aboutsummaryrefslogtreecommitdiff
path: root/node_modules/fbjs/lib/UnicodeBidiService.js
diff options
context:
space:
mode:
Diffstat (limited to 'node_modules/fbjs/lib/UnicodeBidiService.js')
-rw-r--r--node_modules/fbjs/lib/UnicodeBidiService.js100
1 files changed, 100 insertions, 0 deletions
diff --git a/node_modules/fbjs/lib/UnicodeBidiService.js b/node_modules/fbjs/lib/UnicodeBidiService.js
new file mode 100644
index 000000000..f7189d8ee
--- /dev/null
+++ b/node_modules/fbjs/lib/UnicodeBidiService.js
@@ -0,0 +1,100 @@
+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @typechecks
+ *
+ */
+
+/**
+ * Stateful API for text direction detection
+ *
+ * This class can be used in applications where you need to detect the
+ * direction of a sequence of text blocks, where each direction shall be used
+ * as the fallback direction for the next one.
+ *
+ * NOTE: A default direction, if not provided, is set based on the global
+ * direction, as defined by `UnicodeBidiDirection`.
+ *
+ * == Example ==
+ * ```
+ * var UnicodeBidiService = require('UnicodeBidiService');
+ *
+ * var bidiService = new UnicodeBidiService();
+ *
+ * ...
+ *
+ * bidiService.reset();
+ * for (var para in paragraphs) {
+ * var dir = bidiService.getDirection(para);
+ * ...
+ * }
+ * ```
+ *
+ * Part of our implementation of Unicode Bidirectional Algorithm (UBA)
+ * Unicode Standard Annex #9 (UAX9)
+ * http://www.unicode.org/reports/tr9/
+ */
+
+'use strict';
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var UnicodeBidi = require('./UnicodeBidi');
+var UnicodeBidiDirection = require('./UnicodeBidiDirection');
+
+var invariant = require('./invariant');
+
+var UnicodeBidiService = function () {
+
+ /**
+ * Stateful class for paragraph direction detection
+ *
+ * @param defaultDir Default direction of the service
+ */
+ function UnicodeBidiService(defaultDir) {
+ _classCallCheck(this, UnicodeBidiService);
+
+ if (!defaultDir) {
+ defaultDir = UnicodeBidiDirection.getGlobalDir();
+ } else {
+ !UnicodeBidiDirection.isStrong(defaultDir) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'Default direction must be a strong direction (LTR or RTL)') : invariant(false) : void 0;
+ }
+ this._defaultDir = defaultDir;
+ this.reset();
+ }
+
+ /**
+ * Reset the internal state
+ *
+ * Instead of creating a new instance, you can just reset() your instance
+ * everytime you start a new loop.
+ */
+
+
+ UnicodeBidiService.prototype.reset = function reset() {
+ this._lastDir = this._defaultDir;
+ };
+
+ /**
+ * Returns the direction of a block of text, and remembers it as the
+ * fall-back direction for the next paragraph.
+ *
+ * @param str A text block, e.g. paragraph, table cell, tag
+ * @return The resolved direction
+ */
+
+
+ UnicodeBidiService.prototype.getDirection = function getDirection(str) {
+ this._lastDir = UnicodeBidi.getDirection(str, this._lastDir);
+ return this._lastDir;
+ };
+
+ return UnicodeBidiService;
+}();
+
+module.exports = UnicodeBidiService; \ No newline at end of file