react-classnaming
v0.16.4TypeScript
Tools to establish CSS classes as an explicit abstraction layer and to handle it as an interface between React and CSSStyleDeclaration
0/weekUpdated 3 years agoMITUnpacked: 45.9 KB
Published by Andrii Kirmas
npm install react-classnamingreact-classnaming
Tools to establish CSS classes as an explicit abstraction layer and to handle it as an interface "a shared boundary across which two or more separate components of a computer system exchange information") between React and CSSStyleDeclaration.
!build@ci !coverage    
  !license
Objectives
1. Use CSS classes as an ontology of front-end project for clean communication between developers and non-tech staff
2. Make CSS classes be an explicit and predictable informational layer
3. Enforce declarative programming paradigm
4. Enforce contract programming (via TypeScript)
Dev features
1. Enforce single source of truth of class appending – treat as TypeScript-driven dedupe
2. Require strict boolean for value of class condition
3. Use IDE type hints as developers' UX for faster issues resolving
4. BEM
5. CSS-modules agnostic
Use package like postcss-plugin-d-ts to prepare strict declaration of CSS
Installation and brief overview
``bash`
npm install --save react-classnaming
`typescriptclassName: string
import {
// Returns function for building from conditioned CSS classes with "context" (if was provided) from props for using only declared CSS classesclassName
classNaming,
// Similar to classNaming, specifies mapping to component's (i.e. 3rd-party) -related props
classNamesMap,
// Identical function for TS restriction on classes determed in CSS and not used in component
classNamesCheck,
// Works with BEM conditional object
classBeming
} from "react-classnaming"
// Default export is the most simple function
import classNaming from "react-classnaming"
import type {
// Type to declare component's self CSS classes
ClassNamesProperty,
// Type to gather required CSS classes of sub-components
ClassNames,
// = string | undefined – type to declare CSS class, global or local= {className: string}
ClassHash,
// – useful shortcut`
ClassNamed
} from "react-classnaming"
Basic usage
Example of simple CSS classes conditioning – ./\__tests__/readme.spec.tsx:9
`tsx
import classNaming from "react-classnaming"
type Props = {
isValid: boolean
readOnly: boolean
}
// isValid = false, readOnly = false
function FormButtons({isValid, readOnly}: Props) {
const cssClasses = classNaming()
const buttonClass = cssClasses({"button": true}) // "button"
return <>
...buttonClass // className="button"
}>Close
...buttonClass({"button--disabled": readOnly}) // className="button"
}>Reset
{ / className="button_submit button button--disabled" / }
}
`
As shown, producing function classNaming returns a multipurpose object. It can be
- recalled to stack more CSS classes on conditions: anotherClass = someClass({...})({...})
- destructed in component's props as singleton:
- used as a string: `${someClass} ${anotherClass} Demos
You can find demonstration with all main points in folder ./\__examples__/, in addition .test. and .spec.. 
Getting more
$3
Conditions with falsy values may lead to hardly caught bugs due to not obvious behavior for humans. In addition, as a possible true shortcut, the value can be not empty string as class-hash from CSS-module, and undefined for global CSS-class or modules simulation. Thus, to not keep in mind that undefined appears to be a truthy condition, it is prohibited on TypeScript level to mix in value type boolean with ClassHash = string | undefined and not allowed to use any other types like 0, null. ./\__tests__/readme.spec.tsx:43
$3
There can be only ONE condition for each class in call pipe. Already conditioned classes are propagated to next call type notation so you can see currently stacked with according modality: true, false or boolean. ./\__tests__/readme.spec.tsx:55
$3
Only declared CSS classes will be allowed as keys with IDE hint on possibilities – ./\__tests__/readme.spec.tsx:71
``diff
+ import type { ClassHash, ClassNamesProperty } from "react-classnaming"
+ type MyClassNames = ClassNamesProperty<{
+ button: ClassHash
+ button_submit: ClassHash
+ "button--disabled": ClassHash
+ }>
- const cssClasses = classNaming()
+ const cssClasses = classNaming
`
$3
It is possible to use BEM as condition query. With explicitly declared CSS classes (i.e. via postcss-plugin-d-ts) TS and IDE will check and hint on available blocks, elements, modifiers and values. ./\__tests__/readme.spec.tsx:165
`diff
import {
- classNaming
+ classBeming
} from "react-classnaming"
- const cssClasses = classNaming
+ const bemClasses = classBeming
`
Reference
$3
Shortcut for {className: string}
. $3
For serving global and local CSS classes and not moduled CSS stylesheets. CSS-module will be imported as {[cssClasses: string]: string}, while for ordinary CSS import require returns just empty object {}. Their common notation is {[cssClasses: string]: string | undefined} , thus type ClassHash = string | undefined$3
Sets context for further type checks in supplying and toggling.
typescript
classNaming()
classNaming()
classNaming()
classNaming({classnames: require("./some.css")})
classNaming({classnames: module_css, className})
classNaming(this.props)
`
Returns pipe-able (recallable) callback, that also can be destructed as or stringifyed`tsx
const cssClasses = classNaming(...)
