| // Copyright 2014 Google Inc. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| (function(scope, testing) { |
| |
| // Evaluates a calc expression. |
| // https://drafts.csswg.org/css-values-3/#calc-notation |
| function calculate(expression) { |
| // In calc expressions, white space is required on both sides of the |
| // + and - operators. https://drafts.csswg.org/css-values-3/#calc-notation |
| // Thus any + or - immediately adjacent to . or 0..9 is part of the number, |
| // e.g. -1.23e+45 |
| // This regular expression matches ( ) * / + - and numbers. |
| var tokenRegularExpression = /([\+\-\w\.]+|[\(\)\*\/])/g; |
| var currentToken; |
| function consume() { |
| var matchResult = tokenRegularExpression.exec(expression); |
| if (matchResult) |
| currentToken = matchResult[0]; |
| else |
| currentToken = undefined; |
| } |
| consume(); // Read the initial token. |
| |
| function calcNumber() { |
| // https://drafts.csswg.org/css-values-3/#number-value |
| var result = Number(currentToken); |
| consume(); |
| return result; |
| } |
| |
| function calcValue() { |
| // <calc-value> = <number> | <dimension> | <percentage> | ( <calc-sum> ) |
| if (currentToken !== '(') |
| return calcNumber(); |
| consume(); |
| var result = calcSum(); |
| if (currentToken !== ')') |
| return NaN; |
| consume(); |
| return result; |
| } |
| |
| function calcProduct() { |
| // <calc-product> = <calc-value> [ '*' <calc-value> | '/' <calc-number-value> ]* |
| var left = calcValue(); |
| while (currentToken === '*' || currentToken === '/') { |
| var operator = currentToken; |
| consume(); |
| var right = calcValue(); |
| if (operator === '*') |
| left *= right; |
| else |
| left /= right; |
| } |
| return left; |
| } |
| |
| function calcSum() { |
| // <calc-sum> = <calc-product> [ [ '+' | '-' ] <calc-product> ]* |
| var left = calcProduct(); |
| while (currentToken === '+' || currentToken === '-') { |
| var operator = currentToken; |
| consume(); |
| var right = calcProduct(); |
| if (operator === '+') |
| left += right; |
| else |
| left -= right; |
| } |
| return left; |
| } |
| |
| // <calc()> = calc( <calc-sum> ) |
| return calcSum(); |
| } |
| |
| function parseDimension(unitRegExp, string) { |
| string = string.trim().toLowerCase(); |
| |
| if (string == '0' && 'px'.search(unitRegExp) >= 0) |
| return {px: 0}; |
| |
| // If we have parenthesis, we're a calc and need to start with 'calc'. |
| if (!/^[^(]*$|^calc/.test(string)) |
| return; |
| string = string.replace(/calc\(/g, '('); |
| |
| // We tag units by prefixing them with 'U' (note that we are already |
| // lowercase) to prevent problems with types which are substrings of |
| // each other (although prefixes may be problematic!) |
| var matchedUnits = {}; |
| string = string.replace(unitRegExp, function(match) { |
| matchedUnits[match] = null; |
| return 'U' + match; |
| }); |
| var taggedUnitRegExp = 'U(' + unitRegExp.source + ')'; |
| |
| // Validating input is simply applying as many reductions as we can. |
| var typeCheck = string.replace(/[-+]?(\d*\.)?\d+([Ee][-+]?\d+)?/g, 'N') |
| .replace(new RegExp('N' + taggedUnitRegExp, 'g'), 'D') |
| .replace(/\s[+-]\s/g, 'O') |
| .replace(/\s/g, ''); |
| var reductions = [/N\*(D)/g, /(N|D)[*/]N/g, /(N|D)O\1/g, /\((N|D)\)/g]; |
| var i = 0; |
| while (i < reductions.length) { |
| if (reductions[i].test(typeCheck)) { |
| typeCheck = typeCheck.replace(reductions[i], '$1'); |
| i = 0; |
| } else { |
| i++; |
| } |
| } |
| if (typeCheck != 'D') |
| return; |
| |
| for (var unit in matchedUnits) { |
