Depercolator

This tool is a swiss army knife for converting coffeescript files to javascript. It relies on several other tools to ease the conversion process and create idiomatic javascript and JSX.

• cjsx-transform for adding jsx support to decaffeinate
• decaffeinate converts coffeescript to idiomatic javascript
• react-codemod for converting React.createElement calls back to JSX
• prettier-eslint For final formatting and cleanup

Learn more from our blog on converting our React codebase from CoffeeScript to ES6.

Installation

npm i -g depercolator

or

yarn global add depercolator

Usage

depercolate <file> [options]

Options

• -o, --output [filepath]: Change path of resulting file (defaults to same path as original with a different extension)
• --skip-prettier: Do not reformat the file with prettier (default is false)

Decaffeinate options

Most options from decaffeinate can be passed through to the underlying command

• --modernize-js: Treat the input as JavaScript and only run the JavaScript-to-JavaScript transforms, modifying the file(s) in-place.
• --literate: Treat the input file as Literate CoffeeScript.
• --disable-suggestion-comment: Do not include a comment with followup suggestions at the top of the output file.
• --no-array-includes: Do not use Array.prototype.includes in generated code.
• --use-optional-chaining: Use the upcoming optional chaining syntax for operators like ?..
• --use-js-modules: Convert require and module.exports to import and export.
• --loose-js-modules: Allow named exports when converting to JS modules.
• --safe-import-function-identifiers: Comma-separated list of function names that may safely be in the import/require section of the file. All other function calls will disqualify later requires from being converted to imports.
• --prefer-let: Use let instead of const for most variables in output code.
• --loose: Enable all --loose... options.
• --loose-default-params: Convert CS default params to JS default params.
• --loose-for-expressions: Do not wrap expression loop targets in Array.from.
• --loose-for-of: Do not wrap JS for...of loop targets in Array.from.
• --loose-includes: Do not wrap in Array.from when converting in to includes.
• --loose-comparison-negation: Allow unsafe simplifications like !(a > b) to a <= b.
• --disable-babel-constructor-workaround: Never include the Babel/TypeScript workaround code to allow this before super in constructors.
• --disallow-invalid-constructors: Give an error when constructors use this before super or omit the super call in a subclass.

Prettier options

Most options from prettier can be passed through to the underlying command

• --no-bracket-spacing: Do not print spaces between brackets.
• --jsx-bracket-same-line: Put > on the last line instead of at a new line.
• --parser <flow|babylon|typescript|css|less|scss|json|graphql|markdown>: Which parser to use
• --print-width <int>: The line length where Prettier will try wrap.
• --no-prose-wrap: Do not wrap prose. (markdown)
• --no-semi: Do not print semicolons, except at the beginning of lines which may need them.
• --single-quote: Use single quotes instead of double quotes.
• --tab-width <int>: Number of spaces per indentation level.
• --trailing-comma <none|es5|all>: Print trailing commas wherever possible when multi-line.
• --use-tabs: Indent with tabs instead of spaces.