const btnClass = cssClasses({ button })return
${btnClass}} />
}/>
`On TS-level checks that Component's propagated
and certain CSS-class are conditioned once`typescript
const conditionForClass1: boolean = false
const containerClass = classes(true, {class1: conditionForClass1})const withClass1Twice = containerClass({
class2: true,
//@ts-expect-error – TS tracks that in chain there's only 1 place for class to be conditionally included
class1: otherCondiition
})
const withClassNameTwice = containerClass(
//@ts-expect-error - Same for
className - it is already added
true
)
`On
hovering will be tooltip with already conditioned classes under this chain$3
Sets context to returned function for using BEM conditioned CSS classes queries. General argument's shape is
`typescript
// .src/bem.types.ts#L84-L90
type BemInGeneral = {
[base: string]: undefined | boolean | string
| (false|string)[]
| {
[mod: string]: undefined | boolean | string
}
}
`Output logic: ./src/bem.core.test.ts:13
Featured example: \./\__tests__/readme.spec.tsx:191
---
$3
Default options BEM naming:
- Modifier's and value's separator is a double hyphen
- Element's separator is a double underscore It is required to change this options twice, both on JS (
) and TS namespace ReactClassNaming { interface BemOptions {...} }) levels. See ./\__recipes__/$3
Function to map
classnames to string props of some (i.e. 3rd-party) component.`tsx
const { Root } = classnames
const mapping = classNamesMap(classnames)
Checked___true: classes({ "Item--active": true }),
Checked___false: {}
})} />
`For hint will be used such props of target component that can be assigned to
. After calling mapping function and setting other properties, usual TypeScript will check for presence of target's required properties and other ordinary for TS things.
$3
Declaration of self Component's
classnamestypescript
type MyClasses = ClassNamesProperty<{
class1: ClassHash
class2: ClassHash
}>
`
Can be restricted to use classes only from CSS module. Note Currently no IDE's tooltip for hintstypescript
type MyProps = ClassNamesProperty<
typeof some_module_css,
//@ts-expect-error
{class1: ClassHash, class2: ClassHash, unknownClass: ClassHash}
>
`$3
Collects/gathers required
from used sub-Components`typescript
type MyProps = ClassNames // === ClassNamed === {className: string}
type MyProps = ClassNames // {classnames: Props["classnames"]}
type MyProps = ClassNames
type MyProps = ClassNames
`tsx
type Props = ClassNames
function Component({className, classnames, "classnames": {Sub1Class}}: Props) {
const classes = classNaming({classnames, className})
return
classnames
}}/>
}
`$3
Obtain
-object from props of functional component, class component or props type`typescript
ClassNamesFrom;
ClassNamesFrom;
`$3
Identical function or returning constant
for keys check of not used classes in components tree `tsx
import css from "./page.scss"
import App from "./App.tsx"ReactDOM.render(
`
- Dummies shape
tsx
`
- Checks CSS with defined (not indexed) classes keys. To produce such declaration you can use package .
`tsx
import type { ClassNamesFrom } from "react-classnaming/types";
import css_module from "./some.css"; // With class .never-used {...}
//@ts-expect-error Property 'never-used' is missing
{} as ClassNamesFrom
)} />;
Misc
$3
#### Using CSS-modules or simulation
It is possible to use CSS modules or simulation without "context" by supplying class-hash value with variable ./\__tests__/readme.spec.tsx:114
diff
// CSS-module, assuming "button" will be replaced with "BTN"
+ import css_module from "./button.module.css"
+ const { button } = css_module
// Module simulation
+ type CssModuleSimulation = { button_submit: ClassHash }
+ const { button_submit } = {} as CssModuleSimulation
type MyClassNames = ClassNamesProperty<
+ typeof css_module &
+ CssModuleSimulation &
{
- button: ClassHash
- button_submit: ClassHash
"button--disabled": ClassHash
}
>- const buttonClass = cssClasses({ button: true })
+ const buttonClass = cssClasses({ button })
- "button_submit": true,
+ button_submit,
"button--disabled": readOnly || !isValid
})}>Submit
`$3
See src/versus-classnames.test.ts
//TODO Copy here the most significant TS errors
#### No css-modules, just simulation
tsx
import classnames from "classnames"
// VERSUS
import css from "./some.css"
import classNaming, {classNamesCheck} from "react-classnaming"
import type {ClassNames} from "react-classnaming"
const { class1,
//@ts-expect-error
whatever
} = classNamesCheck<...>(css)
const props: ClassNames<"class2"> = {"classnames": css}
const {class2} = props.classnames
${classNaming({class1, class2})}} />
`#### CSS module
tsx
import module_css from "./some.module.css" // {"class1": "hash1", "class2": "hash2"}import classnames_bind from "classnames/bind"
const cx = classnames_bind.bind(module_css)
// No error on redundant CSS-class
// VERSUS
import classNaming from "react-classnaming"
const clases = classNaming({classnames: module_css})
//@ts-expect-error Argument of type '"class3"' is not assignable to parameter
``