time-to-botec

Benchmark sampling in different programming languages
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days_in_month.js (3318B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var isDateObject = require( '@stdlib/assert/is-date-object' );
     24 var isString = require( '@stdlib/assert/is-string' ).isPrimitive;
     25 var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
     26 var lowercase = require( '@stdlib/string/lowercase' );
     27 var isLeapYear = require( '@stdlib/assert/is-leap-year' );
     28 var DAYS_IN_MONTH = require( './days.json' );
     29 
     30 
     31 // MAIN //
     32 
     33 /**
     34 * Returns the number of days in a month.
     35 *
     36 * @param {(string|Date|integer)} [month] - month (or Date)
     37 * @param {integer} [year] - year
     38 * @throws {TypeError} first argument must be either a string, integer, or `Date` object
     39 * @throws {Error} must provide a recognized month
     40 * @throws {RangeError} an integer month argument must be on the interval `[1,12]`
     41 * @throws {TypeError} second argument must be an integer
     42 * @returns {integer} days in a month
     43 *
     44 * @example
     45 * var num = daysInMonth();
     46 * // returns <number>
     47 *
     48 * @example
     49 * var num = daysInMonth( 2 );
     50 * // returns <number>
     51 *
     52 * @example
     53 * var num = daysInMonth( 2, 2016 );
     54 * // returns 29
     55 *
     56 * @example
     57 * var num = daysInMonth( 2, 2017 );
     58 * // returns 28
     59 */
     60 function daysInMonth( month, year ) {
     61 	var days;
     62 	var mon;
     63 	var yr;
     64 	var d;
     65 	if ( arguments.length === 0 ) {
     66 		// Note: cannot cache as application may cross over into a new year:
     67 		d = new Date();
     68 		mon = d.getMonth() + 1; // zero-based
     69 		yr = d.getFullYear();
     70 	} else if ( arguments.length === 1 ) {
     71 		if ( isDateObject( month ) ) {
     72 			d = month;
     73 			mon = d.getMonth() + 1; // zero-based
     74 			yr = d.getFullYear();
     75 		} else if ( isString( month ) || isInteger( month ) ) {
     76 			// Note: cannot cache as application may cross over into a new year:
     77 			yr = ( new Date() ).getFullYear();
     78 			mon = month;
     79 		} else {
     80 			throw new TypeError( 'invalid argument. First argument must be either a string, integer, or `Date` object. Value: `'+month+'`.' );
     81 		}
     82 	} else {
     83 		if ( !isString( month ) && !isInteger( month ) ) {
     84 			throw new TypeError( 'invalid argument. First argument must be either a string or integer. Value: `'+month+'`.' );
     85 		}
     86 		if ( !isInteger( year ) ) {
     87 			throw new TypeError( 'invalid argument. Second argument must be an integer. Value: `'+year+'`.' );
     88 		}
     89 		mon = month;
     90 		yr = year;
     91 	}
     92 	if ( isInteger( mon ) && (mon < 1 || mon > 12) ) {
     93 		throw new RangeError( 'invalid argument. An integer month value must be on the interval `[1,12]`. Value: `'+mon+'`.' );
     94 	}
     95 	mon = lowercase( mon.toString() );
     96 	days = DAYS_IN_MONTH[ mon ];
     97 	if ( days === void 0 ) {
     98 		throw new Error( 'invalid argument. Must provide a recognized month. Value: `'+mon+'`.' );
     99 	}
    100 	if ( days === 28 && isLeapYear( yr ) ) {
    101 		days += 1;
    102 	}
    103 	return days;
    104 }
    105 
    106 
    107 // EXPORTS //
    108 
    109 module.exports = daysInMonth;