--- /dev/null
+"use strict";
+
+const atRuleParamIndex = require("../../utils/atRuleParamIndex");
+const declarationValueIndex = require("../../utils/declarationValueIndex");
+const getUnitFromValueNode = require("../../utils/getUnitFromValueNode");
+const optionsMatches = require("../../utils/optionsMatches");
+const report = require("../../utils/report");
+const ruleMessages = require("../../utils/ruleMessages");
+const validateOptions = require("../../utils/validateOptions");
+
+const _ = require("lodash");
+const valueParser = require("postcss-value-parser");
+
+const ruleName = "number-max-precision";
+
+const messages = ruleMessages(ruleName, {
+ expected: (number, precision) =>
+ `Expected "${number}" to be "${number.toFixed(precision)}"`
+});
+
+const rule = function(precision, options) {
+ return (root, result) => {
+ const validOptions = validateOptions(
+ result,
+ ruleName,
+ {
+ actual: precision,
+ possible: [_.isNumber]
+ },
+ {
+ optional: true,
+ actual: options,
+ possible: {
+ ignoreUnits: [_.isString]
+ }
+ }
+ );
+ if (!validOptions) {
+ return;
+ }
+
+ root.walkAtRules(atRule => {
+ if (atRule.name.toLowerCase() === "import") {
+ return;
+ }
+
+ check(atRule, atRule.params, atRuleParamIndex);
+ });
+
+ root.walkDecls(decl => check(decl, decl.value, declarationValueIndex));
+
+ function check(node, value, getIndex) {
+ // Get out quickly if there are no periods
+ if (value.indexOf(".") === -1) {
+ return;
+ }
+
+ valueParser(value).walk(valueNode => {
+ const unit = getUnitFromValueNode(valueNode);
+
+ if (optionsMatches(options, "ignoreUnits", unit)) {
+ return;
+ }
+
+ // Ignore `url` function
+ if (
+ valueNode.type === "function" &&
+ valueNode.value.toLowerCase() === "url"
+ ) {
+ return false;
+ }
+
+ // Ignore strings, comments, etc
+ if (valueNode.type !== "word") {
+ return;
+ }
+
+ const match = /\d*\.(\d+)/.exec(valueNode.value);
+
+ if (match === null) {
+ return;
+ }
+
+ if (match[1].length <= precision) {
+ return;
+ }
+
+ report({
+ result,
+ ruleName,
+ node,
+ index: getIndex(node) + valueNode.sourceIndex + match.index,
+ message: messages.expected(parseFloat(match[0]), precision)
+ });
+ });
+ }
+ };
+};
+
+rule.ruleName = ruleName;
+rule.messages = messages;
+module.exports = rule;