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Diffstat (limited to 'node_modules/locutus/php/strings/substr.js')
| -rw-r--r-- | node_modules/locutus/php/strings/substr.js | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/node_modules/locutus/php/strings/substr.js b/node_modules/locutus/php/strings/substr.js new file mode 100644 index 0000000..3498296 --- /dev/null +++ b/node_modules/locutus/php/strings/substr.js @@ -0,0 +1,124 @@ +'use strict'; + +module.exports = function substr(str, start, len) { + // discuss at: http://locutus.io/php/substr/ + // original by: Martijn Wieringa + // bugfixed by: T.Wild + // improved by: Onno Marsman (https://twitter.com/onnomarsman) + // improved by: Brett Zamir (http://brett-zamir.me) + // revised by: Theriault (https://github.com/Theriault) + // note 1: Handles rare Unicode characters if 'unicode.semantics' ini (PHP6) is set to 'on' + // example 1: substr('abcdef', 0, -1) + // returns 1: 'abcde' + // example 2: substr(2, 0, -6) + // returns 2: false + // example 3: ini_set('unicode.semantics', 'on') + // example 3: substr('a\uD801\uDC00', 0, -1) + // returns 3: 'a' + // example 4: ini_set('unicode.semantics', 'on') + // example 4: substr('a\uD801\uDC00', 0, 2) + // returns 4: 'a\uD801\uDC00' + // example 5: ini_set('unicode.semantics', 'on') + // example 5: substr('a\uD801\uDC00', -1, 1) + // returns 5: '\uD801\uDC00' + // example 6: ini_set('unicode.semantics', 'on') + // example 6: substr('a\uD801\uDC00z\uD801\uDC00', -3, 2) + // returns 6: '\uD801\uDC00z' + // example 7: ini_set('unicode.semantics', 'on') + // example 7: substr('a\uD801\uDC00z\uD801\uDC00', -3, -1) + // returns 7: '\uD801\uDC00z' + // test: skip-3 skip-4 skip-5 skip-6 skip-7 + + str += ''; + var end = str.length; + + var iniVal = (typeof require !== 'undefined' ? require('../info/ini_get')('unicode.emantics') : undefined) || 'off'; + + if (iniVal === 'off') { + // assumes there are no non-BMP characters; + // if there may be such characters, then it is best to turn it on (critical in true XHTML/XML) + if (start < 0) { + start += end; + } + if (typeof len !== 'undefined') { + if (len < 0) { + end = len + end; + } else { + end = len + start; + } + } + + // PHP returns false if start does not fall within the string. + // PHP returns false if the calculated end comes before the calculated start. + // PHP returns an empty string if start and end are the same. + // Otherwise, PHP returns the portion of the string from start to end. + if (start >= str.length || start < 0 || start > end) { + return false; + } + + return str.slice(start, end); + } + + // Full-blown Unicode including non-Basic-Multilingual-Plane characters + var i = 0; + var allBMP = true; + var es = 0; + var el = 0; + var se = 0; + var ret = ''; + + for (i = 0; i < str.length; i++) { + if (/[\uD800-\uDBFF]/.test(str.charAt(i)) && /[\uDC00-\uDFFF]/.test(str.charAt(i + 1))) { + allBMP = false; + break; + } + } + + if (!allBMP) { + if (start < 0) { + for (i = end - 1, es = start += end; i >= es; i--) { + if (/[\uDC00-\uDFFF]/.test(str.charAt(i)) && /[\uD800-\uDBFF]/.test(str.charAt(i - 1))) { + start--; + es--; + } + } + } else { + var surrogatePairs = /[\uD800-\uDBFF][\uDC00-\uDFFF]/g; + while (surrogatePairs.exec(str) !== null) { + var li = surrogatePairs.lastIndex; + if (li - 2 < start) { + start++; + } else { + break; + } + } + } + + if (start >= end || start < 0) { + return false; + } + if (len < 0) { + for (i = end - 1, el = end += len; i >= el; i--) { + if (/[\uDC00-\uDFFF]/.test(str.charAt(i)) && /[\uD800-\uDBFF]/.test(str.charAt(i - 1))) { + end--; + el--; + } + } + if (start > end) { + return false; + } + return str.slice(start, end); + } else { + se = start + len; + for (i = start; i < se; i++) { + ret += str.charAt(i); + if (/[\uD800-\uDBFF]/.test(str.charAt(i)) && /[\uDC00-\uDFFF]/.test(str.charAt(i + 1))) { + // Go one further, since one of the "characters" is part of a surrogate pair + se++; + } + } + return ret; + } + } +}; +//# sourceMappingURL=substr.js.map
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