Analyses the languages of all files in a given folder or folders and collates the results.

Powered by github-linguist, although it doesn't need to be installed.

Node.js must be installed to be able to use LinguistJS.

LinguistJS is available on npm as linguist-js.

Install locally using npm install linguist-js and import it into your code like so:

const linguist = require('linguist-js');

Or install globally using npm install -g linguist-js and run using the CLI command linguist or linguist-js.

linguist --help
linguist-js --help

LinguistJS analyses a folder, or a dictionary of already-read file content, and determines what programming languages are used within.

As an example, take the following file structure:

/
| src
| | cli.js 1kB
| | index.ts 2kB
| readme.md 3kB
| no-lang 10B
| x.pluginspec 10B

(or, an object with keys "/src", "/src/cli.js", ... and preloaded file content)

Running LinguistJS on this will return the following JSON:

{
  "files": {
    "count": 5,
    "bytes": 6020,
    "lines": {
      "total": 100,
      "content": 90,
    },
    "results": {
      "/src/index.ts": "TypeScript",
      "/src/cli.js": "JavaScript",
      "/readme.md": "Markdown",
      "/no-lang": null,
      "/x.pluginspec": "Ruby",
    },
  },
  "languages": {
    "count": 3,
    "bytes": 6010,
    "lines": {
      "total": 90,
      "content": 80,
    },
    "results": {
      "JavaScript": { "bytes": 1000, "lines": { "total": 49, "content": 49 }, },
      "Markdown": { "bytes": 3000, "lines": { "total": 10, "content": 5 }, },
      "Ruby": { "bytes": 10, "lines": { "total": 1, "content": 1 }, },
      "TypeScript": { "bytes": 2000, "lines": { "total": 30, "content": 25 }, },
    },
  },
  "unknown": {
    "count": 1,
    "bytes": 10,
    "lines": {
      "total": 10,
      "content": 10,
    },
    "filenames": {
      "no-lang": 10,
    },
    "extensions": {},
  },
  "repository": {
    "JavaScript": { "type": "programming", "color": "#f1e05a" },
    "Markdown": { "type": "prose", "color": "#083fa1" },
    "Ruby": { "type": "programming", "color": "#701516" },
    "TypeScript": { "type": "programming", "color": "#2b7489" },
  }
}

• File paths in the output use only forward slashes as delimiters, even on Windows.
• Unless running in offline mode: do not rely on any language classification output from LinguistJS being unchanged between runs. Language data is fetched each run from the latest classifications of github-linguist. This data is subject to change at any time and may change the results of a run even when using the same version of Linguist.

import linguist from 'linguist-js';

// Analyse folder on disc
const folders = ['./src'];
const options = { keepVendored: false, quick: false };
const { files, languages, unknown, repository } = await linguist.analyseFolders(folder, options);

// Analyse file content from raw input
const fileContent = {
	['file1.ts']: '#!/usr/bin/env node',
	['file2.ts']: 'console.log("Example");',
	['ignoreme.js']: 'ignored!',
}
const options = { ignoredFiles: ['ignoreme.*'] };
const { files, languages, unknown, repository } = await linguist.analyseRawContent(fileContent, options);

Exports:

• analyseFolders(folders?, opts?): Analyse the language of all files found in a folder or folders.
  • folders (optional; string array): A list of folders to analyse (defaults to ['./']).
  • opts (optional; object): An object containing analyser options.
• analyseRawContent(folders?, opts?): Analyse the language of all files found in a folder or folders.
  • entry (optional; string or string array): A list of folders to analyse (defaults to ['./']).
  • opts (optional; object): An object containing analyser options.

Analyser options:

• ignoredFiles (string array): A list of file path globs to explicitly ignore.
• ignoredLanguages (string array): A list of languages to ignore.
• categories (string array): A list of programming language categories that should be included in the results. Defaults to ['data', 'markup', 'programming', 'prose'].
• childLanguages (boolean): Whether to display sub-languages instead of their parents when possible (defaults to false).
• quick (boolean): Whether to skip complex language analysis such as the checking of heuristics and gitattributes statements (defaults to false). Alias for checkAttributes:false, checkIgnored:false, checkDetected:false, checkHeuristics:false, checkShebang:false, checkModeline:false.
• offline (boolean): Whether to use pre-packaged metadata files instead of fetching them from GitHub at runtime (defaults to false).
• calculateLines (boolean): Whether to calculate line of code totals (defaults to true).
• keepVendored (boolean): Whether to keep vendored files (dependencies, etc) (defaults to false). Does nothing when fileContent is set.
• keepBinary (boolean): Whether binary files should be included in the output (defaults to false).
• relativePaths (boolean): Change the absolute file paths in the output to be relative to the current working directory (defaults to false).
• checkAttributes (boolean): Force the checking of .gitattributes files (defaults to true unless quick is set). Does nothing when fileContent is set.
• checkIgnored (boolean): Force the checking of .gitignore files (defaults to true unless quick is set). Does nothing when fileContent is set.
• checkDetected (boolean): Force files marked with linguist-detectable to show up in the output, even if the file is not part of the declared categories.
• checkHeuristics (boolean): Apply heuristics to ambiguous languages (defaults to true unless quick is set).
• checkShebang (boolean): Check shebang (#!) lines for explicit language classification (defaults to true unless quick is set).
• checkModeline (boolean): Check modelines for explicit language classification (defaults to true unless quick is set).

linguist --analyse [<folders...>] [<options...>]
linguist --help
linguist --version

• --analyse: Analyse the language of all files found in a folder or folders.
  • [<folders...>]: The folders to analyse (defaults to ./).
  • --ignoredFiles <globs...>: A list of file path globs to ignore.
  • --ignoredLanguages <languages...>: A list of languages to exclude from the output.
  • --categories <categories...>: A list of language categories that should be displayed in the output. Must be one or more of data, prose, programming, markup.
  • --childLanguages: Display sub-languages instead of their parents, when possible.
  • --json: Only affects the CLI output. Display the outputted language data as JSON.
  • --tree <traversal>: Only affects the CLI output. A dot-delimited traversal to the nested object that should be logged to the console instead of the entire output. Requires --json to be specified.
  • --listFiles: Only affects the visual CLI output. List each matching file and its size under each outputted language result. Does nothing if --json is specified.
  • --quick: Skip the checking of .gitattributes and .gitignore files for manual language classifications. Alias for --checkAttributes=false --checkIgnored=false --checkHeuristics=false --checkShebang=false --checkModeline=false.
  • --offline: Use pre-packaged metadata files instead of fetching them from GitHub at runtime.
  • --calculateLines: Calculate line of code totals from files.
  • --keepVendored: Include vendored files (auto-generated files, dependencies folder, etc) in the output.
  • --keepBinary: Include binary files in the output.
  • --relativePaths: Change the absolute file paths in the output to be relative to the current working directory.
  • --checkAttributes: Force the checking of .gitatributes files. Use alongside --quick to override it disabling this option.
  • --checkIgnored: Force the checking of .gitignore files. Use alongside --quick to override it disabling this option.
  • --checkDetected: Force files marked with linguist-detectable to show up in the output, even if the file is not part of the declared --categories. Use alongside --quick to override it disabling this option.
  • --checkHeuristics: Apply heuristics to ambiguous languages. Use alongside --quick to override it disabling this option.
  • --checkShebang: Check shebang (#!) lines for explicit classification. Use alongside --quick to override it disabling this option.
  • --checkModeline: Check modelines for explicit classification. Use alongside --quick to override it disabling this option.
• --help: Display the help message.
• --version: Display the current installed version of LinguistJS.