first commit

build/node_modules/css-tree/lib/lexer/generic.js

@@ -0,0 +1,221 @@
+'use strict';
+
+var names = require('../utils/names.js');
+
+// https://www.w3.org/TR/css-values-3/#lengths
+var LENGTH = {
+    // absolute length units
+    'px': true,
+    'mm': true,
+    'cm': true,
+    'in': true,
+    'pt': true,
+    'pc': true,
+    'q': true,
+
+    // relative length units
+    'em': true,
+    'ex': true,
+    'ch': true,
+    'rem': true,
+
+    // viewport-percentage lengths
+    'vh': true,
+    'vw': true,
+    'vmin': true,
+    'vmax': true,
+    'vm': true
+};
+
+var ANGLE = {
+    'deg': true,
+    'grad': true,
+    'rad': true,
+    'turn': true
+};
+
+var TIME = {
+    's': true,
+    'ms': true
+};
+
+var FREQUENCY = {
+    'hz': true,
+    'khz': true
+};
+
+// https://www.w3.org/TR/css-values-3/#resolution (https://drafts.csswg.org/css-values/#resolution)
+var RESOLUTION = {
+    'dpi': true,
+    'dpcm': true,
+    'dppx': true,
+    'x': true      // https://github.com/w3c/csswg-drafts/issues/461
+};
+
+// https://drafts.csswg.org/css-grid/#fr-unit
+var FLEX = {
+    'fr': true
+};
+
+// https://www.w3.org/TR/css3-speech/#mixing-props-voice-volume
+var DECIBEL = {
+    'db': true
+};
+
+// https://www.w3.org/TR/css3-speech/#voice-props-voice-pitch
+var SEMITONES = {
+    'st': true
+};
+
+// can be used wherever <length>, <frequency>, <angle>, <time>, <percentage>, <number>, or <integer> values are allowed
+// https://drafts.csswg.org/css-values/#calc-notation
+function isCalc(node) {
+    if (node.data.type !== 'Function') {
+        return false;
+    }
+
+    var keyword = names.keyword(node.data.name);
+
+    if (keyword.name !== 'calc') {
+        return false;
+    }
+
+    // there were some prefixed implementations
+    return keyword.vendor === '' ||
+           keyword.vendor === '-moz-' ||
+           keyword.vendor === '-webkit-';
+}
+
+function astNode(type) {
+    return function(node) {
+        return node.data.type === type;
+    };
+}
+
+function dimension(type) {
+    return function(node) {
+        return isCalc(node) ||
+               (node.data.type === 'Dimension' && type.hasOwnProperty(node.data.unit.toLowerCase()));
+    };
+}
+
+function zeroUnitlessDimension(type) {
+    return function(node) {
+        return isCalc(node) ||
+               (node.data.type === 'Dimension' && type.hasOwnProperty(node.data.unit.toLowerCase())) ||
+               (node.data.type === 'Number' && Number(node.data.value) === 0);
+    };
+}
+
+function attr(node) {
+    return node.data.type === 'Function' && node.data.name.toLowerCase() === 'attr';
+}
+
+function number(node) {
+    return isCalc(node) || node.data.type === 'Number';
+}
+
+function numberZeroOne(node) {
+    if (isCalc(node) || node.data.type === 'Number') {
+        var value = Number(node.data.value);
+
+        return value >= 0 && value <= 1;
+    }
+
+    return false;
+}
+
+function numberOneOrGreater(node) {
+    if (isCalc(node) || node.data.type === 'Number') {
+        return Number(node.data.value) >= 1;
+    }
+
+    return false;
+}
+
+// TODO: fail on 10e-2
+function integer(node) {
+    return isCalc(node) ||
+           (node.data.type === 'Number' && node.data.value.indexOf('.') === -1);
+}
+
+// TODO: fail on 10e-2
+function positiveInteger(node) {
+    return isCalc(node) ||
+           (node.data.type === 'Number' && node.data.value.indexOf('.') === -1 && node.data.value.charAt(0) !== '-');
+}
+
+function percentage(node) {
+    return isCalc(node) ||
+           node.data.type === 'Percentage';
+}
+
+function hexColor(node) {
+    if (node.data.type !== 'HexColor') {
+        return false;
+    }
+
+    var hex = node.data.value;
+
+    return /^[0-9a-fA-F]{3,8}$/.test(hex) &&
+           (hex.length === 3 || hex.length === 4 || hex.length === 6 || hex.length === 8);
+}
+
+function expression(node) {
+    return node.data.type === 'Function' && node.data.name.toLowerCase() === 'expression';
+}
+
+// https://developer.mozilla.org/en-US/docs/Web/CSS/custom-ident
+// https://drafts.csswg.org/css-values-4/#identifier-value
+function customIdent(node) {
+    if (node.data.type !== 'Identifier') {
+        return false;
+    }
+
+    var name = node.data.name.toLowerCase();
+
+    // § 3.2. Author-defined Identifiers: the <custom-ident> type
+    // The CSS-wide keywords are not valid <custom-ident>s
+    if (name === 'unset' || name === 'initial' || name === 'inherit') {
+        return false;
+    }
+
+    // The default keyword is reserved and is also not a valid <custom-ident>
+    if (name === 'default') {
+        return false;
+    }
+
+    // TODO: ignore property specific keywords (as described https://developer.mozilla.org/en-US/docs/Web/CSS/custom-ident)
+
+    return true;
+}
+
+module.exports = {
+    'angle': zeroUnitlessDimension(ANGLE),
+    'attr()': attr,
+    'custom-ident': customIdent,
+    'decibel': dimension(DECIBEL),
+    'dimension': astNode('Dimension'),
+    'frequency': dimension(FREQUENCY),
+    'flex': dimension(FLEX),
+    'hex-color': hexColor,
+    'id-selector': astNode('IdSelector'), // element( <id-selector> )
+    'ident': astNode('Identifier'),
+    'integer': integer,
+    'length': zeroUnitlessDimension(LENGTH),
+    'number': number,
+    'number-zero-one': numberZeroOne,
+    'number-one-or-greater': numberOneOrGreater,
+    'percentage': percentage,
+    'positive-integer': positiveInteger,
+    'resolution': dimension(RESOLUTION),
+    'semitones': dimension(SEMITONES),
+    'string': astNode('String'),
+    'time': dimension(TIME),
+    'unicode-range': astNode('UnicodeRange'),
+    'url': astNode('Url'),
+
+    // old IE stuff
+    'progid': astNode('Raw'),
+    'expression': expression
+};