Update CLI internals

*   Refactor CLI to depend on unified-engine, which comes
    with lots of fixes and simplifications;
*   Add proper CLI tests.

.alexignore

@@ -1,6 +1,2 @@
-# Both `node_modules` and `bower_components` are
-# ignored by default:
-# node_modules/
-# bower_components/
-
+# `node_modules` is ignored by default.
 example.md

.gitignore

@@ -2,5 +2,6 @@
 *.log
 node_modules/
 .nyc_output/
+coverage/
 alex.js
 alex.min.js

cli.js

@@ -9,45 +9,19 @@
 
 'use strict';
 
-/* eslint-disable handle-callback-err */
-
 /* Dependencies. */
-var fs = require('fs');
-var bail = require('bail');
+var PassThrough = require('stream').PassThrough;
 var notifier = require('update-notifier');
 var meow = require('meow');
-var globby = require('globby');
-var hasMagic = require('glob').hasMagic;
-var minimatch = require('minimatch');
-var getStdin = require('get-stdin');
-var findDown = require('vfile-find-down');
-var findUp = require('vfile-find-up');
-var format = require('vfile-reporter');
-var toFile = require('to-vfile');
+var engine = require('unified-engine');
+var unified = require('unified');
+var markdown = require('remark-parse');
+var english = require('retext-english');
+var equality = require('retext-equality');
+var profanities = require('retext-profanities');
+var remark2retext = require('remark-retext');
+var report = require('vfile-reporter');
 var pack = require('./package');
-var alex = require('./');
-
-/* Methods. */
-var readFile = fs.readFileSync;
-var stat = fs.statSync;
-
-/* Constants. */
-var expextPipeIn = !process.stdin.isTTY;
-var IGNORE = '.alexignore';
-var RC = '.alexrc';
-var PACKAGE = 'package.json';
-var PACKAGE_FIELD = 'alex';
-var ENCODING = 'utf-8';
-var BACKSLASH = '\\';
-var SLASH = '/';
-var CD = './';
-var HASH = '#';
-var EMPTY = '';
-
-var defaultIgnore = [
-  'node_modules/',
-  'bower_components/'
-];
 
 var extensions = [
   'txt',
@@ -66,8 +40,7 @@ notifier({pkg: pack}).notify();
 /* Set-up meow. */
 var cli = meow({
   help: [
-    'Usage:  alex [<file> | <dir> ...] [-q, --quiet] [-w, --why] ' +
-        '[-t, --text]',
+    'Usage: alex [<glob> ...] [options ...]',
     '',
     'Options:',
     '',
@@ -83,238 +56,69 @@ var cli = meow({
     '  $ alex *.md !example.md',
     '  $ alex'
   ]
-});
-
-/* Set-up. */
-var exit = 0;
-var result = [];
-var why = Boolean(cli.flags.w || cli.flags.why);
-var quiet = Boolean(cli.flags.q || cli.flags.quiet);
-var fn = (cli.flags.t || cli.flags.text) ? 'text' : 'markdown';
-var globs = cli.input.length ? cli.input : [
-  '{docs/**/,doc/**/,}*.{' + extensions.join(',') + '}'
-];
-
-/* Exit. */
-process.on('exit', function () {
-  var report = format(result, {
-    verbose: why,
-    quiet: quiet
-  });
-
-  if (report) {
-    console.log(report);
+}, {
+  alias: {
+    v: 'version',
+    h: 'help',
+    t: 'text',
+    q: 'quiet',
+    w: 'why'
   }
-
-  process.exit(exit);
 });
 
-/**
- * Log a virtual file processed by alex.
- *
- * @param {VFile} file - Virtual file.
- */
-function log(file) {
-  result.push(file);
-
-  if (!exit && file.messages.length) {
-    exit = 1;
-  }
-}
+/* Set-up. */
+var globs = ['{docs/**/,doc/**/,}*.{' + extensions.join(',') + '}'];
 
-/**
- * Check if `file` matches `pattern`.
- *
- * @example
- *   match('baz.md', '*.md'); // true
- *
- * @param {string} filePath - File location.
- * @param {string} pattern - Glob pattern.
- * @return {boolean} - Whether `file` matches.
- */
-function match(filePath, pattern) {
-  return minimatch(filePath, pattern) || minimatch(filePath, pattern + '/**');
+/* istanbul ignore next - Bug in tests. Something hangs, at least. */
+if (cli.input.length) {
+  globs = cli.input;
 }
 
-/**
- * Check if `filePath` is matched included in `patterns`.
- *
- * @example
- *   shouldIgnore(['node_modules/'], 'node_modules/foo'); // true
- *
- * @param {Array.<string>} patterns - Glob patterns.
- * @param {string} filePath - File location.
- * @return {boolean} - Whether `filePath` should be ignored.
- */
-function shouldIgnore(patterns, filePath) {
-  var normalized = filePath.replace(BACKSLASH, SLASH).replace(CD, EMPTY);
-
-  return patterns.reduce(function (isIgnored, pattern) {
-    var isNegated = pattern.charAt(0) === '!';
-
-    if (isNegated) {
-      pattern = pattern.slice(1);
-    }
+var plain = unified().use(english).use(equality).use(profanities);
+var processor = plain;
 
-    if (pattern.indexOf(CD) === 0) {
-      pattern = pattern.slice(CD.length);
-    }
-
-    return match(normalized, pattern) ? !isNegated : isIgnored;
-  }, false);
+if (!cli.flags.text) {
+  processor = unified().use(markdown).use(remark2retext, plain);
 }
 
