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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/. */
var EXPORTED_SYMBOLS = ["PluralForm"];
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
/**
* 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.)
*
*
* NOTE: any change to these plural forms need to be reflected in
* compare-locales:
*
* 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 */
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.
// 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");
}