vc2c

The vc2c project can convert vue class APIs to vue composition APIs in Vue.js components written in Typescript.

Demo

Introduction

ASTConvertPlugins is the most important part of this project, it can convert AST to composition APIs.
Custom decorator in ASTConvertPlugins are supported, such as @Subscription.
See Writing a custom ASTConvert for more details.

Supports

The files to be converted must meet the criterias below:

• Scripts must be written in Typescript. (JavaScript may be supported in the future.)
• All syntax must be valid.
• Node.js >= 8.16

supported feature

• vue-class-component
  • Object
    • name
    • props
    • data
    • computed
    • methods
    • watch
    • intervalHook (ex: mounted)
    • provide / inject
    • mixins
    • extends
    • render
  • Class
    • className
    • computed
    • data
    • intervalHook (ex: mounted)
    • render
    • methods
    • Mixins
• vue-property-decorator
  • @Prop
  • @PropSync
  • @Model
  • @Watch
  • @Provide / @Inject
  • @ProvideReactive / @InjectReactive
  • @Emit
  • @Ref
• replace this to props, variable, or context.
• sort by dependency.

Usage

The vc2c project has both CLI and API interface.

CLI

# npm
npx vc2c single [cliOptions] <VueOrTSfilePath>

# yarn
yarn add vc2c
yarn vc2c single [cliOptions] <VueOrTSfilePath>

# volta
sudo volta install vc2c
vc2c single [cliOptions] <VueOrTSfilePath>

Options

-v, --view             Output file content on stdout, and no write file.
-o, --output           Output result file path.
-r, --root <root>      Set root path for calc file absolute path. Default:`process.cwd()`.
-c, --config <config>  Set vc2c config file path. Default: `'.vc2c.js'`.
-h, --help             Output usage information.

API

const { convert, convertFile } = require('vc2c')

// Get convert result script
const resultScript = convert(
  /* scriptContent */ fileContent, // cann't include vue file content, if vue file, only input script element content
  /* {Vc2cConfig} */ options
)

// Get FileInfo and scriptResult
const { file, result } = convertFile(
  /* VueOrTSfilePath */ filePath,
  /* rootPath */ cmdOptions.root,
  /* Vc2cConfigFilePath */ cmdOptions.config
)

Vc2c Config

{
  // root path for calc file absolute path, if in CLI, --root value will replace. default:`process.cwd()`
  root?: string
  // show debug message. default: `false`
  debug?: boolean,
  // if true, use @vue/composition-api. default: `false`
  compatible?: boolean
  // first setup function parameter name. default: `props`
  setupPropsKey?: string
  // second setup function parameter name. default: `context`
  setupContextKey?: string
  // Use custom version typescript. default: Typescript 3.7.3
  typesciprt?: typeof ts
  // Use custom version vue-template-compiler, please match your project vue versions. default: vue-template-compiler 2.6.11
  vueTemplateCompiler?: typeof vueTemplateCompiler
  // Use custom eslint file path. if file not exists, use default vc2c eslint config.  default: `.eslintrc.js`
  eslintConfigFile?: string
  // Use custom ASTConvertPlugins for ASTConvert and ASTTransform
  plugins?: ASTConvertPlugins
}

Plugins

ASTConvertPlugins

import * as ts from 'typescript'
// import { ASTConvertPlugins, ASTConverter, ASTTransform } from 'vc2c'
export interface ASTConvertPlugins {
  [ts.SyntaxKind.Decorator]: {
    // @Component decorator argument ASTConvert
    [ts.SyntaxKind.PropertyAssignment]: Array<ASTConverter<ts.PropertyAssignment>>
    [ts.SyntaxKind.MethodDeclaration]: Array<ASTConverter<ts.MethodDeclaration>>
  };
  // Class child AST will forEach ASTConverter until return ASTResult by AST SyntaxKind
  [ts.SyntaxKind.Identifier]: Array<ASTConverter<ts.Identifier>>
  [ts.SyntaxKind.HeritageClause]: Array<ASTConverter<ts.HeritageClause>>
  [ts.SyntaxKind.PropertyDeclaration]: Array<ASTConverter<ts.PropertyDeclaration>>
  [ts.SyntaxKind.GetAccessor]: Array<ASTConverter<ts.GetAccessorDeclaration>>
  [ts.SyntaxKind.SetAccessor]: Array<ASTConverter<ts.SetAccessorDeclaration>>
  [ts.SyntaxKind.MethodDeclaration]: Array<ASTConverter<ts.MethodDeclaration>>
  // When all ASTConvert finished, run ASTTransform.
  after: Array<ASTTransform>
}

ASTConvertPlugins process

• Vue Class @Component decorator Object:

  • Vc2c will parse object properties of @Component argument by running ASTConvert functions in plugins[ts.SyntaxKind.Decorator][property.kind as ts.SyntaxKind] array.
  • When ASTConvert returns a ASTResult, vc2c will record the ASTResult and proceed to the next object property.
  • If ASTConvert returns false, vc2c will run the next ASTConvert function in the array.

• Vue Class:

  • Vc2c will parse Class AST childs by running ASTConvert functions in plugins[AST.kind as ts.SyntaxKind] array.
  • When ASTConvert returns a ASTResult, vc2c will record the ASTResult and proceed to the next object property.
  • If ASTConvert returns false, vc2c will run the next ASTConvert function in the array.

• Transform:

  • Vc2c will run all ASTTransform functions in plugins.after array after finishing the two steps above.
  • You can use it to merge or sort AST. ex: computed, removeThis.

Tips

• You can use https://ts-ast-viewer.com/ to get Typescript ast.
• You can use built-in ASTConvert or ASTTransform in ASTConvertPlugins.

  import { BuiltInPlugins } from 'vc2c'
  const astConvert: ASTConvert = BuiltInPlugins.convertProp

• You cas use built-in typescript AST utils.

  import { getDecoratorNames, isInternalHook } from 'vc2c'

• ASTConvert functions must be placed in order by it's strictness in ASTConvertPlugins. Stricter function should be placed up front.
• If you want to use Vue any property, you can see link.

ASTConvert Example

• built-ins

Roadmap

• Add more TODO: comments on needed.
• Support more features.
• Convert project.