baseline-detector

Detects the Baseline target of a project based on its source code.

baseline-detector statically analyses the JavaScript/TypeScript sources in a project, maps the web platform features it uses to their web-features Baseline status, and reports the overall Baseline target the project requires.

Install

npm install baseline-detector

TypeScript is an optional peer dependency. When it is available, type information is used to improve detection accuracy.

Usage

import {
  detectFeatures,
  detectBaselineTarget,
  detectBaselineYear,
} from 'baseline-detector';

const target = await detectBaselineTarget();
console.log(target); // e.g. { status: 'low', reason: 'array-flat' }

// The Baseline year the project targets (newest feature it relies on),
// or null if any feature is not yet Baseline.
const year = await detectBaselineYear();
console.log(year); // e.g. 2023

// The raw features detected, grouped by file.
const features = await detectFeatures();
for (const [file, ids] of features) {
  console.log(file, [...ids]);
}

By default the project in the current working directory is analysed. Pass a cwd to point elsewhere:

await detectBaselineTarget({ cwd: '/path/to/project' });

Source files are discovered from the directory's tsconfig.json rootDir (falling back to the cwd), respecting .gitignore.

API

| Export | Description | | --- | --- | | detectFeatures(options?) | Resolves to a Map<string, Set<string>> of feature IDs detected per file. | | detectBaselineTarget(options?) | Resolves to a BaselineTarget, { status, reason }, where status is the project's overall BaselineStatus ('high', 'low', or false) and reason is the feature ID that determined it (null when status is 'high'). | | detectBaselineYear(options?) | Resolves to the newest Baseline year the project targets, or null. |

License

MIT