Initial commit

src/js/operations/Unicode.js

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+/**
+ * Unicode operations.
+ *
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2016
+ * @license Apache-2.0
+ *
+ * @namespace
+ */
+var Unicode = {
+
+    /**
+     * @constant
+     * @default
+     */
+    PREFIXES: ["\\u", "%u", "U+"],
+
+    /**
+     * Unescape Unicode Characters operation.
+     *
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run_unescape: function(input, args) {
+        var prefix = Unicode._prefix_to_regex[args[0]],
+            regex = new RegExp(prefix+"([a-f\\d]{4,6})", "ig"),
+            output = "",
+            m,
+            i = 0;
+        
+        while (!!(m = regex.exec(input))) {
+            // Add up to match
+            output += input.slice(i, m.index);
+            i = m.index;
+            
+            // Add match
+            output += Utils.chr(parseInt(m[1], 16));
+            
+            i = regex.lastIndex;
+        }
+        
+        // Add all after final match
+        output += input.slice(i, input.length);
+        
+        return output;
+    },
+    
+    
+    /**
+     * Lookup table to add prefixes to unicode delimiters so that they can be used in a regex.
+     *
+     * @private
+     * @constant
+     */
+    _prefix_to_regex: {
+        "\\u": "\\\\u",
+        "%u": "%u",
+        "U+": "U\\+"
+    },
+
+};