Target Resolution

/**
 * Resolves compilation targets from various input formats
 * @param inputTargets - Target configuration including browsers, esmodules, and individual targets
 * @param options - Additional options for target resolution
 * @returns Normalized targets object with version strings
 */
function getTargets(inputTargets?: InputTargets, options?: GetTargetsOption): Targets;

interface InputTargets extends Targets {
  /** Browserslist query string or array of queries */
  browsers?: string | ReadonlyArray<string>;
  /** ES modules support flag - true, false, or "intersect" */
  esmodules?: boolean | "intersect";
}

interface GetTargetsOption {
  /** Directory path to start searching for browserslist config (default: ".") */
  configPath?: string;
  /** Explicit path to browserslist config file */
  configFile?: string;
  /** Environment name for browserslist config */
  browserslistEnv?: string;
  /** Skip automatic browserslist config loading */
  ignoreBrowserslistConfig?: boolean;
  /** Callback when browserslist config is found */
  onBrowserslistConfigFound?: (configFile: string) => void;
}

interface Targets {
  [target in Target]?: string;
}

type Target = 
  | "node" | "deno" | "chrome" | "opera" | "edge" | "firefox" 
  | "safari" | "ie" | "ios" | "android" | "electron" | "samsung" | "rhino" | "opera_mobile";

import getTargets from "@babel/helper-compilation-targets";

// Basic target specification
const targets1 = getTargets({
  chrome: 60,
  firefox: "55.0",
  node: "14.15.0"
});
// Result: { chrome: "60.0.0", firefox: "55.0.0", node: "14.15.0" }

// Using browserslist queries
const targets2 = getTargets({
  browsers: ["last 2 versions", "> 1%"]
});

// ES modules support
const targets3 = getTargets({
  browsers: "defaults",
  esmodules: true
});

// With configuration options
const targets4 = getTargets({
  browsers: "defaults"
}, {
  configPath: "./my-app",
  browserslistEnv: "production",
  onBrowserslistConfigFound: (file) => console.log(`Using config: ${file}`)
});

/**
 * Validates that browsers input is a valid browserslist query
 * @param browsers - Potential browserslist query
 * @returns True if valid query format
 */
function isBrowsersQueryValid(browsers: unknown): boolean;

import { isBrowsersQueryValid } from "@babel/helper-compilation-targets";

console.log(isBrowsersQueryValid("last 2 versions")); // true
console.log(isBrowsersQueryValid(["chrome > 60", "firefox > 55"])); // true  
console.log(isBrowsersQueryValid(123)); // false
console.log(isBrowsersQueryValid({ chrome: 60 })); // false

const TargetNames: {
  readonly node: "node";
  readonly deno: "deno";
  readonly chrome: "chrome";
  readonly opera: "opera";
  readonly edge: "edge";
  readonly firefox: "firefox";
  readonly safari: "safari";
  readonly ie: "ie";
  readonly ios: "ios";
  readonly android: "android";
  readonly electron: "electron";
  readonly samsung: "samsung";
  readonly rhino: "rhino";
  readonly opera_mobile: "opera_mobile";
};

const unreleasedLabels: {
  readonly safari: "tp";
};

/**
 * Validates that browsers input is a valid browserslist query
 * @param browsers - Potential browserslist query
 * @returns True if valid query format
 */
function isBrowsersQueryValid(browsers: unknown): boolean;

import { TargetNames, unreleasedLabels, isBrowsersQueryValid } from "@babel/helper-compilation-targets";

// Check valid target names
console.log(TargetNames.chrome); // "chrome"
console.log(TargetNames.node); // "node"

// Check for unreleased labels
console.log(unreleasedLabels.safari); // "tp"

// Validate browser queries
console.log(isBrowsersQueryValid("last 2 versions")); // true
console.log(isBrowsersQueryValid(["chrome > 60", "firefox > 55"])); // true  
console.log(isBrowsersQueryValid(123)); // false