stylelint/lib/augmentConfig.js

A mighty, modern CSS linter.

/* @flow */
'use strict';

const _ = require('lodash');
const configurationError = require('./utils/configurationError');
const dynamicRequire = require('./dynamicRequire');
const getModulePath = require('./utils/getModulePath');
const globjoin = require('globjoin');
const normalizeRuleSettings = require('./normalizeRuleSettings');
const path = require('path');
const requireRule = require('./requireRule');

// - Merges config and configOverrides
// - Makes all paths absolute
// - Merges extends
function augmentConfigBasic(
	stylelint /*: stylelint$internalApi*/,
	config /*: stylelint$config*/,
	configDir /*: string*/,
	allowOverrides /*:: ?: boolean*/,
) /*: Promise<stylelint$config>*/ {
	return Promise.resolve()
		.then(() => {
			if (!allowOverrides) return config;

			return _.merge(config, stylelint._options.configOverrides);
		})
		.then((augmentedConfig) => {
			return extendConfig(stylelint, augmentedConfig, configDir);
		})
		.then((augmentedConfig) => {
			return absolutizePaths(augmentedConfig, configDir);
		});
}

// Extended configs need to be run through augmentConfigBasic
// but do not need the full treatment. Things like pluginFunctions
// will be resolved and added by the parent config.
function augmentConfigExtended(
	stylelint /*: stylelint$internalApi*/,
	cosmiconfigResultArg /*: ?{
     config: stylelint$config,
     filepath: string,
   }*/,
) /*: Promise<?{ config: stylelint$config, filepath: string }>*/ {
	const cosmiconfigResult = cosmiconfigResultArg; // Lock in for Flow

	if (!cosmiconfigResult) return Promise.resolve(null);

	const configDir = path.dirname(cosmiconfigResult.filepath || '');
	const cleanedConfig = _.omit(cosmiconfigResult.config, 'ignoreFiles');

	return augmentConfigBasic(stylelint, cleanedConfig, configDir).then((augmentedConfig) => {
		return {
			config: augmentedConfig,
			filepath: cosmiconfigResult.filepath,
		};
	});
}

function augmentConfigFull(
	stylelint /*: stylelint$internalApi*/,
	cosmiconfigResultArg /*: ?{
   config: stylelint$config,
   filepath: string,
  }*/,
) /*: Promise<?{ config: stylelint$config, filepath: string }>*/ {
	const cosmiconfigResult = cosmiconfigResultArg; // Lock in for Flow

	if (!cosmiconfigResult) return Promise.resolve(null);

	const config = cosmiconfigResult.config;
	const filepath = cosmiconfigResult.filepath;

	const configDir = stylelint._options.configBasedir || path.dirname(filepath || '');

	return augmentConfigBasic(stylelint, config, configDir, true)
		.then((augmentedConfig) => {
			return addPluginFunctions(augmentedConfig);
		})
		.then((augmentedConfig) => {
			return addProcessorFunctions(augmentedConfig);
		})
		.then((augmentedConfig) => {
			if (!augmentedConfig.rules) {
				throw configurationError(
					'No rules found within configuration. Have you provided a "rules" property?',
				);
			}

			return normalizeAllRuleSettings(augmentedConfig);
		})
		.then((augmentedConfig) => {
			return {
				config: augmentedConfig,
				filepath: cosmiconfigResult.filepath,
			};
		});
}

// Make all paths in the config absolute:
// - ignoreFiles
// - plugins
// - processors
// (extends handled elsewhere)
function absolutizePaths(
	config /*: stylelint$config*/,
	configDir /*: string*/,
) /*: stylelint$config*/ {
	if (config.ignoreFiles) {
		config.ignoreFiles = [].concat(config.ignoreFiles).map((glob) => {
			if (path.isAbsolute(glob.replace(/^!/, ''))) return glob;

			return globjoin(configDir, glob);
		});
	}

	if (config.plugins) {
		config.plugins = [].concat(config.plugins).map((lookup) => {
			return getModulePath(configDir, lookup);
		});
	}

	if (config.processors) {
		config.processors = absolutizeProcessors(config.processors, configDir);
	}

	return config;
}

// Processors are absolutized in their own way because
// they can be and return a string or an array
function absolutizeProcessors(
	processors /*: stylelint$configProcessors*/,
	configDir /*: string*/,
) /*: stylelint$configProcessors*/ {
	const normalizedProcessors = Array.isArray(processors) ? processors : [processors];

	return normalizedProcessors.map((item) => {
		if (typeof item === 'string') {
			return getModulePath(configDir, item);
		}

		return [getModulePath(configDir, item[0]), item[1]];
	});
}

function extendConfig(
	stylelint /*: stylelint$internalApi*/,
	config /*: stylelint$config*/,
	configDir /*: string*/,
) /*: Promise<stylelint$config>*/ {
	if (config.extends === undefined) return Promise.resolve(config);

	const normalizedExtends = Array.isArray(config.extends) ? config.extends : [config.extends];

	const originalWithoutExtends = _.omit(config, 'extends');
	const loadExtends = normalizedExtends.reduce((resultPromise, extendLookup) => {
		return resultPromise.then((resultConfig) => {
			return loadExtendedConfig(stylelint, resultConfig, configDir, extendLookup).then(
				(extendResult) => {
					if (!extendResult) return resultConfig;

					return mergeConfigs(resultConfig, extendResult.config);
				},
			);
		});
	}, Promise.resolve(originalWithoutExtends));

	return loadExtends.then((resultConfig) => {
		return mergeConfigs(resultConfig, originalWithoutExtends);
	});
}

