homebrewery/stylelint_plugins/align-colons.js

const stylelint = require('stylelint');

const { report, ruleMessages, validateOptions } = stylelint.utils;
const ruleName = 'naturalcrit/align-colons';
const messages = ruleMessages(ruleName, {
   expected: (rule) => `Expected colons aligned within rule "${rule}"`,
});


module.exports = stylelint.createPlugin(ruleName, function getPlugin(primaryOption, secondaryOptionObject, context) {
   return function lint(postcssRoot, postcssResult) {

       const validOptions = validateOptions(
           postcssResult,
           ruleName,
           {
                actual: primaryOption,
                possible: [
                true,
                false
                ]
           }
       );

       if (!validOptions) { //If the options are invalid, don't lint
           return;
       }
       const isAutoFixing = Boolean(context.fix);
       postcssRoot.walkRules(rule => { //Iterate CSS rules

            let maxColonPos = 0;
            let misaligned = false;
            rule.each(declaration => {

                if(declaration.type != "decl")
                    return;

                let colonPos = declaration.prop.length + declaration.raws.between.indexOf(":");
                if (maxColonPos > 0 && colonPos != maxColonPos) {
                    misaligned = true;
                }
                maxColonPos = Math.max(maxColonPos, colonPos);
            });

            if(misaligned) {
                if (isAutoFixing) { //We are in “fix” mode
                    rule.each(declaration => {
                        if(declaration.type != "decl")
                            return;

                        declaration.raws.between = " ".repeat(maxColonPos - declaration.prop.length) + ":" + declaration.raws.between.split(":")[1];
                    })
                } else { //We are in “report only” mode
                    report({
                        ruleName,
                        result: postcssResult,
                        message: messages.expected(rule.selector), // Build the reported message
                        node: rule, // Specify the reported node
                        word: rule.selector, // Which exact word caused the error? This positions the error properly
                    });
                }
                }
       });
   };
});

module.exports.ruleName = ruleName;
module.exports.messages = messages;