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diff --git a/node_modules/postcss-value-parser/README.md b/node_modules/postcss-value-parser/README.md new file mode 100644 index 0000000..3bd6a0d --- /dev/null +++ b/node_modules/postcss-value-parser/README.md @@ -0,0 +1,263 @@ +# postcss-value-parser + +[](https://travis-ci.org/TrySound/postcss-value-parser) + +Transforms CSS declaration values and at-rule parameters into a tree of nodes, and provides a simple traversal API. + +## Usage + +```js +var valueParser = require('postcss-value-parser'); +var cssBackgroundValue = 'url(foo.png) no-repeat 40px 73%'; +var parsedValue = valueParser(cssBackgroundValue); +// parsedValue exposes an API described below, +// e.g. parsedValue.walk(..), parsedValue.toString(), etc. +``` + +For example, parsing the value `rgba(233, 45, 66, .5)` will return the following: + +```js +{ + nodes: [ + { + type: 'function', + value: 'rgba', + before: '', + after: '', + nodes: [ + { type: 'word', value: '233' }, + { type: 'div', value: ',', before: '', after: ' ' }, + { type: 'word', value: '45' }, + { type: 'div', value: ',', before: '', after: ' ' }, + { type: 'word', value: '66' }, + { type: 'div', value: ',', before: ' ', after: '' }, + { type: 'word', value: '.5' } + ] + } + ] +} +``` + +If you wanted to convert each `rgba()` value in `sourceCSS` to a hex value, you could do so like this: + +```js +var valueParser = require('postcss-value-parser'); + +var parsed = valueParser(sourceCSS); + +// walk() will visit all the of the nodes in the tree, +// invoking the callback for each. +parsed.walk(function (node) { + + // Since we only want to transform rgba() values, + // we can ignore anything else. + if (node.type !== 'function' && node.value !== 'rgba') return; + + // We can make an array of the rgba() arguments to feed to a + // convertToHex() function + var color = node.nodes.filter(function (node) { + return node.type === 'word'; + }).map(function (node) { + return Number(node.value); + }); // [233, 45, 66, .5] + + // Now we will transform the existing rgba() function node + // into a word node with the hex value + node.type = 'word'; + node.value = convertToHex(color); +}) + +parsed.toString(); // #E92D42 +``` + +## Nodes + +Each node is an object with these common properties: + +- **type**: The type of node (`word`, `string`, `div`, `space`, `comment`, or `function`). + Each type is documented below. +- **value**: Each node has a `value` property; but what exactly `value` means + is specific to the node type. Details are documented for each type below. +- **sourceIndex**: The starting index of the node within the original source + string. For example, given the source string `10px 20px`, the `word` node + whose value is `20px` will have a `sourceIndex` of `5`. + +### word + +The catch-all node type that includes keywords (e.g. `no-repeat`), +quantities (e.g. `20px`, `75%`, `1.5`), and hex colors (e.g. `#e6e6e6`). + +Node-specific properties: + +- **value**: The "word" itself. + +### string + +A quoted string value, e.g. `"something"` in `content: "something";`. + +Node-specific properties: + +- **value**: The text content of the string. +- **quote**: The quotation mark surrounding the string, either `"` or `'`. +- **unclosed**: `true` if the string was not closed properly. e.g. `"unclosed string `. + +### div + +A divider, for example + +- `,` in `animation-duration: 1s, 2s, 3s` +- `/` in `border-radius: 10px / 23px` +- `:` in `(min-width: 700px)` + +Node-specific properties: + +- **value**: The divider character. Either `,`, `/`, or `:` (see examples above). +- **before**: Whitespace before the divider. +- **after**: Whitespace after the divider. + +### space + +Whitespace used as a separator, e.g. ` ` occurring twice in `border: 1px solid black;`. + +Node-specific properties: + +- **value**: The whitespace itself. + +### comment + +A CSS comment starts with `/*` and ends with `*/` + +Node-specific properties: + +- **value**: The comment value