-ke-bab-> 🍢

A library to convert text between different cases and formats.

import Kebab

let con = CaseConverter()
con.convert(text: "CaseConverter", from: .PascalCase, to: .snake_case) // case_converter
con.convert(text: "case_converter", from: .snake_case, to: .screamingKebabCase) // CASE-CONVERTER

Supported multiple-word identifier formats

The following formats from Wikipedia examples of multi-word identifier formats are supported by Kebab:

Formatting	Name(s)
twowords	flat case
TWOWORDS	upper flat case
twoWords	(lower) camelCase, dromedaryCase
TwoWords	PascalCase, Upper Camel Case, StudlyCase
two_words	snake_case, pothole_case
TWO_WORDS	SCREAMING_SNAKE_CASE, MACRO_CASE, CONSTANT_CASE
two_Words	camel_Snake_Case
Two_Words	Pascal_Snake_Case
two-words	kebab-case, dash-case, lisp-case
two|words	doner|case
TWO-WORDS	TRAIN-CASE, COBOL-CASE, SCREAMING-KEBAB-CASE
Two-Words	Train-Case, HTTP-Header-Case

Multi-word Identifier

MultiwordIdentifier defines input and output conversion formats. Enum cases are defined mathing their case format where possible:

public enum MultiWordIdentifier {
    case flatcase              // flatcase
    case UPPERFLATCASE         // UPPERFLATCASE
    case camelCase             // camelCase
    case PascalCase            // PascalCase
    case snake_case            // snake_case
    case MACRO_CASE            // MACRO_CASE
    case camel_Snake_Case      // camel_Snake_Case
    case Pascal_Snake_Case     // Pascal_Snake_Case
    case kebabCase             // kebak-case
    case trainCase             // Train-Case
    case cobolCase             // COBOL-CASE
    case donerCase             // doner|case
}

Synonyms / Aliases

The following aliases are also defined for convenience:

extension MultiWordIdentifier {
    public static let lowerCamelCase = Self.camelCase        // lowerCamelCase
    public static let dromedaryCase = Self.camelCase         // dromedaryCase
    public static let UpperCamelCase = Self.PascalCase       // UpperCamelCase
    public static let StudlyCase = Self.PascalCase           // StudlyCase
    public static let pothole_case = Self.snake_case         // pothole_case
    public static let SCREAMING_SNAKE_CASE = Self.MACRO_CASE // SCREAMING_SNAKE_CASE
    public static let CONSTANT_CASE = Self.MACRO_CASE        // CONSTANT_CASE
    public static let spineCase = Self.kebabCase             // spine-case
    public static let dashCase = Self.kebabCase              // dash-case
    public static let lispCase = Self.kebabCase              // lisp-case
    public static let httpHeaderCase = Self.trainCase        // Http-Header-Case
    public static let screamingKebabCase = Self.cobolCase    // SCREAMING-KEBAB-CASE
    public static let screamingTrainCase = Self.cobolCase    // SCREAMING-TRAIN-CASE
}

Usage

Case Converter

CaseConverter is the core of this library, and allows converting between all the formats listed above. Note that converting to flatcase or UPPERFLATCASE formats is non-reversible.

import Kebab

let con = CaseConverter()
con.convert(text: "CaseConverter", from: .PascalCase, to: .flatcase) // caseconverter
con.convert(text: "caseconverter", from: .flatcase, to: .PascalCase) // Caseconverter ⚠️

CaseConverter can also take plain text as input. This process will replace any non-alpanumeric characters with the proper separator (or no separator) depending on the format.

import Kebab

let con = CaseConverter()
con.convert(text: "A Title for a 100 Blog Post!", from: .plainText, to: .kebabCase)
// a-title-for-a-100-blog-post

Consecutive separators are removed.

import Kebab

let con = CaseConverter()
con.convert(text: "Too much $$ I would say!!", from: .plainText, to: .snake_case)
// too_much_i_would_say

Case Detector

While indicating the input format is preferrable (more performant), Kebab provides a case detector.

import Kebab

let detector = CaseDetector()
detector.detectCase(in: "this-is-kebab-case") // .kebabCase
detector.detectCase(in: "SOME_CONSTANT") // .MACRO_CASE

This allows to use CaseConverter without having to provide the input format (adding a performance penalty).

import Kebab

let con = CaseConverter()
con.convert(text: "this-is-kebab-case", to: .camelCase) // thisIsKebabCase

String Extensions

For convenience, a separate module KebabExtensions provides extensions for String, both for conversion and case detection.

import KebabExtensions

"Some-Http-Header".converted(to: .donerCase) // some|http|header
"GoodOldPascalCase".converted(to: .SCREAMING_SNAKE_CASE) // GOOD_OLD_PASCAL_CASE

"This_Is_Pascal_Snake_Case".detectCase() // .Pascal_Snake_Case

JSON Encoding/Decoding Strategies

camelCase (default) and snake_case key encoding/decoding strategies are both included in Foundation, so this library does not provide them.

This library however provides key encoding/decoding strategies for handling JSON payloads with keys encoded in either PascalCase or kebab-case. These are included in the module KebabJSON.

import KebabJSON

struct Dto: Codable {
    let propertyName: String
    let anotherProperty: Int
    // Note the lack of custom coding keys
}

let json = """
{
    "property-name": "Property Value",
    "another-property": 42
}
"""

let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromKebabCase  // decode `kebab-case` keys
let dto = try decoder.decode(Dto.self, from: Data(json.utf8))

let encoder = JSONEncoder()
encoder.keyEncodingStrategy = .convertToPascalCase  // encode `PascalCase` keys
let data = try encoder.encode(dto)
// { "PropertyName": "Property Value", "AnotherProperty": 42 }

Installation

Add Kebab to your Swift package:

// swift-tools-version:5.0
import PackageDescription

let package = Package(
  name: "YourProject",
  dependencies: [
    .package(url: "https://github.com/eneko/Kebab", from: "1.0.0"),
  ]
)

Requirements

Swift 5.0+

License

MIT

Contact

Twitter: @eneko