replace jest with ava

node_modules/ava/lib/load-config.js

@@ -0,0 +1,160 @@
+'use strict';
+const fs = require('fs');
+const path = require('path');
+const vm = require('vm');
+const isPlainObject = require('is-plain-object');
+const pkgConf = require('pkg-conf');
+
+const NO_SUCH_FILE = Symbol('no ava.config.js file');
+const MISSING_DEFAULT_EXPORT = Symbol('missing default export');
+const EXPERIMENTS = new Set();
+
+// *Very* rudimentary support for loading ava.config.js files containing an `export default` statement.
+const evaluateJsConfig = configFile => {
+	const contents = fs.readFileSync(configFile, 'utf8');
+	const script = new vm.Script(`'use strict';(()=>{let __export__;\n${contents.replace(/export default/g, '__export__ =')};return __export__;})()`, {
+		filename: configFile,
+		lineOffset: -1
+	});
+	return {
+		default: script.runInThisContext()
+	};
+};
+
+const loadJsConfig = ({projectDir, configFile = path.join(projectDir, 'ava.config.js')}) => {
+	if (!configFile.endsWith('.js')) {
+		return null;
+	}
+
+	const fileForErrorMessage = path.relative(projectDir, configFile);
+
+	let config;
+	try {
+		({default: config = MISSING_DEFAULT_EXPORT} = evaluateJsConfig(configFile));
+	} catch (error) {
+		if (error.code === 'ENOENT') {
+			return null;
+		}
+
+		throw Object.assign(new Error(`Error loading ${fileForErrorMessage}: ${error.message}`), {parent: error});
+	}
+
+	if (config === MISSING_DEFAULT_EXPORT) {
+		throw new Error(`${fileForErrorMessage} must have a default export, using ES module syntax`);
+	}
+
+	return {config, fileForErrorMessage};
+};
+
+const loadCjsConfig = ({projectDir, configFile = path.join(projectDir, 'ava.config.cjs')}) => {
+	if (!configFile.endsWith('.cjs')) {
+		return null;
+	}
+
+	const fileForErrorMessage = path.relative(projectDir, configFile);
+	try {
+		return {config: require(configFile), fileForErrorMessage};
+	} catch (error) {
+		if (error.code === 'MODULE_NOT_FOUND') {
+			return null;
+		}
+
+		throw Object.assign(new Error(`Error loading ${fileForErrorMessage}`), {parent: error});
+	}
+};
+
+const loadMjsConfig = ({projectDir, configFile = path.join(projectDir, 'ava.config.mjs')}) => {
+	if (!configFile.endsWith('.mjs')) {
+		return null;
+	}
+
+	const fileForErrorMessage = path.relative(projectDir, configFile);
+	try {
+		fs.readFileSync(configFile);
+	} catch (error) {
+		if (error.code === 'ENOENT') {
+			return null;
+		}
+
+		throw Object.assign(new Error(`Error loading ${fileForErrorMessage}`), {parent: error});
+	}
+
+	throw new Error(`AVA cannot yet load ${fileForErrorMessage} files`);
+};
+
+function loadConfig({configFile, resolveFrom = process.cwd(), defaults = {}} = {}) { // eslint-disable-line complexity
+	let packageConf = pkgConf.sync('ava', {cwd: resolveFrom});
+	const filepath = pkgConf.filepath(packageConf);
+	const projectDir = filepath === null ? resolveFrom : path.dirname(filepath);
+
+	if (configFile) {
+		configFile = path.resolve(configFile); // Relative to CWD
+		if (path.basename(configFile) !== path.relative(projectDir, configFile)) {
+			throw new Error('Config files must be located next to the package.json file');
+		}
+
+		if (!configFile.endsWith('.js') && !configFile.endsWith('.cjs') && !configFile.endsWith('.mjs')) {
+			throw new Error('Config files must have .js, .cjs or .mjs extensions');
+		}
+	}
+
+	const allowConflictWithPackageJson = Boolean(configFile);
+
+	let [{config: fileConf, fileForErrorMessage} = {config: NO_SUCH_FILE, fileForErrorMessage: undefined}, ...conflicting] = [
+		loadJsConfig({projectDir, configFile}),
+		loadCjsConfig({projectDir, configFile}),
+		loadMjsConfig({projectDir, configFile})
+	].filter(result => result !== null);
+
+	if (conflicting.length > 0) {
+		throw new Error(`Conflicting configuration in ${fileForErrorMessage} and ${conflicting.map(({fileForErrorMessage}) => fileForErrorMessage).join(' & ')}`);
+	}
+
+	if (fileConf !== NO_SUCH_FILE) {
+		if (allowConflictWithPackageJson) {
+			packageConf = {};
+		} else if (Object.keys(packageConf).length > 0) {
+			throw new Error(`Conflicting configuration in ${fileForErrorMessage} and package.json`);
+		}
+
+		if (fileConf && typeof fileConf.then === 'function') { // eslint-disable-line promise/prefer-await-to-then
+			throw new TypeError(`${fileForErrorMessage} must not export a promise`);
+		}
+
+		if (!isPlainObject(fileConf) && typeof fileConf !== 'function') {
+			throw new TypeError(`${fileForErrorMessage} must export a plain object or factory function`);
+		}
+
+		if (typeof fileConf === 'function') {
+			fileConf = fileConf({projectDir});
+			if (fileConf && typeof fileConf.then === 'function') { // eslint-disable-line promise/prefer-await-to-then
+				throw new TypeError(`Factory method exported by ${fileForErrorMessage} must not return a promise`);
+			}
+
+			if (!isPlainObject(fileConf)) {
+				throw new TypeError(`Factory method exported by ${fileForErrorMessage} must return a plain object`);
+			}
+		}
+
+		if ('ava' in fileConf) {
+			throw new Error(`Encountered ’ava’ property in ${fileForErrorMessage}; avoid wrapping the configuration`);
+		}
+	}
+
+	const config = {...defaults, nonSemVerExperiments: {}, ...fileConf, ...packageConf, projectDir};
+
+	const {nonSemVerExperiments: experiments} = config;
+	if (!isPlainObject(experiments)) {
+		throw new Error(`nonSemVerExperiments from ${fileForErrorMessage} must be an object`);
+	}
+
+	for (const key of Object.keys(experiments)) {
+		if (!EXPERIMENTS.has(key)) {
+			throw new Error(`nonSemVerExperiments.${key} from ${fileForErrorMessage} is not a supported experiment`);
+		}
+	}
+
+	return config;
+}
+
+module.exports = loadConfig;