without `/*` and `*/` +- **unclosed**: `true` if the comment was not closed properly. e.g. `/* comment without an end `. + +### function + +A CSS function, e.g. `rgb(0,0,0)` or `url(foo.bar)`. + +Function nodes have nodes nested within them: the function arguments. + +Additional properties: + +- **value**: The name of the function, e.g. `rgb` in `rgb(0,0,0)`. +- **before**: Whitespace after the opening parenthesis and before the first argument, + e.g. ` ` in `rgb( 0,0,0)`. +- **after**: Whitespace before the closing parenthesis and after the last argument, + e.g. ` ` in `rgb(0,0,0 )`. +- **nodes**: More nodes representing the arguments to the function. +- **unclosed**: `true` if the parentheses was not closed properly. e.g. `( unclosed-function `. + +Media features surrounded by parentheses are considered functions with an +empty value. For example, `(min-width: 700px)` parses to these nodes: + +```js +[ + { + type: 'function', value: '', before: '', after: '', + nodes: [ + { type: 'word', value: 'min-width' }, + { type: 'div', value: ':', before: '', after: ' ' }, + { type: 'word', value: '700px' } + ] + } +] +``` + +`url()` functions can be parsed a little bit differently depending on +whether the first character in the argument is a quotation mark. + +`url( /gfx/img/bg.jpg )` parses to: + +```js +{ type: 'function', sourceIndex: 0, value: 'url', before: ' ', after: ' ', nodes: [ + { type: 'word', sourceIndex: 5, value: '/gfx/img/bg.jpg' } +] } +``` + +`url( "/gfx/img/bg.jpg" )`, on the other hand, parses to: + +```js +{ type: 'function', sourceIndex: 0, value: 'url', before: ' ', after: ' ', nodes: [ + type: 'string', sourceIndex: 5, quote: '"', value: '/gfx/img/bg.jpg' }, +] } +``` + +### unicode-range + +The unicode-range CSS descriptor sets the specific range of characters to be +used from a font defined by @font-face and made available +for use on the current page (`unicode-range: U+0025-00FF`). + +Node-specific properties: + +- **value**: The "unicode-range" itself. + +## API + +``` +var valueParser = require('postcss-value-parser'); +``` + +### valueParser.unit(quantity) + +Parses `quantity`, distinguishing the number from the unit. Returns an object like the following: + +```js +// Given 2rem +{ + number: '2', + unit: 'rem' +} +``` + +If the `quantity` argument cannot be parsed as a number, returns `false`. + +*This function does not parse complete values*: you cannot pass it `1px solid black` and expect `px` as +the unit. Instead, you should pass it single quantities only. Parse `1px solid black`, then pass it +the stringified `1px` node (a `word` node) to parse the number and unit. + +### valueParser.stringify(nodes[, custom]) + +Stringifies a node or array of nodes. + +The `custom` function is called for each `node`; return a string to override the default behaviour. + +### valueParser.walk(nodes, callback[, bubble]) + +Walks each provided node, recursively walking all descendent nodes within functions. + +Returning `false` in the `callback` will prevent traversal of descendent nodes (within functions). +You can use this feature to for shallow iteration, walking over only the *immediate* children. +*Note: This only applies if `bubble` is `false` (which is the default).* + +By default, the tree is walked from the outermost node inwards. +To reverse the direction, pass `true` for the `bubble` argument. + +The `callback` is invoked with three arguments: `callback(node, index, nodes)`. + +- `node`: The current node. +- `index`: The index of the current node. +- `nodes`: The complete nodes array passed to `walk()`. + +Returns the `valueParser` instance. + +### var parsed = valueParser(value) + +Returns the parsed node tree. + +### parsed.nodes + +The array of nodes. + +### parsed.toString() + +Stringifies the node tree. + +### parsed.walk(callback[, bubble]) + +Walks each node inside `parsed.nodes`. See the documentation for `valueParser.walk()` above. + +# License + +MIT © [Bogdan Chadkin](mailto:trysound@yandex.ru) |