less-plugin-dls

Less plugin for Baidu DLS.

Installation

npm i --save-dev less-plugin-dls

Usage

Autoinject with Less plugin

import less from 'less'
import dls from 'less-plugin-dls'

less
  .render('a { color: @dls-link-font-color-normal; }', {
    plugins: [dls()]
  })
  .then(result => {
    // handle result
  })

Import from stylesheets

With less-loader:

@import "~less-plugin-dls/tokens/index.less";

a {
  color: @dls-link-font-color-normal;
}

Use CLI argument

lessc style.less --dls

Using metadata

Variable values/metadata are provided in three formats for each theme.

File	Description
variables.js	The raw variable values in JavaScript ESM format. Token names are transformed from @dls-color-brand-7 to dlsColorBrand7 as named exports.
variables.json	The raw variable values in JSON format.
variables.less	The variable values in Less format.

// types for the JSON format:
interface Variables {
  [tokenName: string]: {
    value: string
    type: 'color' | 'font' | 'numeric' | 'length' | 'complex'
    global: boolean
  }
}

We also included a set of metadata files for different themes and scopes. Currently the only supported theme is ai and supported scopes are global and palette. The dist file names are in the format of variables.<scope>.<theme>.<format>, where <scope> and <theme> are both optional. eg.

variables.global.less # global variables, w/o component variables
variables.palette.ai.less # global color palette variables in AI theme

Custom functions

dls-contextual(@color, @type)

To generate contextual colors according to the given brand color.

Params:

• @color: Color - the brand color.
• @type: info | success | warning | error - the color context.

Return value:

Color - the generated contextual color.

@color: dls-contextual(#0052cc, success); // → #39bf45

dls-shade(@color, @level)

To generate a specific shade level of the given base color.

Params:

• @color: Color - the base color.
• @level: Number - the shade level.

Return value:

Color - the generated shaded color.

@color: dls-shade(#3d88f2, 3); // → #b3cfff

dls-sum(...@dimensions)

To get the sum of the given dimensions or calc expressions.

Params:

• @dimensions: List<Dimension | Calc> - A list of length values.

Return value:

Dimension | Calc - the total value of the given list.

@width: dls-sum(1px, 30%); // → calc(1px + 30%)
@height: dls-sum(1px, 10px, 100px); // → 111px
@top: dls-sum(calc(1px + 5em), -1px); // → 5em
@left: dls-sum(calc(1px + 5em), -1px, calc(-5em)); // → 0

dls-even(@dimension)

To calculate the closest even integer value for a given dimension.

Params:

• @dimension: Dimension - The given length value.

Return value:

Dimension - the closest even value.

@width: dls-even(1px); // → 2px
@height: dls-even(2); // → 2
@top: dls-even(19.6px); // → 20px
@left: dls-even(2.8em); // → 2em

dls-line-height(@line-height, @font-size): Dimension

To calculate the absolute line-height from the given line-height and font-size value.

Will return @line-height directly if it is an absolute length (eg. 15px, 2em). Will return the product of @line-height and @font-size for relative lengths (eg. 1.5, 200%).

Params:

• @line-height: Dimension - the line-height value.
• @font-size: Dimension - the font-size value.

Return value:

The absolute length of the line-height.

@h1: dls-line-height(1.5, 16px); // → 24px
@h2: dls-line-height(120%, 15px); // → 18px
@h3: dls-line-height(2em, 1.2em); // → 2em

Options

theme: 'ai' | undefined

The theme of the DLS. If not specified, the default theme will be used.

reduceCalc: boolean

Indicates whether to reduce calc expression to the simplest form or not.

Default value: true.

Tooling

CLI checker

npx dls check -c -o result.log

Commands

check

To check which variables are not used inside a directory. The current strategy is plain text search so that doesn't cover the case of Less's variable name interpolation.

Options

• --dir / -d

  The target directory to check.

  Default: ..

• --exclude / -x

  Comma-separated glob expression, indicates which files should be ignored.

  Default: node_modules,test.

  npx dls check -x node_modules,test,dist # or --exclude=node_modules,test,dist

• --components / -c

  Comma-separated component names to specify which component-level variables will be checked. --components=all will check all component-level variables.

  Variables can be ignored if you put a .dlsignore file under the project root directory, with each variable (should be prefixed by @) on a single line. Lines led by # will be treated as comments.

  npx dls check -c button,select # or --components=button,select
  npx dls check -c all # or --components=all

• --output / -o

  The output file for the check result.

  npx dls check -o result.log # or --output=result.log

Editor Extensions

• Baidu DLS (VS Code)

  Marketplace / GitHub

License

MIT