function loadExtendedConfig(
	stylelint /*: stylelint$internalApi*/,
	config /*: stylelint$config*/,
	configDir /*: string*/,
	extendLookup /*: string*/,
) /*: Promise<?{ config: stylelint$config, filepath: string }>*/ {
	const extendPath = getModulePath(configDir, extendLookup);

	return stylelint._extendExplorer.load(extendPath);
}

// When merging configs (via extends)
// - plugin and processor arrays are joined
// - rules are merged via Object.assign, so there is no attempt made to
//   merge any given rule's settings. If b contains the same rule as a,
//   b's rule settings will override a's rule settings entirely.
// - Everything else is merged via Object.assign
function mergeConfigs(a /*: stylelint$config*/, b /*: stylelint$config*/) /*: stylelint$config*/ {
	const pluginMerger = {};

	if (a.plugins || b.plugins) {
		pluginMerger.plugins = [];

		if (a.plugins) {
			pluginMerger.plugins = pluginMerger.plugins.concat(a.plugins);
		}

		if (b.plugins) {
			pluginMerger.plugins = _.uniq(pluginMerger.plugins.concat(b.plugins));
		}
	}

	const processorMerger = {};

	if (a.processors || b.processors) {
		processorMerger.processors = [];

		if (a.processors) {
			processorMerger.processors = processorMerger.processors.concat(a.processors);
		}

		if (b.processors) {
			processorMerger.processors = _.uniq(processorMerger.processors.concat(b.processors));
		}
	}

	const rulesMerger = {};

	if (a.rules || b.rules) {
		rulesMerger.rules = Object.assign({}, a.rules, b.rules);
	}

	const result = Object.assign({}, a, b, processorMerger, pluginMerger, rulesMerger);

	return result;
}

function addPluginFunctions(config /*: stylelint$config*/) /*: stylelint$config*/ {
	if (!config.plugins) return config;

	const normalizedPlugins = Array.isArray(config.plugins) ? config.plugins : [config.plugins];

	const pluginFunctions = normalizedPlugins.reduce((result, pluginLookup) => {
		let pluginImport = dynamicRequire(pluginLookup);

		// Handle either ES6 or CommonJS modules
		pluginImport = pluginImport.default || pluginImport;

		// A plugin can export either a single rule definition
		// or an array of them
		const normalizedPluginImport = Array.isArray(pluginImport) ? pluginImport : [pluginImport];

		normalizedPluginImport.forEach((pluginRuleDefinition) => {
			if (!pluginRuleDefinition.ruleName) {
				throw configurationError(
					'stylelint v3+ requires plugins to expose a ruleName. ' +
						`The plugin "${pluginLookup}" is not doing this, so will not work ` +
						'with stylelint v3+. Please file an issue with the plugin.',
				);
			}

			if (!_.includes(pluginRuleDefinition.ruleName, '/')) {
				throw configurationError(
					'stylelint v7+ requires plugin rules to be namspaced, ' +
						'i.e. only `plugin-namespace/plugin-rule-name` plugin rule names are supported. ' +
						`The plugin rule "${pluginRuleDefinition.ruleName}" does not do this, so will not work. ` +
						'Please file an issue with the plugin.',
				);
			}

			result[pluginRuleDefinition.ruleName] = pluginRuleDefinition.rule;
		});

		return result;
	}, {});

	config.pluginFunctions = pluginFunctions;

	return config;
}

function normalizeAllRuleSettings(config /*: stylelint$config*/) /*: stylelint$config*/ {
	const normalizedRules = {};

	if (!config.rules) return config;

	Object.keys(config.rules).forEach((ruleName) => {
		const rawRuleSettings = _.get(config, ['rules', ruleName]);

		const rule = requireRule(ruleName) || _.get(config, ['pluginFunctions', ruleName]);

		if (!rule) {
			normalizedRules[ruleName] = [];
		} else {
			normalizedRules[ruleName] = normalizeRuleSettings(
				rawRuleSettings,
				ruleName,
				_.get(rule, 'primaryOptionArray'),
			);
		}
	});

	config.rules = normalizedRules;

	return config;
}

// Given an array of processors strings, we want to add two
// properties to the augmented config:
// - codeProcessors: functions that will run on code as it comes in
// - resultProcessors: functions that will run on results as they go out
//
// To create these properties, we need to:
// - Find the processor module
// - Intialize the processor module by calling its functions with any
//   provided options
// - Push the processor's code and result processors to their respective arrays
const processorCache = new Map();

function addProcessorFunctions(config /*: stylelint$config*/) /*: stylelint$config*/ {
	if (!config.processors) return config;

	const codeProcessors = [];
	const resultProcessors = [];

	[].concat(config.processors).forEach((processorConfig) => {
		const processorKey = JSON.stringify(processorConfig);

		let initializedProcessor;

		if (processorCache.has(processorKey)) {
			initializedProcessor = processorCache.get(processorKey);
		} else {
			processorConfig = [].concat(processorConfig);
			const processorLookup = processorConfig[0];
			const processorOptions = processorConfig[1];
			let processor = dynamicRequire(processorLookup);

			processor = processor.default || processor;
			initializedProcessor = processor(processorOptions);
			processorCache.set(processorKey, initializedProcessor);
		}

		if (initializedProcessor && initializedProcessor.code) {
			codeProcessors.push(initializedProcessor.code);
		}

		if (initializedProcessor && initializedProcessor.result) {
			resultProcessors.push(initializedProcessor.result);
		}
	});

	config.codeProcessors = codeProcessors;
	config.resultProcessors = resultProcessors;

	return config;
}

module.exports = { augmentConfigExtended, augmentConfigFull };