hexo_postname

new_post_path.js

hexo的文章生成名称经过newPostFilter这个过滤器来生成的：

ctx.execFilter('new_post_path', data, {
     args: [replace],
     context: ctx
   })

function newPostPathFilter(data, replace){
  /* jshint validthis: true */
  data = data || {};//data里带有文章标题

  var sourceDir = this.source_dir;//this指向hexo实例
  //this.source_dir = pathFn.join(base, 'source') + sep; hexo/index.js
  var draftDir = pathFn.join(sourceDir, '_drafts');
  var postDir = pathFn.join(sourceDir, '_posts');
  var config = this.config;
  var newPostName = config.new_post_name;//默认为:title.md
  var permalinkDefaults = config.permalink_defaults;
  var path = data.path;//默认为空
  var layout = data.layout;//默认为空
  var slug = data.slug;//文章标题
  var target = '';

  if (!permalink || permalink.rule !== newPostName){
    permalink = new Permalink(newPostName); //固定链接 :title.md
  }

  if (path){
    switch (layout){
      case 'page':
        target = pathFn.join(sourceDir, path);
        break;

      case 'draft':
        target = pathFn.join(draftDir, path);
        break;

      default:
        target = pathFn.join(postDir, path);
    }
  } else if (slug){
    switch (layout){
      case 'page':
        target = pathFn.join(sourceDir, slug, 'index');
        break;

      case 'draft':
        target = pathFn.join(draftDir, slug);
        break;

      default:
        var date = moment(data.date || Date.now());//moment库
        var keys = Object.keys(data);
        var key = '';

        var filenameData = {
          year: date.format('YYYY'),
          month: date.format('MM'),
          i_month: date.format('M'),
          day: date.format('DD'),
          i_day: date.format('D'),
          title: slug
        };

        for (var i = 0, len = keys.length; i < len; i++){
          key = keys[i];
          if (!reservedKeys[key]) filenameData[key] = data[key];
        }
        //console.log('defaults:'+ _.defaults(filenameData, permalinkDefaults).title);
        //console.log('postDir:'+postDir);

        //permalink.stringify 正则替换把permalink中的title替换为filenamedata中的titile，就是文章标题
        //_.defaults lodash库
        //Assigns own enumerable properties of source object(s) to the destination object for all destination properties that resolve to undefined. Once a property is set, additional values of the same property are ignored.

        target = pathFn.join(postDir, permalink.stringify(
          _.defaults(filenameData, permalinkDefaults)));
    }
  } else {
    return Promise.reject(new TypeError('Either data.path or data.slug is required!'));
  }

  if (!pathFn.extname(target)){
    target += pathFn.extname(newPostName) || '.md';
  }

  if (replace){
    return Promise.resolve(target);
  } else {
    return fs.ensurePath(target);
  }
}

hexo-fs/lib/fs.js

function ensurePath(path, callback){
  if (!path) throw new TypeError('path is required!');

  return exists(path).then(function(exist){
    if (!exist) return path;

    return readdirAsync(dirname(path)).then(function(files){
      return _findUnusedPath(path, files);
    });
  }).nodeify(callback);
}

function exists(path, callback){
  if (!path) throw new TypeError('path is required!');

  return new Promise(function(resolve, reject){
    fs.exists(path, function(exist){
      resolve(exist);
      if (typeof callback === 'function') callback(exist);
    });
  });
}

最终文件名的秘密就在这里,相同的文件名就自动加上数字

_findUnusedPath

function _findUnusedPath(path, files){
  var extname = pathFn.extname(path);
  var basename = pathFn.basename(path, extname);
  var regex = new RegExp('^' + escapeRegExp(basename) + '(?:-(\\d+))?' + escapeRegExp(extname) + '$');
  var item = '';
  var num = -1;
  var match, matchNum;

  for (var i = 0, len = files.length; i < len; i++){
    item = files[i];
    if (!regex.test(item)) continue;

    match = item.match(regex);
    matchNum = match[1] ? parseInt(match[1], 10) : 0;

    if (matchNum > num){
      num = matchNum;
    }
  }

  return join(dirname(path), basename + '-' + (num + 1) + extname);
}