not use jQuery in your application.
+1.1 If you need to grab data from the DOM, you may query the DOM 1 time while bootstrapping your application to grab data attributes using `dataset`. You can do this without jQuery.
+1.2 You may use a jQuery dependency in Vue.js following [this example from the docs](https://vuejs.org/v2/examples/select2.html).
+1.3 If an outside jQuery Event needs to be listen to inside the Vue application, you may use jQuery event listeners.
+1.4 We will avoid adding new jQuery events when they are not required. Instead of adding new jQuery events take a look at [different methods to do the same task](https://vuejs.org/v2/api/#vm-emit).
+
+1. You may query the `window` object 1 time, while bootstrapping your application for application specific data (e.g. `scrollTo` is ok to access anytime). Do this access during the bootstrapping of your application.
+
+1. You may have a temporary but immediate need to create technical debt by writing code that does not follow our standards, to be refactored later. Maintainers need to be ok with the tech debt in the first place. An issue should be created for that tech debt to evaluate it further and discuss. In the coming months you should fix that tech debt, with it's priority to be determined by maintainers.
+
+1. When creating tech debt you must write the tests for that code before hand and those tests may not be rewritten. e.g. jQuery tests rewritten to Vue tests.
+
+1. You may choose to use VueX as a centralized state management. If you choose not to use VueX, you must use the *store pattern* which can be found in the [Vue.js documentation](https://vuejs.org/v2/guide/state-management.html#Simple-State-Management-from-Scratch).
+1. Once you have chosen a centralized state management solution you must use it for your entire application. i.e. Don't mix and match your state management solutions.
## SCSS
- [SCSS](style_guide_scss.md)
[airbnb-js-style-guide]: https://github.com/airbnb/javascript
[eslintrc]: https://gitlab.com/gitlab-org/gitlab-ce/blob/master/.eslintrc
+[eslint-this]: http://eslint.org/docs/rules/class-methods-use-this
+[eslint-new]: http://eslint.org/docs/rules/no-new
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