60 lines
2.2 KiB
JavaScript
60 lines
2.2 KiB
JavaScript
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import postcss from 'postcss';
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import valueParser from 'postcss-values-parser';
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var index = postcss.plugin('postcss-double-position-gradients', opts => {
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const preserve = 'preserve' in Object(opts) ? Boolean(opts.preserve) : true;
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return root => {
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// walk every declaration
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root.walkDecls(decl => {
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const originalValue = decl.value; // if the declaration value contains a gradient
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if (gradientFunctionRegExp.test(originalValue)) {
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const ast = valueParser(originalValue).parse(); // walk every function in the declaration value
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ast.walkFunctionNodes(fn => {
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// if the function is a gradient
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if (gradientFunctionNameRegExp.test(fn.value)) {
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const nodes = fn.nodes.slice(1, -1); // walk every argument to the function
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nodes.forEach((node, index) => {
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const node1back = Object(nodes[index - 1]);
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const node2back = Object(nodes[index - 2]);
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const isDoublePositionLength = node2back.type && node1back.type === 'number' && node.type === 'number'; // if the argument concludes a double-position gradient
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if (isDoublePositionLength) {
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// insert the fallback colors
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const color = node2back.clone();
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const comma = valueParser.comma({
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value: ',',
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raws: {
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after: ' '
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}
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});
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fn.insertBefore(node, comma);
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fn.insertBefore(node, color);
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}
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});
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}
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});
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const modifiedValue = ast.toString(); // if the value has changed due to double-position gradients
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if (originalValue !== modifiedValue) {
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// add the fallback value
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decl.cloneBefore({
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value: modifiedValue
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}); // conditionally remove the double-position gradient
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if (!preserve) {
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decl.remove();
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}
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}
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}
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});
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};
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});
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const gradientFunctionRegExp = /(repeating-)?(conic|linear|radial)-gradient\([\W\w]*\)/i;
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const gradientFunctionNameRegExp = /^(repeating-)?(conic|linear|radial)-gradient$/i;
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export default index;
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//# sourceMappingURL=index.es.mjs.map
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