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+/* 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 module provides the PluralForm object which contains a method to figure
+ * out which plural form of a word to use for a given number based on the
+ * current localization. There is also a makeGetter method that creates a get
+ * function for the desired plural rule. This is useful for extensions that
+ * specify their own plural rule instead of relying on the browser default.
+ * (I.e., the extension hasn't been localized to the browser's locale.)
+ *
+ * See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+ *
+ * NOTE: any change to these plural forms need to be reflected in
+ * compare-locales:
+ * https://hg.mozilla.org/l10n/compare-locales/file/default/compare_locales/plurals.py
+ *
+ * List of methods:
+ *
+ * string pluralForm
+ * get(int aNum, string aWords)
+ *
+ * int numForms
+ * numForms()
+ *
+ * [string pluralForm get(int aNum, string aWords), int numForms numForms()]
+ * makeGetter(int aRuleNum)
+ * Note: Basically, makeGetter returns 2 functions that do "get" and "numForm"
+ */
+
+const kIntlProperties = "chrome://global/locale/intl.properties";
+
+// These are the available plural functions that give the appropriate index
+// based on the plural rule number specified. The first element is the number
+// of plural forms and the second is the function to figure out the index.
+/* eslint-disable no-nested-ternary */
+var gFunctions = [
+ // 0: Chinese
+ [1, n => 0],
+ // 1: English
+ [2, n => (n != 1 ? 1 : 0)],
+ // 2: French
+ [2, n => (n > 1 ? 1 : 0)],
+ // 3: Latvian
+ [3, n => (n % 10 == 1 && n % 100 != 11 ? 1 : n % 10 == 0 ? 0 : 2)],
+ // 4: Scottish Gaelic
+ [
+ 4,
+ n =>
+ n == 1 || n == 11 ? 0 : n == 2 || n == 12 ? 1 : n > 0 && n < 20 ? 2 : 3,
+ ],
+ // 5: Romanian
+ [3, n => (n == 1 ? 0 : n == 0 || (n % 100 > 0 && n % 100 < 20) ? 1 : 2)],
+ // 6: Lithuanian
+ [
+ 3,
+ n =>
+ n % 10 == 1 && n % 100 != 11
+ ? 0
+ : n % 10 >= 2 && (n % 100 < 10 || n % 100 >= 20)
+ ? 2
+ : 1,
+ ],
+ // 7: Russian
+ [
+ 3,
+ n =>
+ n % 10 == 1 && n % 100 != 11
+ ? 0
+ : n % 10 >= 2 && n % 10 <= 4 && (n % 100 < 10 || n % 100 >= 20)
+ ? 1
+ : 2,
+ ],
+ // 8: Slovak
+ [3, n => (n == 1 ? 0 : n >= 2 && n <= 4 ? 1 : 2)],
+ // 9: Polish
+ [
+ 3,
+ n =>
+ n == 1
+ ? 0
+ : n % 10 >= 2 && n % 10 <= 4 && (n % 100 < 10 || n % 100 >= 20)
+ ? 1
+ : 2,
+ ],
+ // 10: Slovenian
+ [
+ 4,
+ n =>
+ n % 100 == 1
+ ? 0
+ : n % 100 == 2
+ ? 1
+ : n % 100 == 3 || n % 100 == 4
+ ? 2
+ : 3,
+ ],
+ // 11: Irish Gaeilge
+ [
+ 5,
+ n =>
+ n == 1
+ ? 0
+ : n == 2
+ ? 1
+ : n >= 3 && n <= 6
+ ? 2
+ : n >= 7 && n <= 10
+ ? 3
+ : 4,
+ ],
+ // 12: Arabic
+ [
+ 6,
+ n =>
+ n == 0
+ ? 5
+ : n == 1
+ ? 0
+ : n == 2
+ ? 1
+ : n % 100 >= 3 && n % 100 <= 10
+ ? 2
+ : n % 100 >= 11 && n % 100 <= 99
+ ? 3
+ : 4,
+ ],
+ // 13: Maltese
+ [
+ 4,
+ n =>
+ n == 1
+ ? 0
+ : n == 0 || (n % 100 > 0 && n % 100 <= 10)
+ ? 1
+ : n % 100 > 10 && n % 100 < 20
+ ? 2
+ : 3,
+ ],
+ // 14: Unused
+ [3, n => (n % 10 == 1 ? 0 : n % 10 == 2 ? 1 : 2)],
+ // 15: Icelandic, Macedonian
+ [2, n => (n % 10 == 1 && n % 100 != 11 ? 0 : 1)],
+ // 16: Breton
+ [
+ 5,
+ n =>
+ n % 10 == 1 && n % 100 != 11 && n % 100 != 71 && n % 100 != 91
+ ? 0
+ : n % 10 == 2 && n % 100 != 12 && n % 100 != 72 && n % 100 != 92
+ ? 1
+ : (n % 10 == 3 || n % 10 == 4 || n % 10 == 9) &&
+ n % 100 != 13 &&
+ n % 100 != 14 &&
+ n % 100 != 19 &&
+ n % 100 != 73 &&
+ n % 100 != 74 &&
+ n % 100 != 79 &&
+ n % 100 != 93 &&
+ n % 100 != 94 &&
+ n % 100 != 99
+ ? 2
+ : n % 1000000 == 0 && n != 0
+ ? 3
+ : 4,
+ ],
+ // 17: Shuar
+ [2, n => (n != 0 ? 1 : 0)],
+ // 18: Welsh
+ [
+ 6,
