日本語禁止するESLintルール

no-japanese.js

/**
 * @fileoverview Rule to forbid writing Japanese
 * @author amagitakayosi
 */

"use strict";

var path = require('path');

//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------

module.exports = function (context) {
    return {
        "Program": function checkForForbiddenCharacters(node) {

            // 除外するファイルは無視する
            var excludePaths = context.options[0].excludePaths;
            for (var i = 0; i < excludePaths.length; i++) {
                var excludePathFull = path.resolve(__dirname, '..', excludePaths[i]) + '';
                if (context.getFilename().match(excludePathFull)) {
                    return;
                }
            }

            // 許容する文字を指定
            var allowedChars = context.options[0].allowedChars || '';
            var allowedCharsRegExp = new RegExp(
                '[' +allowedChars + ']+', 'g'
            );

            var errors = [];

            // asciiでない文字を含むトークンを記憶する
            var sourceCode = context.getSourceCode();
            var tokens = sourceCode.getTokens(node);
            tokens.forEach(function (token) {
                var value = token.value;

                var matches = value.match(/([^\x00-\x7F]+)/g);

                if (matches) {
                    value = value.replace(allowedCharsRegExp, '');
                }

                matches = value.match(/([^\x00-\x7F]+)/g);
                if (matches) {
                    errors.push({
                        line   : token.loc.start.line,
                        column : token.loc.start.column,
                        char   : matches[0],
                    });
                }
            });

            // エラーを出力
            errors.forEach(function (error) {
                context.report(node, {
                    line   : error.line,
                    column : error.column,
                }, 'Non-ascii character "' + error.char + '" found');
            });
        }
    };
};

module.exports.schema = [
    {
        "type": "object",
        "properties": {
            "allowedChars": {
                "type": "string",
            },
            "excludePaths": {
                "type": "array",
            },
        },
        "additionalProperties": false,
    },
];

Awesome! 💯 It works for all languages, not only Japanese 😄

JFYI: my fork with some changes