-/**
- * Load an ignore file.
- *
- * @param {string} ignore - File location.
- * @return {Array.<string>} - Patterns.
- */
-function loadIgnore(ignore) {
-  return readFile(ignore, ENCODING).split(/\r?\n/).filter(function (value) {
-    var line = value.trim();
-
-    return line.length && line.charAt(0) !== HASH;
+var filter = require.resolve('./filter.js');
+
+engine({
+  processor: processor,
+  globs: globs,
+  extensions: extensions,
+  configTransform: transform,
+  output: false,
+  out: false,
+  streamError: new PassThrough(),
+  rcName: '.alexrc',
+  packageField: 'alex',
+  ignoreName: '.alexignore',
+  plugins: [filter],
+  frail: true
+}, function (err, code, result) {
+  var out = report(err || result.files, {
+    verbose: cli.flags.why,
+    quiet: cli.flags.quiet
   });
-}
 
-/**
- * Factory to create a file filter based on bound ignore
- * patterns.
- *
- * @param {Array.<string>} ignore - Ignore patterns.
- * @param {Array.<string>} given - List of given file paths.
- * @return {Function} - Filter.
- */
-function filterFactory(ignore, given) {
-  /**
-   * Check whether a virtual file is applicable.
-   *
-   * @param {VFile} file - Virtual file.
-   */
-  return function (file) {
-    var filePath = file.filePath();
-    var extension = file.extension;
+  if (out) {
+    console.error(out);
+  }
 
-    if (given.indexOf(filePath) !== -1 || shouldIgnore(ignore, filePath)) {
-      return findDown.SKIP;
-    }
+  process.exit(code);
+});
 
-    return extension && extensions.indexOf(extension) !== -1;
-  };
-}
+function transform(raw) {
+  var allow = raw.allow || /* istanbul ignore next */ [];
 
-/**
- * Factory to create a file filter based on bound ignore
- * patterns.
- *
- * @param {Array.<VFile>} given - List of given files.
- * @param {Array.<string>} allow - List of allowed phrases.
- * @return {Function} - Process callback.
- */
-function processFactory(given, allow) {
-  /**
-   * Process all found files (and failed ones too).
-   *
-   * @param {Error} [err] - Finding error (not used by
-   *   vfile-find-down).
-   * @param {Array.<VFile>} [files] - Virtual files.
-   */
-  return function (err, files) {
-    given.concat(files || []).forEach(function (file) {
-      file.quiet = true;
+  return function (current) {
+    var plugins = {};
 
-      try {
-        file.contents = readFile(file.filePath(), ENCODING);
-      } catch (err) {
-        file.fail(err);
-      }
+    current = current.plugins && current.plugins[filter] && current.plugins[filter].allow;
 
-      alex[fn](file, allow);
+    plugins[filter] = {allow: [].concat(allow, current || [])};
 
-      log(file);
-    });
+    return {plugins: plugins};
   };
 }
-
-/* Either handle stdin(4) or patterns. */
-if (!cli.input.length && expextPipeIn) {
-  getStdin().then(function (value) {
-    var file = toFile('<stdin>');
-
-    file.contents = value;
-
-    alex(file);
-
-    log(file);
-  }, bail);
-} else {
-  globby(globs).then(function (filePaths) {
-    var files = [];
-    var given = [];
-
-    /* Check whether files are given directly that either
-     * do not exist or which might not match the default
-     * search patterns (based on extensions). */
-    globs.forEach(function (glob) {
-      if (hasMagic(glob)) {
-        return;
-      }
-
-      files.push(toFile(glob));
-      given.push(glob);
-
-      try {
-        if (!stat(glob).isFile()) {
-          files.pop();
-          given.pop();
-        }
-      } catch (err) { /* Empty. */ }
-    });
-
-    /* Search for an ignore file. */
-    findUp.one(IGNORE, function (err, file) {
-      var ignore = [];
-
-      try {
-        ignore = file && loadIgnore(file.filePath());
-      } catch (err) { /* Empty. */ }
-
-      ignore = defaultIgnore.concat(ignore || []);
-
-      /* Search for rc files. */
-      findUp.all([PACKAGE, RC], function (err, configs) {
-        var allow = [];
-        var length = configs && configs.length;
-        var index = -1;
-        var file;
-        var contents;
-
-        while (++index < length) {
-          file = configs[index];
-          file.contents = readFile(file.filePath(), ENCODING);
-          file.quiet = true;
-
-          try {
-            contents = JSON.parse(file.contents);
-
-            if (file.basename() === PACKAGE) {
-              contents = contents[PACKAGE_FIELD] || {};
-            }
-
-            allow = [].concat.apply(allow, contents.allow);
-          } catch (err) {
-            file.warn(err);
-            files.push(file);
-          }
-        }
-
-        findDown.all(
-          filterFactory(ignore, given),
-          filePaths,
-          processFactory(files, allow)
-        );
-      });
-    });
-  }, bail);
-}

filter.js

@@ -0,0 +1,14 @@
+'use strict';
+
+var control = require('remark-message-control');
+
+module.exports = filter;
+
+function filter(proc, options) {
+  var settings = options || /* istanbul ignore next */ {};
+  proc.use(control, {
+    name: 'alex',
+    disable: settings.allow,
+    source: ['retext-equality', 'retext-profanities']
+  });
+}