+ n => (n == 0 ? 0 : n == 1 ? 1 : n == 2 ? 2 : n == 3 ? 3 : n == 6 ? 4 : 5),
+ ],
+ // 19: Slavic languages (bs, hr, sr). Same as rule 7, but resulting in different CLDR categories
+ [
+ 3,
+ n =>
+ n % 10 == 1 && n % 100 != 11
+ ? 0
+ : n % 10 >= 2 && n % 10 <= 4 && (n % 100 < 10 || n % 100 >= 20)
+ ? 1
+ : 2,
+ ],
+];
+
+/* eslint-enable no-nested-ternary */
+
+export var PluralForm = {
+ /**
+ * Get the correct plural form of a word based on the number
+ *
+ * @param aNum
+ * The number to decide which plural form to use
+ * @param aWords
+ * A semi-colon (;) separated string of words to pick the plural form
+ * @return The appropriate plural form of the word
+ */
+ get get() {
+ // This method will lazily load to avoid perf when it is first needed and
+ // creates getPluralForm function. The function it creates is based on the
+ // value of pluralRule specified in the intl stringbundle.
+ // See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+
+ // Delete the getters to be overwritten
+ delete PluralForm.numForms;
+ delete PluralForm.get;
+
+ // Make the plural form get function and set it as the default get
+ [PluralForm.get, PluralForm.numForms] = PluralForm.makeGetter(
+ PluralForm.ruleNum
+ );
+ return PluralForm.get;
+ },
+
+ /**
+ * Create a pair of plural form functions for the given plural rule number.
+ *
+ * @param aRuleNum
+ * The plural rule number to create functions
+ * @return A pair: [function that gets the right plural form,
+ * function that returns the number of plural forms]
+ */
+ makeGetter(aRuleNum) {
+ // Default to "all plural" if the value is out of bounds or invalid
+ if (aRuleNum < 0 || aRuleNum >= gFunctions.length || isNaN(aRuleNum)) {
+ log(["Invalid rule number: ", aRuleNum, " -- defaulting to 0"]);
+ aRuleNum = 0;
+ }
+
+ // Get the desired pluralRule function
+ let [numForms, pluralFunc] = gFunctions[aRuleNum];
+
+ // Return functions that give 1) the number of forms and 2) gets the right
+ // plural form
+ return [
+ function (aNum, aWords) {
+ // Figure out which index to use for the semi-colon separated words
+ let index = pluralFunc(aNum ? Number(aNum) : 0);
+ let words = aWords ? aWords.split(/;/) : [""];
+
+ // Explicitly check bounds to avoid strict warnings
+ let ret = index < words.length ? words[index] : undefined;
+
+ // Check for array out of bounds or empty strings
+ if (ret == undefined || ret == "") {
+ // Report the caller to help figure out who is causing badness
+ let caller = Components.stack.caller
+ ? Components.stack.caller.name
+ : "top";
+
+ // Display a message in the error console
+ log([
+ "Index #",
+ index,
+ " of '",
+ aWords,
+ "' for value ",
+ aNum,
+ " is invalid -- plural rule #",
+ aRuleNum,
+ "; called by ",
+ caller,
+ ]);
+
+ // Default to the first entry (which might be empty, but not undefined)
+ ret = words[0];
+ }
+
+ return ret;
+ },
+ () => numForms,
+ ];
+ },
+
+ /**
+ * Get the number of forms for the current plural rule
+ *
+ * @return The number of forms
+ */
+ get numForms() {
+ // We lazily load numForms, so trigger the init logic with get()
+ PluralForm.get();
+ return PluralForm.numForms;
+ },
+
+ /**
+ * Get the plural rule number from the intl stringbundle
+ *
+ * @return The plural rule number
+ */
+ get ruleNum() {
+ return Number(
+ Services.strings
+ .createBundle(kIntlProperties)
+ .GetStringFromName("pluralRule")
+ );
+ },
+};
+
+/**
+ * Private helper function to log errors to the error console and command line
+ *
+ * @param aMsg
+ * Error message to log or an array of strings to concat
+ */
+function log(aMsg) {
+ let msg = "PluralForm.jsm: " + (aMsg.join ? aMsg.join("") : aMsg);
+ Services.console.logStringMessage(msg);
+ dump(msg + "\n");
+}