Bug 731779: Integrate the Add-on SDK loader and API libraries into Firefox (uplifting from addon-sdk a16bbd5772880b578a939eeb65102bca6560d494)

addon-sdk/source/python-lib/plural-rules-generator.py

@@ -0,0 +1,176 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Program used to generate /packages/api-utils/lib/l10n/plural-rules.js
+# Fetch unicode.org data in order to build functions specific to each language
+# that will return for a given integer, its plural form name.
+# Plural form names are: zero, one, two, few, many, other.
+#
+# More information here:
+#   http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html
+#   http://cldr.unicode.org/index/cldr-spec/plural-rules
+
+# Usage:
+# $ python plural-rules-generator.py > ../packages/api-utils/lib/l10n/plural-rules.js
+
+import urllib2
+import xml.dom.minidom
+import json
+import re
+
+PRINT_CONDITIONS_IN_COMMENTS = False
+
+UNICODE_ORG_XML_URL = "http://unicode.org/repos/cldr/trunk/common/supplemental/plurals.xml"
+
+CONDITION_RE = r'n( mod \d+)? (is|in|within|(not in))( not)? ([^\s]+)'
+
+# For a given regexp.MatchObject `g` for `CONDITION_RE`, 
+# returns the equivalent JS piece of code
+# i.e. maps pseudo conditional language from unicode.org XML to JS code
+def parseCondition(g):
+    lvalue = "n"
+    if g.group(1):
+        lvalue = "(n %% %d)" % int(g.group(1).replace("mod ", ""))
+
+    operator = g.group(2)
+    if g.group(4):
+        operator += " not"
+
+    rvalue = g.group(5)
+
+    if operator == "is":
+        return "%s == %s" % (lvalue, rvalue)
+    if operator == "is not":
+        return "%s != %s" % (lvalue, rvalue)
+
+    # "in", "within" or "not in" case:
+    notPrefix = ""
+    if operator == "not in":
+        notPrefix = "!"
+
+    # `rvalue` is a comma seperated list of either:
+    #  - numbers: 42
+    #  - ranges: 42..72
+    sections = rvalue.split(',')
+
+    if ".." not in rvalue:
+        # If we don't have range, but only a list of integer,
+        # we can simplify the generated code by using `isIn`
+        # n in 1,3,6,42
+        return "%sisIn(%s, [%s])" % (notPrefix, lvalue, ", ".join(sections))
+
+    # n in 1..42
+    # n in 1..3,42
+    subCondition = []
+    integers = []
+    for sub in sections:
+        if ".." in sub:
+            left, right = sub.split("..")
+            subCondition.append("isBetween(%s, %d, %d)" % (
+                                lvalue,
+                                int(left),
+                                int(right)
+                               ))
+        else:
+            integers.append(int(sub))
+    if len(integers) > 1:
+      subCondition.append("isIn(%s, [%s])" % (lvalue, ", ".join(integers)))
+    elif len(integers) == 1:
+      subCondition.append("(%s == %s)" % (lvalue, integers[0]))
+    return "%s(%s)" % (notPrefix, " || ".join(subCondition))
+
+def computeRules():
+    # Fetch plural rules data directly from unicode.org website:
+    url = UNICODE_ORG_XML_URL
+    f = urllib2.urlopen(url)
+    doc = xml.dom.minidom.parse(f)
+
+    # Read XML document and extract locale to rules mapping
+    localesMapping = {}
+    algorithms = {}
+    for index,pluralRules in enumerate(doc.getElementsByTagName("pluralRules")):
+        if not index in algorithms:
+            algorithms[index] = {}
+        for locale in pluralRules.getAttribute("locales").split():
+            localesMapping[locale] = index
+        for rule in pluralRules.childNodes:
+            if rule.nodeType != rule.ELEMENT_NODE or rule.tagName != "pluralRule":
+                continue
+            pluralForm = rule.getAttribute("count")
+            algorithm = rule.firstChild.nodeValue
+            algorithms[index][pluralForm] = algorithm
+
+    # Go through all rules and compute a Javascript code for each of them
+    rules = {}
+    for index,rule in algorithms.iteritems():
+        lines = []
+        for pluralForm in rule:
+            condition = rule[pluralForm]
+            originalCondition = str(condition)
+
+            # Convert pseudo language to JS code
+            condition = rule[pluralForm].lower()
+            condition = re.sub(CONDITION_RE, parseCondition, condition)
+            condition = re.sub(r'or', "||", condition)
+            condition = re.sub(r'and', "&&", condition)
+
+            # Prints original condition in unicode.org pseudo language
+            if PRINT_CONDITIONS_IN_COMMENTS:
+                lines.append( '// %s' % originalCondition )
+
+            lines.append( 'if (%s)' % condition )
+            lines.append( '  return "%s";' % pluralForm )
+            
+        rules[index] = "\n    ".join(lines)
+    return localesMapping, rules
+
+
+localesMapping, rules = computeRules()
+
+rulesLines = []
+for index in rules:
+    lines = rules[index]
+    rulesLines.append('"%d": function (n) {' % index)
+    rulesLines.append('  %s' % lines)
+    rulesLines.append('  return "other"')
+    rulesLines.append('},')
+
+print """/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This file is automatically generated with /python-lib/plural-rules-generator.py
+// Fetching data from: %s
+
+// Mapping of short locale name == to == > rule index in following list
+const LOCALES_TO_RULES = %s;
+
+// Utility functions for plural rules methods
+function isIn(n, list) list.indexOf(n) !== -1;
+function isBetween(n, start, end) start <= n && n <= end;
+
+// List of all plural rules methods, that maps an integer to the plural form name to use
+const RULES = {
+  %s
+};
+
+/**
+  * Return a function that gives the plural form name for a given integer
+  * for the specified `locale`
+  *   let fun = getRulesForLocale('en');
+  *   fun(1)    -> 'one'
+  *   fun(0)    -> 'other'
+  *   fun(1000) -> 'other'
+  */
+exports.getRulesForLocale = function getRulesForLocale(locale) {
+  let index = LOCALES_TO_RULES[locale];
+  if (!(index in RULES)) {
+    console.warn('Plural form unknown for locale "' + locale + '"');
+    return function () { return "other"; };
+  }
+  return RULES[index];
+}
+""" % (UNICODE_ORG_XML_URL,
+        json.dumps(localesMapping, sort_keys=True, indent=2),
+        "\n  ".join(rulesLines))