| var result = calculate(string.replace(new RegExp('U' + unit, 'g'), '').replace(new RegExp(taggedUnitRegExp, 'g'), '*0')); |
| if (!isFinite(result)) |
| return; |
| matchedUnits[unit] = result; |
| } |
| return matchedUnits; |
| } |
| |
| function mergeDimensionsNonNegative(left, right) { |
| return mergeDimensions(left, right, true); |
| } |
| |
| function mergeDimensions(left, right, nonNegative) { |
| var units = [], unit; |
| for (unit in left) |
| units.push(unit); |
| for (unit in right) { |
| if (units.indexOf(unit) < 0) |
| units.push(unit); |
| } |
| |
| left = units.map(function(unit) { return left[unit] || 0; }); |
| right = units.map(function(unit) { return right[unit] || 0; }); |
| return [left, right, function(values) { |
| var result = values.map(function(value, i) { |
| if (values.length == 1 && nonNegative) { |
| value = Math.max(value, 0); |
| } |
| // Scientific notation (e.g. 1e2) is not yet widely supported by browser vendors. |
| return scope.numberToString(value) + units[i]; |
| }).join(' + '); |
| return values.length > 1 ? 'calc(' + result + ')' : result; |
| }]; |
| } |
| |
| var lengthUnits = 'px|em|ex|ch|rem|vw|vh|vmin|vmax|cm|mm|in|pt|pc'; |
| var parseLength = parseDimension.bind(null, new RegExp(lengthUnits, 'g')); |
| var parseLengthOrPercent = parseDimension.bind(null, new RegExp(lengthUnits + '|%', 'g')); |
| var parseAngle = parseDimension.bind(null, /deg|rad|grad|turn/g); |
| |
| scope.parseLength = parseLength; |
| scope.parseLengthOrPercent = parseLengthOrPercent; |
| scope.consumeLengthOrPercent = scope.consumeParenthesised.bind(null, parseLengthOrPercent); |
| scope.parseAngle = parseAngle; |
| scope.mergeDimensions = mergeDimensions; |
| |
| var consumeLength = scope.consumeParenthesised.bind(null, parseLength); |
| var consumeSizePair = scope.consumeRepeated.bind(undefined, consumeLength, /^/); |
| var consumeSizePairList = scope.consumeRepeated.bind(undefined, consumeSizePair, /^,/); |
| scope.consumeSizePairList = consumeSizePairList; |
| |
| var parseSizePairList = function(input) { |
| var result = consumeSizePairList(input); |
| if (result && result[1] == '') { |
| return result[0]; |
| } |
| }; |
| |
| var mergeNonNegativeSizePair = scope.mergeNestedRepeated.bind(undefined, mergeDimensionsNonNegative, ' '); |
| var mergeNonNegativeSizePairList = scope.mergeNestedRepeated.bind(undefined, mergeNonNegativeSizePair, ','); |
| scope.mergeNonNegativeSizePair = mergeNonNegativeSizePair; |
| |
| scope.addPropertiesHandler(parseSizePairList, mergeNonNegativeSizePairList, [ |
| 'background-size' |
| ]); |
| |
| scope.addPropertiesHandler(parseLengthOrPercent, mergeDimensionsNonNegative, [ |
| 'border-bottom-width', |
| 'border-image-width', |
| 'border-left-width', |
| 'border-right-width', |
| 'border-top-width', |
| 'flex-basis', |
| 'font-size', |
| 'height', |
| 'line-height', |
| 'max-height', |
| 'max-width', |
| 'outline-width', |
| 'width', |
| ]); |
| |
| scope.addPropertiesHandler(parseLengthOrPercent, mergeDimensions, [ |
| 'border-bottom-left-radius', |
| 'border-bottom-right-radius', |
| 'border-top-left-radius', |
| 'border-top-right-radius', |
| 'bottom', |
| 'left', |
| 'letter-spacing', |
| 'margin-bottom', |
| 'margin-left', |
| 'margin-right', |
| 'margin-top', |
| 'min-height', |
| 'min-width', |
| 'outline-offset', |
| 'padding-bottom', |
| 'padding-left', |
| 'padding-right', |
| 'padding-top', |
| 'perspective', |
| 'right', |
| 'shape-margin', |
| 'stroke-dashoffset', |
| 'text-indent', |
| 'top', |
| 'vertical-align', |
| 'word-spacing', |
| ]); |
| |
| })(webAnimations1, webAnimationsTesting); |