summaryrefslogtreecommitdiff
path: root/node_modules/posthtml/lib/index.js
blob: 542c347bf1166e92a99870b61c8b7fd65b66b095 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
const pkg = require('../package.json')
const Api = require('./api.js')

let { parser } = require('posthtml-parser')
let { render } = require('posthtml-render')

/**
 * @author Ivan Voischev (@voischev),
 *         Ivan Demidov (@scrum)
 *
 * @requires api
 * @requires posthtml-parser
 * @requires posthtml-render
 *
 * @constructor PostHTML
 * @param {Array} plugins - An array of PostHTML plugins
 */
class PostHTML {
  constructor (plugins) {
  /**
   * PostHTML Instance
   *
   * @prop plugins
   * @prop options
   */
    this.version = pkg.version
    this.name = pkg.name
    this.plugins = typeof plugins === 'function' ? [plugins] : plugins || []
    this.source = ''

    /**
     * Tree messages to store and pass metadata between plugins
     *
     * @memberof tree
     * @type {Array} messages
     *
     * @example
     * ```js
     * export default function plugin (options = {}) {
     *   return function (tree) {
     *      tree.messages.push({
     *        type: 'dependency',
     *        file: 'path/to/dependency.html',
     *        from: tree.options.from
     *      })
     *
     *      return tree
     *   }
     * }
     * ```
     */
    this.messages = []

    /**
     * Tree method parsing string inside plugins.
     *
     * @memberof tree
     * @type {Function} parser
     *
     * @example
     * ```js
     * export default function plugin (options = {}) {
     *   return function (tree) {
     *      tree.match({ tag: 'include' }, function(node) {
     *          node.tag = false;
     *          node.content = tree.parser(fs.readFileSync(node.attr.src))
     *          return node
     *      })
     *
     *      return tree
     *   }
     * }
     * ```
     */
    this.parser = parser

    /**
     * Tree method rendering tree to string inside plugins.
     *
     * @memberof tree
     * @type {Function} render
     *
     * @example
     * ```js
     * export default function plugin (options = {}) {
     *    return function (tree) {
     *      var outherTree = ['\n', {tag: 'div', content: ['1']}, '\n\t', {tag: 'div', content: ['2']}, '\n'];
     *      var htmlWitchoutSpaceless = tree.render(outherTree).replace(/[\n|\t]/g, '');
     *      return tree.parser(htmlWitchoutSpaceless)
     *    }
     * }
     * ```
     */
    this.render = render

    // extend api methods
    Api.call(this)
  }

  /**
  * @this posthtml
  * @param   {Function} plugin - A PostHTML plugin
  * @returns {Constructor} - this(PostHTML)
  *
  * **Usage**
  * ```js
  * ph.use((tree) => { tag: 'div', content: tree })
  *   .process('<html>..</html>', {})
  *   .then((result) => result))
  * ```
  */
  use (...args) {
    this.plugins.push(...args)

    return this
  }

  /**
   * @param   {String} html - Input (HTML)
   * @param   {?Object} options - PostHTML Options
   * @returns {Object<{html: String, tree: PostHTMLTree}>} - Sync Mode
   * @returns {Promise<{html: String, tree: PostHTMLTree}>} - Async Mode (default)
   *
   * **Usage**
   *
   * **Sync**
   * ```js
   * ph.process('<html>..</html>', { sync: true }).html
   * ```
   *
   * **Async**
   * ```js
   * ph.process('<html>..</html>', {}).then((result) => result))
   * ```
   */
  process (tree, options = {}) {
    /**
     * ## PostHTML Options
     *
     * @type {Object}
     * @prop {?Boolean} options.sync - enables sync mode, plugins will run synchronously, throws an error when used with async plugins
     * @prop {?Function} options.parser - use custom parser, replaces default (posthtml-parser)
     * @prop {?Function} options.render - use custom render, replaces default (posthtml-render)
     * @prop {?Boolean} options.skipParse - disable parsing
     * @prop {?Array} options.directives - Adds processing of custom [directives](https://github.com/posthtml/posthtml-parser#directives).
     */
    this.options = options
    this.source = tree

    if (options.parser) parser = this.parser = options.parser
    if (options.render) render = this.render = options.render

    tree = options.skipParse
      ? tree || []
      : parser(tree, options)

    tree = [].concat(tree)

    // sync mode
    if (options.sync === true) {
      this.plugins.forEach((plugin, index) => {
        _treeExtendApi(tree, this)

        let result

        if (plugin.length === 2 || isPromise(result = plugin(tree))) {
          throw new Error(
            `Can’t process contents in sync mode because of async plugin: ${plugin.name}`
          )
        }

        // clearing the tree of options
        if (index !== this.plugins.length - 1 && !options.skipParse) {
          tree = [].concat(tree)
        }

        // return the previous tree unless result is fulfilled
        tree = result || tree
      })

      return lazyResult(render, tree)
    }

    // async mode
    let i = 0

    const next = (result, cb) => {
      _treeExtendApi(result, this)

      // all plugins called
      if (this.plugins.length <= i) {
        cb(null, result)
        return
      }

      // little helper to go to the next iteration
      function _next (res) {
        if (res && !options.skipParse) {
          res = [].concat(res)
        }

        return next(res || result, cb)
      }

      // call next
      const plugin = this.plugins[i++]

      if (plugin.length === 2) {
        plugin(result, (err, res) => {
          if (err) return cb(err)
          _next(res)
        })
        return
      }

      // sync and promised plugins
      let err = null

      const res = tryCatch(() => plugin(result), e => {
        err = e
        return e
      })

      if (err) {
        cb(err)
        return
      }

      if (isPromise(res)) {
        res.then(_next).catch(cb)
        return
      }

      _next(res)
    }

    return new Promise((resolve, reject) => {
      next(tree, (err, tree) => {
        if (err) reject(err)
        else resolve(lazyResult(render, tree))
      })
    })
  }
}

/**
 * @exports posthtml
 *
 * @param  {Array} plugins
 * @return {Function} posthtml
 *
 * **Usage**
 * ```js
 * import posthtml from 'posthtml'
 * import plugin from 'posthtml-plugin'
 *
 * const ph = posthtml([ plugin() ])
 * ```
 */
module.exports = plugins => new PostHTML(plugins)

/**
 * Extension of options tree
 *
 * @private
 *
 * @param   {Array}    tree
 * @param   {Object}   PostHTML
 * @returns {?*}
 */
function _treeExtendApi (t, _t) {
  if (typeof t === 'object') {
    t = Object.assign(t, _t)
  }
}

/**
 * Checks if parameter is a Promise (or thenable) object.
 *
 * @private
 *
 * @param   {*} promise - Target `{}` to test
 * @returns {Boolean}
 */
function isPromise (promise) {
  return !!promise && typeof promise.then === 'function'
}

/**
 * Simple try/catch helper, if exists, returns result
 *
 * @private
 *
 * @param   {Function} tryFn - try block
 * @param   {Function} catchFn - catch block
 * @returns {?*}
 */
function tryCatch (tryFn, catchFn) {
  try {
    return tryFn()
  } catch (err) {
    catchFn(err)
  }
}

/**
 * Wraps the PostHTMLTree within an object using a getter to render HTML on demand.
 *
 * @private
 *
 * @param   {Function} render
 * @param   {Array}    tree
 * @returns {Object<{html: String, tree: Array}>}
 */
function lazyResult (render, tree) {
  return {
    get html () {
      return render(tree, tree.options)
    },
    tree,
    messages: tree.messages
  }
}